package com.mm.android.deviceaddmodule.mobilecommon.widget.slidinguplayout;
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import android.content.Context;
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import android.support.v4.view.MotionEventCompat;
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import android.support.v4.view.VelocityTrackerCompat;
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import android.support.v4.view.ViewCompat;
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import android.support.v4.widget.ScrollerCompat;
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import android.view.MotionEvent;
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import android.view.VelocityTracker;
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import android.view.View;
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import android.view.ViewConfiguration;
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import android.view.ViewGroup;
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import android.view.animation.Interpolator;
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import java.util.Arrays;
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/**
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* ViewDragHelper is a utility class for writing custom ViewGroups. It offers a number
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* of useful operations and state tracking for allowing a user to drag and reposition
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* views within their parent ViewGroup.
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*/
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public class ViewDragHelper {
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private static final String TAG = "ViewDragHelper";
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/**
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* A null/invalid pointer ID.
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*/
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public static final int INVALID_POINTER = -1;
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/**
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* A view is not currently being dragged or animating as a result of a fling/snap.
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*/
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public static final int STATE_IDLE = 0;
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/**
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* A view is currently being dragged. The position is currently changing as a result
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* of user input or simulated user input.
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*/
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public static final int STATE_DRAGGING = 1;
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/**
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* A view is currently settling into place as a result of a fling or
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* predefined non-interactive motion.
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*/
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public static final int STATE_SETTLING = 2;
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/**
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* Edge flag indicating that the left edge should be affected.
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*/
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public static final int EDGE_LEFT = 1 << 0;
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/**
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* Edge flag indicating that the right edge should be affected.
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*/
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public static final int EDGE_RIGHT = 1 << 1;
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/**
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* Edge flag indicating that the top edge should be affected.
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*/
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public static final int EDGE_TOP = 1 << 2;
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/**
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* Edge flag indicating that the bottom edge should be affected.
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*/
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public static final int EDGE_BOTTOM = 1 << 3;
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/**
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* Edge flag set indicating all edges should be affected.
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*/
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public static final int EDGE_ALL = EDGE_LEFT | EDGE_TOP | EDGE_RIGHT | EDGE_BOTTOM;
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/**
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* Indicates that a check should occur along the horizontal axis
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*/
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public static final int DIRECTION_HORIZONTAL = 1 << 0;
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/**
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* Indicates that a check should occur along the vertical axis
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*/
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public static final int DIRECTION_VERTICAL = 1 << 1;
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/**
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* Indicates that a check should occur along all axes
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*/
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public static final int DIRECTION_ALL = DIRECTION_HORIZONTAL | DIRECTION_VERTICAL;
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private static final int EDGE_SIZE = 20; // dp
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private static final int BASE_SETTLE_DURATION = 256; // ms
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private static final int MAX_SETTLE_DURATION = 600; // ms
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// Current drag state; idle, dragging or settling
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private int mDragState;
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// Distance to travel before a drag may begin
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private int mTouchSlop;
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// Last known position/pointer tracking
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private int mActivePointerId = INVALID_POINTER;
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private float[] mInitialMotionX;
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private float[] mInitialMotionY;
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private float[] mLastMotionX;
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private float[] mLastMotionY;
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private int[] mInitialEdgesTouched;
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private int[] mEdgeDragsInProgress;
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private int[] mEdgeDragsLocked;
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private int mPointersDown;
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private VelocityTracker mVelocityTracker;
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private float mMaxVelocity;
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private float mMinVelocity;
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private int mEdgeSize;
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private int mTrackingEdges;
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private ScrollerCompat mScroller;
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private final Callback mCallback;
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private View mCapturedView;
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private boolean mReleaseInProgress;
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private final ViewGroup mParentView;
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/**
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* A Callback is used as a communication channel with the ViewDragHelper back to the
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* parent view using it. <code>on*</code>methods are invoked on siginficant events and several
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* accessor methods are expected to provide the ViewDragHelper with more information
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* about the state of the parent view upon request. The callback also makes decisions
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* governing the range and draggability of child views.
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*/
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public static abstract class Callback {
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/**
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* Called when the drag state changes. See the <code>STATE_*</code> constants
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* for more information.
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*
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* @param state The new drag state
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*
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* @see #STATE_IDLE
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* @see #STATE_DRAGGING
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* @see #STATE_SETTLING
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*/
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public void onViewDragStateChanged(int state) {}
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/**
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* Called when the captured view's position changes as the result of a drag or settle.
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*
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* @param changedView View whose position changed
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* @param left New X coordinate of the left edge of the view
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* @param top New Y coordinate of the top edge of the view
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* @param dx Change in X position from the last call
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* @param dy Change in Y position from the last call
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*/
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public void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) {}
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/**
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* Called when a child view is captured for dragging or settling. The ID of the pointer
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* currently dragging the captured view is supplied. If activePointerId is
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* identified as {@link #INVALID_POINTER} the capture is programmatic instead of
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* pointer-initiated.
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*
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* @param capturedChild Child view that was captured
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* @param activePointerId Pointer id tracking the child capture
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*/
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public void onViewCaptured(View capturedChild, int activePointerId) {}
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/**
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* Called when the child view is no longer being actively dragged.
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* The fling velocity is also supplied, if relevant. The velocity values may
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* be clamped to system minimums or maximums.
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*
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* <p>Calling code may decide to fling or otherwise release the view to let it
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* settle into place. It should do so using {@link #settleCapturedViewAt(int, int)}
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* or {@link #flingCapturedView(int, int, int, int)}. If the Callback invokes
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* one of these methods, the ViewDragHelper will enter {@link #STATE_SETTLING}
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* and the view capture will not fully end until it comes to a complete stop.
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* If neither of these methods is invoked before <code>onViewReleased</code> returns,
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* the view will stop in place and the ViewDragHelper will return to
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* {@link #STATE_IDLE}.</p>
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*
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* @param releasedChild The captured child view now being released
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* @param xvel X velocity of the pointer as it left the screen in pixels per second.
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* @param yvel Y velocity of the pointer as it left the screen in pixels per second.
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*/
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public void onViewReleased(View releasedChild, float xvel, float yvel) {}
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/**
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* Called when one of the subscribed edges in the parent view has been touched
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* by the user while no child view is currently captured.
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*
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* @param edgeFlags A combination of edge flags describing the edge(s) currently touched
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* @param pointerId ID of the pointer touching the described edge(s)
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* @see #EDGE_LEFT
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* @see #EDGE_TOP
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* @see #EDGE_RIGHT
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* @see #EDGE_BOTTOM
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*/
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public void onEdgeTouched(int edgeFlags, int pointerId) {}
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/**
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* Called when the given edge may become locked. This can happen if an edge drag
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* was preliminarily rejected before beginning, but after {@link #onEdgeTouched(int, int)}
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* was called. This method should return true to lock this edge or false to leave it
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* unlocked. The default behavior is to leave edges unlocked.
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*
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* @param edgeFlags A combination of edge flags describing the edge(s) locked
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* @return true to lock the edge, false to leave it unlocked
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*/
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public boolean onEdgeLock(int edgeFlags) {
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return false;
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}
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/**
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* Called when the user has started a deliberate drag away from one
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* of the subscribed edges in the parent view while no child view is currently captured.
