wxr
2022-11-23 1e7b3abd15d37f6c6bc97ac14922457b9604c275
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package com.mm.android.deviceaddmodule.mobilecommon.widget.sticky.stickylistheaders;
 
import android.content.Context;
import android.database.DataSetObserver;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ListAdapter;
import android.widget.ListView;
 
import java.util.ArrayList;
 
public class StickyListHeadersListView extends ListView implements
        OnScrollListener {
 
    public interface OnHeaderClickListener {
        public void onHeaderClick(StickyListHeadersListView l, View header,
                                  int itemPosition, long headerId, boolean currentlySticky);
    }
    
    private OnScrollListener scrollListener;
    private boolean areHeadersSticky = true;
    private int headerBottomPosition;
    private View header;
    private int dividerHeight;
    private Drawable divider;