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*
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* @param edgeFlags A combination of edge flags describing the edge(s) dragged
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* @param pointerId ID of the pointer touching the described edge(s)
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* @see #EDGE_LEFT
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* @see #EDGE_TOP
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* @see #EDGE_RIGHT
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* @see #EDGE_BOTTOM
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*/
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public void onEdgeDragStarted(int edgeFlags, int pointerId) {}
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/**
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* Called to determine the Z-order of child views.
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*
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* @param index the ordered position to query for
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* @return index of the view that should be ordered at position <code>index</code>
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*/
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public int getOrderedChildIndex(int index) {
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return index;
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}
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/**
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* Return the magnitude of a draggable child view's horizontal range of motion in pixels.
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* This method should return 0 for views that cannot move horizontally.
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*
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* @param child Child view to check
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* @return range of horizontal motion in pixels
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*/
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public int getViewHorizontalDragRange(View child) {
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return 0;
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}
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/**
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* Return the magnitude of a draggable child view's vertical range of motion in pixels.
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* This method should return 0 for views that cannot move vertically.
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*
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* @param child Child view to check
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* @return range of vertical motion in pixels
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*/
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public int getViewVerticalDragRange(View child) {
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return 0;
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}
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/**
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* Called when the user's input indicates that they want to capture the given child view
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* with the pointer indicated by pointerId. The callback should return true if the user
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* is permitted to drag the given view with the indicated pointer.
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*
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* <p>ViewDragHelper may call this method multiple times for the same view even if
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* the view is already captured; this indicates that a new pointer is trying to take
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* control of the view.</p>
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*
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* <p>If this method returns true, a call to {@link #onViewCaptured(View, int)}
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* will follow if the capture is successful.</p>
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*
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* @param child Child the user is attempting to capture
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* @param pointerId ID of the pointer attempting the capture
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* @return true if capture should be allowed, false otherwise
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*/
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public abstract boolean tryCaptureView(View child, int pointerId);
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/**
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* Restrict the motion of the dragged child view along the horizontal axis.
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* The default implementation does not allow horizontal motion; the extending
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* class must override this method and provide the desired clamping.
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*
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*
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* @param child Child view being dragged
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* @param left Attempted motion along the X axis
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* @param dx Proposed change in position for left
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* @return The new clamped position for left
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*/
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public int clampViewPositionHorizontal(View child, int left, int dx) {
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return 0;
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}
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/**
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* Restrict the motion of the dragged child view along the vertical axis.
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* The default implementation does not allow vertical motion; the extending
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* class must override this method and provide the desired clamping.
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*
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*
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* @param child Child view being dragged
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* @param top Attempted motion along the Y axis
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* @param dy Proposed change in position for top
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* @return The new clamped position for top
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*/
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public int clampViewPositionVertical(View child, int top, int dy) {
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return 0;
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}
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}
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/**
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* Interpolator defining the animation curve for mScroller
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*/
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private static final Interpolator sInterpolator = new Interpolator() {
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public float getInterpolation(float t) {
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t -= 1.0f;
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return t * t * t * t * t + 1.0f;
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}
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};
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private final Runnable mSetIdleRunnable = new Runnable() {
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public void run() {
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setDragState(STATE_IDLE);
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}
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};
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/**
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* Factory method to create a new ViewDragHelper.
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*
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* @param forParent Parent view to monitor
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* @param cb Callback to provide information and receive events
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* @return a new ViewDragHelper instance
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*/
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public static ViewDragHelper create(ViewGroup forParent, Callback cb) {
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return new ViewDragHelper(forParent.getContext(), forParent, null, cb);
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}
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/**
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* Factory method to create a new ViewDragHelper with the specified interpolator.
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*
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* @param forParent Parent view to monitor
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* @param interpolator interpolator for scroller
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* @param cb Callback to provide information and receive events
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* @return a new ViewDragHelper instance
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*/
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public static ViewDragHelper create(ViewGroup forParent, Interpolator interpolator, Callback cb) {
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return new ViewDragHelper(forParent.getContext(), forParent, interpolator, cb);
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}
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/**
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* Factory method to create a new ViewDragHelper.
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*
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* @param forParent Parent view to monitor
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* @param sensitivity Multiplier for how sensitive the helper should be about detecting
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* the start of a drag. Larger values are more sensitive. 1.0f is normal.
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* @param cb Callback to provide information and receive events
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* @return a new ViewDragHelper instance
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*/
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public static ViewDragHelper create(ViewGroup forParent, float sensitivity, Callback cb) {
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final ViewDragHelper helper = create(forParent, cb);
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helper.mTouchSlop = (int) (helper.mTouchSlop * (1 / sensitivity));
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return helper;
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}
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/**
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* Factory method to create a new ViewDragHelper with the specified interpolator.
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*
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* @param forParent Parent view to monitor
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* @param sensitivity Multiplier for how sensitive the helper should be about detecting
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* the start of a drag. Larger values are more sensitive. 1.0f is normal.
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* @param interpolator interpolator for scroller
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* @param cb Callback to provide information and receive events
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* @return a new ViewDragHelper instance
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*/
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public static ViewDragHelper create(ViewGroup forParent, float sensitivity, Interpolator interpolator, Callback cb) {
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final ViewDragHelper helper = create(forParent, interpolator, cb);
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helper.mTouchSlop = (int) (helper.mTouchSlop * (1 / sensitivity));
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return helper;
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}
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/**
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* Apps should use ViewDragHelper.create() to get a new instance.
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* This will allow VDH to use internal compatibility implementations for different
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* platform versions.
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* If the interpolator is null, the default interpolator will be used.
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*
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* @param context Context to initialize config-dependent params from
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* @param forParent Parent view to monitor
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* @param interpolator interpolator for scroller
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*/
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private ViewDragHelper(Context context, ViewGroup forParent, Interpolator interpolator, Callback cb) {
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if (forParent == null) {
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throw new IllegalArgumentException("Parent view may not be null");
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}
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if (cb == null) {
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throw new IllegalArgumentException("Callback may not be null");
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}
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mParentView = forParent;
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mCallback = cb;
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final ViewConfiguration vc = ViewConfiguration.get(context);
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final float density = context.getResources().getDisplayMetrics().density;
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mEdgeSize = (int) (EDGE_SIZE * density + 0.5f);
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mTouchSlop = vc.getScaledTouchSlop();
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mMaxVelocity = vc.getScaledMaximumFlingVelocity();
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mMinVelocity = vc.getScaledMinimumFlingVelocity();
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mScroller = ScrollerCompat.create(context, interpolator != null ? interpolator : sInterpolator);
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}
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/**
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* Set the minimum velocity that will be detected as having a magnitude greater than zero
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* in pixels per second. Callback methods accepting a velocity will be clamped appropriately.
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*
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* @param minVel Minimum velocity to detect
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*/
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public void setMinVelocity(float minVel) {
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mMinVelocity = minVel;
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}
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/**
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* Return the currently configured minimum velocity. Any flings with a magnitude less
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* than this value in pixels per second. Callback methods accepting a velocity will receive
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* zero as a velocity value if the real detected velocity was below this threshold.
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*
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* @return the minimum velocity that will be detected
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*/
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public float getMinVelocity() {
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return mMinVelocity;
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}
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/**
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* Retrieve the current drag state of this helper. This will return one of
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* {@link #STATE_IDLE}, {@link #STATE_DRAGGING} or {@link #STATE_SETTLING}.
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* @return The current drag state
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*/
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public int getViewDragState() {
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return mDragState;
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}
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/**
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* Enable edge tracking for the selected edges of the parent view.
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* The callback's {@link Callback#onEdgeTouched(int, int)} and
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* {@link Callback#onEdgeDragStarted(int, int)} methods will only be invoked
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* for edges for which edge tracking has been enabled.
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*
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* @param edgeFlags Combination of edge flags describing the edges to watch
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* @see #EDGE_LEFT
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* @see #EDGE_TOP
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* @see #EDGE_RIGHT
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* @see #EDGE_BOTTOM
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*/
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public void setEdgeTrackingEnabled(int edgeFlags) {
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mTrackingEdges = edgeFlags;
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}
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/**
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* Return the size of an edge. This is the range in pixels along the edges of this view
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* that will actively detect edge touches or drags if edge tracking is enabled.
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*
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* @return The size of an edge in pixels
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* @see #setEdgeTrackingEnabled(int)
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*/
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public int getEdgeSize() {
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return mEdgeSize;
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}
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/**
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* Capture a specific child view for dragging within the parent. The callback will be notified
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* but {@link Callback#tryCaptureView(View, int)} will not be asked permission to
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* capture this view.
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*
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* @param childView Child view to capture
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* @param activePointerId ID of the pointer that is dragging the captured child view
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*/
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public void captureChildView(View childView, int activePointerId) {
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if (childView.getParent() != mParentView) {
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throw new IllegalArgumentException("captureChildView: parameter must be a descendant " +
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"of the ViewDragHelper's tracked parent view (" + mParentView + ")");
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}
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mCapturedView = childView;
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mActivePointerId = activePointerId;
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mCallback.onViewCaptured(childView, activePointerId);
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setDragState(STATE_DRAGGING);
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}
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/**
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* @return The currently captured view, or null if no view has been captured.
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*/
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public View getCapturedView() {
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return mCapturedView;
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}
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/**
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* @return The ID of the pointer currently dragging the captured view,
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* or {@link #INVALID_POINTER}.
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*/
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public int getActivePointerId() {
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return mActivePointerId;
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}
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/**
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* @return The minimum distance in pixels that the user must travel to initiate a drag
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*/
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public int getTouchSlop() {
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return mTouchSlop;
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}
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/**
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* The result of a call to this method is equivalent to
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* {@link #processTouchEvent(MotionEvent)} receiving an ACTION_CANCEL event.
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*/
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public void cancel() {
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mActivePointerId = INVALID_POINTER;
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clearMotionHistory();
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if (mVelocityTracker != null) {
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mVelocityTracker.recycle();
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mVelocityTracker = null;
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}
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}
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/**
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* {@link #cancel()}, but also abort all motion in progress and snap to the end of any
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* animation.
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*/
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public void abort() {
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cancel();
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if (mDragState == STATE_SETTLING) {
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final int oldX = mScroller.getCurrX();
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final int oldY = mScroller.getCurrY();
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mScroller.abortAnimation();
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final int newX = mScroller.getCurrX();
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final int newY = mScroller.getCurrY();
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mCallback.onViewPositionChanged(mCapturedView, newX, newY, newX - oldX, newY - oldY);
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}
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setDragState(STATE_IDLE);
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}
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/**
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* Animate the view <code>child</code> to the given (left, top) position.
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* If this method returns true, the caller should invoke {@link #continueSettling(boolean)}
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* on each subsequent frame to continue the motion until it returns false. If this method
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* returns false there is no further work to do to complete the movement.
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*
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* <p>This operation does not count as a capture event, though {@link #getCapturedView()}
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* will still report the sliding view while the slide is in progress.</p>
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*
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* @param child Child view to capture and animate
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* @param finalLeft Final left position of child
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* @param finalTop Final top position of child
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* @return true if animation should continue through {@link #continueSettling(boolean)} calls
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*/
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public boolean smoothSlideViewTo(View child, int finalLeft, int finalTop) {
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mCapturedView = child;
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mActivePointerId = INVALID_POINTER;
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return forceSettleCapturedViewAt(finalLeft, finalTop, 0, 0);
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}
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/**
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* Settle the captured view at the given (left, top) position.
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* The appropriate velocity from prior motion will be taken into account.
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* If this method returns true, the caller should invoke {@link #continueSettling(boolean)}
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* on each subsequent frame to continue the motion until it returns false. If this method
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* returns false there is no further work to do to complete the movement.
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*
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* @param finalLeft Settled left edge position for the captured view
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* @param finalTop Settled top edge position for the captured view
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* @return true if animation should continue through {@link #continueSettling(boolean)} calls
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*/
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public boolean settleCapturedViewAt(int finalLeft, int finalTop) {
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if (!mReleaseInProgress) {
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throw new IllegalStateException("Cannot settleCapturedViewAt outside of a call to " +
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"Callback#onViewReleased");
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}
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return forceSettleCapturedViewAt(finalLeft, finalTop,
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(int) VelocityTrackerCompat.getXVelocity(mVelocityTracker, mActivePointerId),
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(int) VelocityTrackerCompat.getYVelocity(mVelocityTracker, mActivePointerId));
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}
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/**
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* Settle the captured view at the given (left, top) position.
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*
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* @param finalLeft Target left position for the captured view
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* @param finalTop Target top position for the captured view
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* @param xvel Horizontal velocity
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* @param yvel Vertical velocity
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* @return true if animation should continue through {@link #continueSettling(boolean)} calls
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*/
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private boolean forceSettleCapturedViewAt(int finalLeft, int finalTop, int xvel, int yvel) {
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final int startLeft = mCapturedView.getLeft();
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final int startTop = mCapturedView.getTop();
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final int dx = finalLeft - startLeft;
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final int dy = finalTop - startTop;
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if (dx == 0 && dy == 0) {
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// Nothing to do. Send callbacks, be done.
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mScroller.abortAnimation();
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setDragState(STATE_IDLE);
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return false;
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}
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final int duration = computeSettleDuration(mCapturedView, dx, dy, xvel, yvel);
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mScroller.startScroll(startLeft, startTop, dx, dy, duration);
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setDragState(STATE_SETTLING);
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return true;
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}
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private int computeSettleDuration(View child, int dx, int dy, int xvel, int yvel) {
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xvel = clampMag(xvel, (int) mMinVelocity, (int) mMaxVelocity);
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yvel = clampMag(yvel, (int) mMinVelocity, (int) mMaxVelocity);
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final int absDx = Math.abs(dx);
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final int absDy = Math.abs(dy);
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final int absXVel = Math.abs(xvel);
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final int absYVel = Math.abs(yvel);
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final int addedVel = absXVel + absYVel;
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final int addedDistance = absDx + absDy;
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final float xweight = xvel != 0 ? (float) absXVel / addedVel :
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(float) absDx / addedDistance;
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final float yweight = yvel != 0 ? (float) absYVel / addedVel :
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(float) absDy / addedDistance;
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int xduration = computeAxisDuration(dx, xvel, mCallback.getViewHorizontalDragRange(child));
|
int yduration = computeAxisDuration(dy, yvel, mCallback.getViewVerticalDragRange(child));
|
|
return (int) (xduration * xweight + yduration * yweight);
|
}
|
|
private int computeAxisDuration(int delta, int velocity, int motionRange) {
|
if (delta == 0) {
|
return 0;
|
}
|
|
final int width = mParentView.getWidth();
|
final int halfWidth = width / 2;
|
final float distanceRatio = Math.min(1f, (float) Math.abs(delta) / width);
|
final float distance = halfWidth + halfWidth *
|
distanceInfluenceForSnapDuration(distanceRatio);
|
|
int duration;
|
velocity = Math.abs(velocity);
|
if (velocity > 0) {
|
duration = 4 * Math.round(1000 * Math.abs(distance / velocity));
|
} else {
|
if(motionRange == 0){
|
return 0;
|
}
|
final float range = (float) Math.abs(delta) / motionRange;
|
duration = (int) ((range + 1) * BASE_SETTLE_DURATION);
|
}
|
return Math.min(duration, MAX_SETTLE_DURATION);
|
}
|
|
/**
|
* Clamp the magnitude of value for absMin and absMax.
|
* If the value is below the minimum, it will be clamped to zero.
|
* If the value is above the maximum, it will be clamped to the maximum.
|
*
|
* @param value Value to clamp
|
* @param absMin Absolute value of the minimum significant value to return
|
* @param absMax Absolute value of the maximum value to return
|
* @return The clamped value with the same sign as <code>value</code>
|
*/
|
private int clampMag(int value, int absMin, int absMax) {
|
final int absValue = Math.abs(value);
|
if (absValue < absMin) return 0;
|
if (absValue > absMax) return value > 0 ? absMax : -absMax;
|
return value;
|
}
|
|
/**
|
* Clamp the magnitude of value for absMin and absMax.
|
* If the value is below the minimum, it will be clamped to zero.
|
* If the value is above the maximum, it will be clamped to the maximum.
|
*
|
* @param value Value to clamp
|
* @param absMin Absolute value of the minimum significant value to return
|
* @param absMax Absolute value of the maximum value to return
|
* @return The clamped value with the same sign as <code>value</code>
|
*/
|
private float clampMag(float value, float absMin, float absMax) {
|
final float absValue = Math.abs(value);
|
if (absValue < absMin) return 0;
|
if (absValue > absMax) return value > 0 ? absMax : -absMax;
|
return value;
|
}
|
|
private float distanceInfluenceForSnapDuration(float f) {
|
f -= 0.5f; // center the values about 0.
|
f *= 0.3f * Math.PI / 2.0f;
|
return (float) Math.sin(f);
|
}
|
|
/**
|
* Settle the captured view based on standard free-moving fling behavior.
|
* The caller should invoke {@link #continueSettling(boolean)} on each subsequent frame
|
* to continue the motion until it returns false.
|
*
|
* @param minLeft Minimum X position for the view's left edge
|
* @param minTop Minimum Y position for the view's top edge
|
* @param maxLeft Maximum X position for the view's left edge
|
* @param maxTop Maximum Y position for the view's top edge
|
*/
|
public void flingCapturedView(int minLeft, int minTop, int maxLeft, int maxTop) {
|
if (!mReleaseInProgress) {
|
throw new IllegalStateException("Cannot flingCapturedView outside of a call to " +
|
"Callback#onViewReleased");
|
}
|
|
mScroller.fling(mCapturedView.getLeft(), mCapturedView.getTop(),
|
(int) VelocityTrackerCompat.getXVelocity(mVelocityTracker, mActivePointerId),
|
(int) VelocityTrackerCompat.getYVelocity(mVelocityTracker, mActivePointerId),
|
minLeft, maxLeft, minTop, maxTop);
|
|
setDragState(STATE_SETTLING);
|
}
|
|
/**
|
* Move the captured settling view by the appropriate amount for the current time.
|
* If <code>continueSettling</code> returns true, the caller should call it again
|
* on the next frame to continue.
|
*
|
* @param deferCallbacks true if state callbacks should be deferred via posted message.
|
* Set this to true if you are calling this method from
|
* {@link View#computeScroll()} or similar methods
|
* invoked as part of layout or drawing.
|
* @return true if settle is still in progress
|
*/
|
public boolean continueSettling(boolean deferCallbacks) {
|
// Make sure, there is a captured view
|
if (mCapturedView == null) {
|
return false;
|
}
|
if (mDragState == STATE_SETTLING) {
|
boolean keepGoing = mScroller.computeScrollOffset();
|
final int x = mScroller.getCurrX();
|
final int y = mScroller.getCurrY();
|
final int dx = x - mCapturedView.getLeft();
|
final int dy = y - mCapturedView.getTop();
|
|
if(!keepGoing && dy != 0) { //fix #525
|
//Invalid drag state
|
mCapturedView.setTop(0);
|
return true;
|
}
|
|
if (dx != 0) {
|
mCapturedView.offsetLeftAndRight(dx);
|
}
|
if (dy != 0) {
|
mCapturedView.offsetTopAndBottom(dy);
|
}
|
|
if (dx != 0 || dy != 0) {
|
mCallback.onViewPositionChanged(mCapturedView, x, y, dx, dy);
|
}
|
|
if (keepGoing && x == mScroller.getFinalX() && y == mScroller.getFinalY()) {
|
// Close enough. The interpolator/scroller might think we're still moving
|
// but the user sure doesn't.
|
mScroller.abortAnimation();
|
keepGoing = mScroller.isFinished();
|
}
|
|
if (!keepGoing) {
|
if (deferCallbacks) {
|
mParentView.post(mSetIdleRunnable);
|
} else {
|
setDragState(STATE_IDLE);
|
}
|
}
|
}
|
|
return mDragState == STATE_SETTLING;
|
}
|
|
/**
|
* Like all callback events this must happen on the UI thread, but release
|
* involves some extra semantics. During a release (mReleaseInProgress)
|
* is the only time it is valid to call {@link #settleCapturedViewAt(int, int)}
|
* or {@link #flingCapturedView(int, int, int, int)}.
|
*/
|
private void dispatchViewReleased(float xvel, float yvel) {
|
mReleaseInProgress = true;
|
mCallback.onViewReleased(mCapturedView, xvel, yvel);
|
mReleaseInProgress = false;
|
|
if (mDragState == STATE_DRAGGING) {
|
// onViewReleased didn't call a method that would have changed this. Go idle.
|
setDragState(STATE_IDLE);
|
}
|
}
|
|
private void clearMotionHistory() {
|
if (mInitialMotionX == null) {
|
return;
|
}
|
Arrays.fill(mInitialMotionX, 0);
|
Arrays.fill(mInitialMotionY, 0);
|
Arrays.fill(mLastMotionX, 0);
|
Arrays.fill(mLastMotionY, 0);
|
Arrays.fill(mInitialEdgesTouched, 0);
|
Arrays.fill(mEdgeDragsInProgress, 0);
|
Arrays.fill(mEdgeDragsLocked, 0);
|
mPointersDown = 0;
|
}
|
|
private void clearMotionHistory(int pointerId) {
|
if (mInitialMotionX == null || mInitialMotionX.length <= pointerId) {
|
return;
|
}
|
mInitialMotionX[pointerId] = 0;
|
mInitialMotionY[pointerId] = 0;
|
mLastMotionX[pointerId] = 0;
|
mLastMotionY[pointerId] = 0;
|
mInitialEdgesTouched[pointerId] = 0;
|
mEdgeDragsInProgress[pointerId] = 0;
|
mEdgeDragsLocked[pointerId] = 0;
|
mPointersDown &= ~(1 << pointerId);
|
}
|
|
private void ensureMotionHistorySizeForId(int pointerId) {
|
if (mInitialMotionX == null || mInitialMotionX.length <= pointerId) {
|
float[] imx = new float[pointerId + 1];
|
float[] imy = new float[pointerId + 1];
|
float[] lmx = new float[pointerId + 1];
|
float[] lmy = new float[pointerId + 1];
|
int[] iit = new int[pointerId + 1];
|
int[] edip = new int[pointerId + 1];
|
int[] edl = new int[pointerId + 1];
|
|
if (mInitialMotionX != null) {
|
System.arraycopy(mInitialMotionX, 0, imx, 0, mInitialMotionX.length);
|
System.arraycopy(mInitialMotionY, 0, imy, 0, mInitialMotionY.length);
|
System.arraycopy(mLastMotionX, 0, lmx, 0, mLastMotionX.length);
|
System.arraycopy(mLastMotionY, 0, lmy, 0, mLastMotionY.length);
|
System.arraycopy(mInitialEdgesTouched, 0, iit, 0, mInitialEdgesTouched.length);
|
System.arraycopy(mEdgeDragsInProgress, 0, edip, 0, mEdgeDragsInProgress.length);
|
System.arraycopy(mEdgeDragsLocked, 0, edl, 0, mEdgeDragsLocked.length);
|
}
|
|
mInitialMotionX = imx;
|
mInitialMotionY = imy;
|
mLastMotionX = lmx;
|
mLastMotionY = lmy;
|
mInitialEdgesTouched = iit;
|
mEdgeDragsInProgress = edip;
|
mEdgeDragsLocked = edl;
|
}
|
}
|
|
private void saveInitialMotion(float x, float y, int pointerId) {
|
ensureMotionHistorySizeForId(pointerId);
|
mInitialMotionX[pointerId] = mLastMotionX[pointerId] = x;
|
mInitialMotionY[pointerId] = mLastMotionY[pointerId] = y;
|
mInitialEdgesTouched[pointerId] = getEdgesTouched((int) x, (int) y);
|
mPointersDown |= 1 << pointerId;
|
}
|
|
private void saveLastMotion(MotionEvent ev) {
|
final int pointerCount = MotionEventCompat.getPointerCount(ev);
|
for (int i = 0; i < pointerCount; i++) {
|
final int pointerId = MotionEventCompat.getPointerId(ev, i);
|
final float x = MotionEventCompat.getX(ev, i);
|
final float y = MotionEventCompat.getY(ev, i);
|
// Sometimes we can try and save last motion for a pointer never recorded in initial motion. In this case we just discard it.
|
if (mLastMotionX != null && mLastMotionY != null
|
&& mLastMotionX.length > pointerId && mLastMotionY.length > pointerId) {
|
mLastMotionX[pointerId] = x;
|
mLastMotionY[pointerId] = y;
|
}
|
}
|
}
|
|
/**
|
* Check if the given pointer ID represents a pointer that is currently down (to the best
|
* of the ViewDragHelper's knowledge).
|
*
|
* <p>The state used to report this information is populated by the methods
|
* {@link #shouldInterceptTouchEvent(MotionEvent)} or
|
* {@link #processTouchEvent(MotionEvent)}. If one of these methods has not
|
* been called for all relevant MotionEvents to track, the information reported
|
* by this method may be stale or incorrect.</p>
|
*
|
* @param pointerId pointer ID to check; corresponds to IDs provided by MotionEvent
|
* @return true if the pointer with the given ID is still down
|
*/
|
public boolean isPointerDown(int pointerId) {
|
return (mPointersDown & 1 << pointerId) != 0;
|
}
|
|
void setDragState(int state) {
|
if (mDragState != state) {
|
mDragState = state;
|
mCallback.onViewDragStateChanged(state);
|
if (mDragState == STATE_IDLE) {
|
mCapturedView = null;
|
}
|
}
|
}
|
|
/**
|
* Attempt to capture the view with the given pointer ID. The callback will be involved.
|
* This will put us into the "dragging" state. If we've already captured this view with
|
* this pointer this method will immediately return true without consulting the callback.
|
*
|
* @param toCapture View to capture
|
* @param pointerId Pointer to capture with
|
* @return true if capture was successful
|
*/
|
boolean tryCaptureViewForDrag(View toCapture, int pointerId) {
|
if (toCapture == mCapturedView && mActivePointerId == pointerId) {
|
// Already done!
|
return true;
|
}
|
if (toCapture != null && mCallback.tryCaptureView(toCapture, pointerId)) {
|
mActivePointerId = pointerId;
|
captureChildView(toCapture, pointerId);
|
return true;
|
}
|
return false;
|
}
|
|
/**
|
* Tests scrollability within child views of v given a delta of dx.
|
*
|
* @param v View to test for horizontal scrollability
|
* @param checkV Whether the view v passed should itself be checked for scrollability (true),
|
* or just its children (false).
|
* @param dx Delta scrolled in pixels along the X axis
|
* @param dy Delta scrolled in pixels along the Y axis
|
* @param x X coordinate of the active touch point
|
* @param y Y coordinate of the active touch point
|
* @return true if child views of v can be scrolled by delta of dx.
|
*/
|
protected boolean canScroll(View v, boolean checkV, int dx, int dy, int x, int y) {
|
if (v instanceof ViewGroup) {
|
final ViewGroup group = (ViewGroup) v;
|
final int scrollX = v.getScrollX();
|
final int scrollY = v.getScrollY();
|
final int count = group.getChildCount();
|
// Count backwards - let topmost views consume scroll distance first.
|
for (int i = count - 1; i >= 0; i--) {
|
// TODO: Add versioned support here for transformed views.
|
// This will not work for transformed views in Honeycomb+
|
final View child = group.getChildAt(i);
|
if (x + scrollX >= child.getLeft() && x + scrollX < child.getRight() &&
|
y + scrollY >= child.getTop() && y + scrollY < child.getBottom() &&
|
canScroll(child, true, dx, dy, x + scrollX - child.getLeft(),
|
y + scrollY - child.getTop())) {
|
return true;
|
}
|
}
|
}
|
|
return checkV && (ViewCompat.canScrollHorizontally(v, -dx) ||
|
ViewCompat.canScrollVertically(v, -dy));
|
}
|
|
/**
|
* Check if this event as provided to the parent view's onInterceptTouchEvent should
|
* cause the parent to intercept the touch event stream.
|
*
|
* @param ev MotionEvent provided to onInterceptTouchEvent
|
* @return true if the parent view should return true from onInterceptTouchEvent
|
*/
|
public boolean shouldInterceptTouchEvent(MotionEvent ev) {
|
final int action = MotionEventCompat.getActionMasked(ev);
|
final int actionIndex = MotionEventCompat.getActionIndex(ev);
|
|
if (action == MotionEvent.ACTION_DOWN) {
|
// Reset things for a new event stream, just in case we didn't get
|
// the whole previous stream.
|
cancel();
|
}
|
|
if (mVelocityTracker == null) {
|
mVelocityTracker = VelocityTracker.obtain();
|
}
|
mVelocityTracker.addMovement(ev);
|
|
switch (action) {
|
case MotionEvent.ACTION_DOWN: {
|
final float x = ev.getX();
|
final float y = ev.getY();
|
final int pointerId = MotionEventCompat.getPointerId(ev, 0);
|
saveInitialMotion(x, y, pointerId);
|
|
final View toCapture = findTopChildUnder((int) x, (int) y);
|
|
// Catch a settling view if possible.
|
if (toCapture == mCapturedView && mDragState == STATE_SETTLING) {
|
tryCaptureViewForDrag(toCapture, pointerId);
|
}
|
|
final int edgesTouched = mInitialEdgesTouched[pointerId];
|
if ((edgesTouched & mTrackingEdges) != 0) {
|
mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
|
}
|
break;
|
}
|
|
case MotionEventCompat.ACTION_POINTER_DOWN: {
|
final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
|
final float x = MotionEventCompat.getX(ev, actionIndex);
|
final float y = MotionEventCompat.getY(ev, actionIndex);
|
|
saveInitialMotion(x, y, pointerId);
|
|
// A ViewDragHelper can only manipulate one view at a time.
|
if (mDragState == STATE_IDLE) {
|
final int edgesTouched = mInitialEdgesTouched[pointerId];
|
if ((edgesTouched & mTrackingEdges) != 0) {
|
mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
|
}
|
} else if (mDragState == STATE_SETTLING) {
|
// Catch a settling view if possible.
|
final View toCapture = findTopChildUnder((int) x, (int) y);
|
if (toCapture == mCapturedView) {
|
tryCaptureViewForDrag(toCapture, pointerId);
|
}
|
}
|
break;
|
}
|
|
case MotionEvent.ACTION_MOVE: {
|
// First to cross a touch slop over a draggable view wins. Also report edge drags.
|
final int pointerCount = MotionEventCompat.getPointerCount(ev);
|
for (int i = 0; i < pointerCount && mInitialMotionX != null && mInitialMotionY != null; i++) {
|
final int pointerId = MotionEventCompat.getPointerId(ev, i);
|
if (pointerId >= mInitialMotionX.length || pointerId >= mInitialMotionY.length) {
|
continue;
|
}
|
final float x = MotionEventCompat.getX(ev, i);
|
final float y = MotionEventCompat.getY(ev, i);
|
final float dx = x - mInitialMotionX[pointerId];
|
final float dy = y - mInitialMotionY[pointerId];
|
|
reportNewEdgeDrags(dx, dy, pointerId);
|
if (mDragState == STATE_DRAGGING) {
|
// Callback might have started an edge drag
|
break;
|
}
|
|
final View toCapture = findTopChildUnder((int)mInitialMotionX[pointerId], (int)mInitialMotionY[pointerId]);
|
if (toCapture != null && checkTouchSlop(toCapture, dx, dy) &&
|
tryCaptureViewForDrag(toCapture, pointerId)) {
|
break;
|
}
|
}
|
saveLastMotion(ev);
|
break;
|
}
|
|
case MotionEventCompat.ACTION_POINTER_UP: {
|
final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
|
clearMotionHistory(pointerId);
|
break;
|
}
|
|
case MotionEvent.ACTION_UP:
|
case MotionEvent.ACTION_CANCEL: {
|
cancel();
|
break;
|
}
|
}
|
|
return mDragState == STATE_DRAGGING;
|
}
|
|
/**
|
* Process a touch event received by the parent view. This method will dispatch callback events
|
* as needed before returning. The parent view's onTouchEvent implementation should call this.
|
*
|
* @param ev The touch event received by the parent view
|
*/
|
public void processTouchEvent(MotionEvent ev) {
|
final int action = MotionEventCompat.getActionMasked(ev);
|
final int actionIndex = MotionEventCompat.getActionIndex(ev);
|
|
if (action == MotionEvent.ACTION_DOWN) {
|
// Reset things for a new event stream, just in case we didn't get
|
// the whole previous stream.
|
cancel();
|
}
|
|
if (mVelocityTracker == null) {
|
mVelocityTracker = VelocityTracker.obtain();
|
}
|
mVelocityTracker.addMovement(ev);
|
|
switch (action) {
|
case MotionEvent.ACTION_DOWN: {
|
final float x = ev.getX();
|
final float y = ev.getY();
|
final int pointerId = MotionEventCompat.getPointerId(ev, 0);
|
final View toCapture = findTopChildUnder((int) x, (int) y);
|
|
saveInitialMotion(x, y, pointerId);
|
|
// Since the parent is already directly processing this touch event,
|
// there is no reason to delay for a slop before dragging.
|
// Start immediately if possible.
|
tryCaptureViewForDrag(toCapture, pointerId);
|
|
final int edgesTouched = mInitialEdgesTouched[pointerId];
|
if ((edgesTouched & mTrackingEdges) != 0) {
|
mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
|
}
|
break;
|
}
|
|
case MotionEventCompat.ACTION_POINTER_DOWN: {
|
final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
|
final float x = MotionEventCompat.getX(ev, actionIndex);
|
final float y = MotionEventCompat.getY(ev, actionIndex);
|
|
saveInitialMotion(x, y, pointerId);
|
|
// A ViewDragHelper can only manipulate one view at a time.
|
if (mDragState == STATE_IDLE) {
|
// If we're idle we can do anything! Treat it like a normal down event.
|
|
final View toCapture = findTopChildUnder((int) x, (int) y);
|
tryCaptureViewForDrag(toCapture, pointerId);
|
|
final int edgesTouched = mInitialEdgesTouched[pointerId];
|
if ((edgesTouched & mTrackingEdges) != 0) {
|
mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
|
}
|
} else if (isCapturedViewUnder((int) x, (int) y)) {
|
// We're still tracking a captured view. If the same view is under this
|
// point, we'll swap to controlling it with this pointer instead.
|
// (This will still work if we're "catching" a settling view.)
|
|
tryCaptureViewForDrag(mCapturedView, pointerId);
|
}
|
break;
|
}
|
|
case MotionEvent.ACTION_MOVE: {
|
if (mDragState == STATE_DRAGGING) {
|
final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
|
final float x = MotionEventCompat.getX(ev, index);
|
final float y = MotionEventCompat.getY(ev, index);
|
final int idx = (int) (x - mLastMotionX[mActivePointerId]);
|
final int idy = (int) (y - mLastMotionY[mActivePointerId]);
|
|
dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);
|
|
saveLastMotion(ev);
|
} else {
|
// Check to see if any pointer is now over a draggable view.
|
final int pointerCount = MotionEventCompat.getPointerCount(ev);
|
for (int i = 0; i < pointerCount; i++) {
|
final int pointerId = MotionEventCompat.getPointerId(ev, i)
|
;
|
final float x = MotionEventCompat.getX(ev, i);
|
final float y = MotionEventCompat.getY(ev, i);
|
final float dx = x - mInitialMotionX[pointerId];
|
final float dy = y - mInitialMotionY[pointerId];
|
|
reportNewEdgeDrags(dx, dy, pointerId);
|
if (mDragState == STATE_DRAGGING) {
|
// Callback might have started an edge drag.
|
break;
|
}
|
|
final View toCapture = findTopChildUnder((int) mInitialMotionX[pointerId], (int) mInitialMotionY[pointerId]);
|
if (checkTouchSlop(toCapture, dx, dy) &&
|
tryCaptureViewForDrag(toCapture, pointerId)) {
|
break;
|
}
|
}
|
saveLastMotion(ev);
|
}
|
break;
|
}
|
|
case MotionEventCompat.ACTION_POINTER_UP: {
|
final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
|
if (mDragState == STATE_DRAGGING && pointerId == mActivePointerId) {
|
// Try to find another pointer that's still holding on to the captured view.
|
int newActivePointer = INVALID_POINTER;
|
final int pointerCount = MotionEventCompat.getPointerCount(ev);
|
for (int i = 0; i < pointerCount; i++) {
|
final int id = MotionEventCompat.getPointerId(ev, i);
|
if (id == mActivePointerId) {
|
// This one's going away, skip.
|
continue;
|
}
|
|
final float x = MotionEventCompat.getX(ev, i);
|
final float y = MotionEventCompat.getY(ev, i);
|
if (findTopChildUnder((int) x, (int) y) == mCapturedView &&
|
tryCaptureViewForDrag(mCapturedView, id)) {
|
newActivePointer = mActivePointerId;
|
break;
|
}
|
}
|
|
if (newActivePointer == INVALID_POINTER) {
|
// We didn't find another pointer still touching the view, release it.
|
releaseViewForPointerUp();
|
}
|
}
|
clearMotionHistory(pointerId);
|
break;
|
}
|
|
case MotionEvent.ACTION_UP: {
|
if (mDragState == STATE_DRAGGING) {
|
releaseViewForPointerUp();
|
}
|
cancel();
|
break;
|
}
|
|
case MotionEvent.ACTION_CANCEL: {
|
if (mDragState == STATE_DRAGGING) {
|
dispatchViewReleased(0, 0);
|
}
|
cancel();
|
break;
|
}
|
}
|
}
|
|
private void reportNewEdgeDrags(float dx, float dy, int pointerId) {
|
int dragsStarted = 0;
|
if (checkNewEdgeDrag(dx, dy, pointerId, EDGE_LEFT)) {
|
dragsStarted |= EDGE_LEFT;
|
}
|
if (checkNewEdgeDrag(dy, dx, pointerId, EDGE_TOP)) {
|
dragsStarted |= EDGE_TOP;
|
}
|
if (checkNewEdgeDrag(dx, dy, pointerId, EDGE_RIGHT)) {
|
dragsStarted |= EDGE_RIGHT;
|
}
|
if (checkNewEdgeDrag(dy, dx, pointerId, EDGE_BOTTOM)) {
|
dragsStarted |= EDGE_BOTTOM;
|
}
|
|
if (dragsStarted != 0) {
|
mEdgeDragsInProgress[pointerId] |= dragsStarted;
|
mCallback.onEdgeDragStarted(dragsStarted, pointerId);
|
}
|
}
|
|
private boolean checkNewEdgeDrag(float delta, float odelta, int pointerId, int edge) {
|
final float absDelta = Math.abs(delta);
|
final float absODelta = Math.abs(odelta);
|
|
if ((mInitialEdgesTouched[pointerId] & edge) != edge || (mTrackingEdges & edge) == 0 ||
|
(mEdgeDragsLocked[pointerId] & edge) == edge ||
|
(mEdgeDragsInProgress[pointerId] & edge) == edge ||
|
(absDelta <= mTouchSlop && absODelta <= mTouchSlop)) {
|
return false;
|
}
|
if (absDelta < absODelta * 0.5f && mCallback.onEdgeLock(edge)) {
|
mEdgeDragsLocked[pointerId] |= edge;
|
return false;
|
}
|
return (mEdgeDragsInProgress[pointerId] & edge) == 0 && absDelta > mTouchSlop;
|
}
|
|
/**
|
* Check if we've crossed a reasonable touch slop for the given child view.
|
* If the child cannot be dragged along the horizontal or vertical axis, motion
|
* along that axis will not count toward the slop check.
|
*
|
* @param child Child to check
|
* @param dx Motion since initial position along X axis
|
* @param dy Motion since initial position along Y axis
|
* @return true if the touch slop has been crossed
|
*/
|
private boolean checkTouchSlop(View child, float dx, float dy) {
|
if (child == null) {
|
return false;
|
}
|
final boolean checkHorizontal = mCallback.getViewHorizontalDragRange(child) > 0;
|
final boolean checkVertical = mCallback.getViewVerticalDragRange(child) > 0;
|
|
if (checkHorizontal && checkVertical) {
|
return dx * dx + dy * dy > mTouchSlop * mTouchSlop;
|
} else if (checkHorizontal) {
|
return Math.abs(dx) > mTouchSlop;
|
} else if (checkVertical) {
|
return Math.abs(dy) > mTouchSlop;
|
}
|
return false;
|
}
|
|
/**
|
* Check if any pointer tracked in the current gesture has crossed
|
* the required slop threshold.
|
*
|
* <p>This depends on internal state populated by
|
* {@link #shouldInterceptTouchEvent(MotionEvent)} or
|
* {@link #processTouchEvent(MotionEvent)}. You should only rely on
|
* the results of this method after all currently available touch data
|
* has been provided to one of these two methods.</p>
|
*
|
* @param directions Combination of direction flags, see {@link #DIRECTION_HORIZONTAL},
|
* {@link #DIRECTION_VERTICAL}, {@link #DIRECTION_ALL}
|
* @return true if the slop threshold has been crossed, false otherwise
|
*/
|
public boolean checkTouchSlop(int directions) {
|
final int count = mInitialMotionX.length;
|
for (int i = 0; i < count; i++) {
|
if (checkTouchSlop(directions, i)) {
|
return true;
|
}
|
}
|
return false;
|
}
|
|
/**
|
* Check if the specified pointer tracked in the current gesture has crossed
|
* the required slop threshold.
|
*
|
* <p>This depends on internal state populated by
|
* {@link #shouldInterceptTouchEvent(MotionEvent)} or
|
* {@link #processTouchEvent(MotionEvent)}. You should only rely on
|
* the results of this method after all currently available touch data
|
* has been provided to one of these two methods.</p>
|
*
|
* @param directions Combination of direction flags, see {@link #DIRECTION_HORIZONTAL},
|
* {@link #DIRECTION_VERTICAL}, {@link #DIRECTION_ALL}
|
* @param pointerId ID of the pointer to slop check as specified by MotionEvent
|
* @return true if the slop threshold has been crossed, false otherwise
|
*/
|
public boolean checkTouchSlop(int directions, int pointerId) {
|
if (!isPointerDown(pointerId)) {
|
return false;
|
}
|
|
final boolean checkHorizontal = (directions & DIRECTION_HORIZONTAL) == DIRECTION_HORIZONTAL;
|
final boolean checkVertical = (directions & DIRECTION_VERTICAL) == DIRECTION_VERTICAL;
|
|
final float dx = mLastMotionX[pointerId] - mInitialMotionX[pointerId];
|
final float dy = mLastMotionY[pointerId] - mInitialMotionY[pointerId];
|
|
if (checkHorizontal && checkVertical) {
|
return dx * dx + dy * dy > mTouchSlop * mTouchSlop;
|
} else if (checkHorizontal) {
|
return Math.abs(dx) > mTouchSlop;
|
} else if (checkVertical) {
|
return Math.abs(dy) > mTouchSlop;
|
}
|
return false;
|
}
|
|
/**
|
* Check if any of the edges specified were initially touched in the currently active gesture.
|
* If there is no currently active gesture this method will return false.
|
*
|
* @param edges Edges to check for an initial edge touch. See {@link #EDGE_LEFT},
|
* {@link #EDGE_TOP}, {@link #EDGE_RIGHT}, {@link #EDGE_BOTTOM} and
|
* {@link #EDGE_ALL}
|
* @return true if any of the edges specified were initially touched in the current gesture
|
*/
|
public boolean isEdgeTouched(int edges) {
|
final int count = mInitialEdgesTouched.length;
|
for (int i = 0; i < count; i++) {
|
if (isEdgeTouched(edges, i)) {
|
return true;
|
}
|
}
|
return false;
|
}
|
|
/**
|
* Check if any of the edges specified were initially touched by the pointer with
|
* the specified ID. If there is no currently active gesture or if there is no pointer with
|
* the given ID currently down this method will return false.
|
*
|
* @param edges Edges to check for an initial edge touch. See {@link #EDGE_LEFT},
|
* {@link #EDGE_TOP}, {@link #EDGE_RIGHT}, {@link #EDGE_BOTTOM} and
|
* {@link #EDGE_ALL}
|
* @return true if any of the edges specified were initially touched in the current gesture
|
*/
|
public boolean isEdgeTouched(int edges, int pointerId) {
|
return isPointerDown(pointerId) && (mInitialEdgesTouched[pointerId] & edges) != 0;
|
}
|
|
public boolean isDragging() {
|
return mDragState == STATE_DRAGGING;
|
}
|
|
private void releaseViewForPointerUp() {
|
mVelocityTracker.computeCurrentVelocity(1000, mMaxVelocity);
|
final float xvel = clampMag(
|
VelocityTrackerCompat.getXVelocity(mVelocityTracker, mActivePointerId),
|
mMinVelocity, mMaxVelocity);
|
final float yvel = clampMag(
|
VelocityTrackerCompat.getYVelocity(mVelocityTracker, mActivePointerId),
|
mMinVelocity, mMaxVelocity);
|
dispatchViewReleased(xvel, yvel);
|
}
|
|
private void dragTo(int left, int top, int dx, int dy) {
|
int clampedX = left;
|
int clampedY = top;
|
final int oldLeft = mCapturedView.getLeft();
|
final int oldTop = mCapturedView.getTop();
|
if (dx != 0) {
|
clampedX = mCallback.clampViewPositionHorizontal(mCapturedView, left, dx);
|
mCapturedView.offsetLeftAndRight(clampedX - oldLeft);
|
}
|
if (dy != 0) {
|
clampedY = mCallback.clampViewPositionVertical(mCapturedView, top, dy);
|
mCapturedView.offsetTopAndBottom(clampedY - oldTop);
|
}
|
|
if (dx != 0 || dy != 0) {
|
final int clampedDx = clampedX - oldLeft;
|
final int clampedDy = clampedY - oldTop;
|
mCallback.onViewPositionChanged(mCapturedView, clampedX, clampedY,
|
clampedDx, clampedDy);
|
}
|
}
|
|
/**
|
* Determine if the currently captured view is under the given point in the
|
* parent view's coordinate system. If there is no captured view this method
|
* will return false.
|
*
|
* @param x X position to test in the parent's coordinate system
|
* @param y Y position to test in the parent's coordinate system
|
* @return true if the captured view is under the given point, false otherwise
|
*/
|
public boolean isCapturedViewUnder(int x, int y) {
|
return isViewUnder(mCapturedView, x, y);
|
}
|
|
/**
|
* Determine if the supplied view is under the given point in the
|
* parent view's coordinate system.
|
*
|
* @param view Child view of the parent to hit test
|
* @param x X position to test in the parent's coordinate system
|
* @param y Y position to test in the parent's coordinate system
|
* @return true if the supplied view is under the given point, false otherwise
|
*/
|
public boolean isViewUnder(View view, int x, int y) {
|
if (view == null) {
|
return false;
|
}
|
return x >= view.getLeft() &&
|
x < view.getRight() &&
|
y >= view.getTop() &&
|
y < view.getBottom();
|
}
|
|
/**
|
* Find the topmost child under the given point within the parent view's coordinate system.
|
* The child order is determined using {@link Callback#getOrderedChildIndex(int)}.
|
*
|
* @param x X position to test in the parent's coordinate system
|
* @param y Y position to test in the parent's coordinate system
|
* @return The topmost child view under (x, y) or null if none found.
|
*/
|
public View findTopChildUnder(int x, int y) {
|
final int childCount = mParentView.getChildCount();
|
for (int i = childCount - 1; i >= 0; i--) {
|
final View child = mParentView.getChildAt(mCallback.getOrderedChildIndex(i));
|
if (x >= child.getLeft() && x < child.getRight() &&
|
y >= child.getTop() && y < child.getBottom()) {
|
return child;
|
}
|
}
|
return null;
|
}
|
|
private int getEdgesTouched(int x, int y) {
|
int result = 0;
|
|
if (x < mParentView.getLeft() + mEdgeSize) result |= EDGE_LEFT;
|
if (y < mParentView.getTop() + mEdgeSize) result |= EDGE_TOP;
|
if (x > mParentView.getRight() - mEdgeSize) result |= EDGE_RIGHT;
|
if (y > mParentView.getBottom() - mEdgeSize) result |= EDGE_BOTTOM;
|
|
return result;
|
}
|
}
|
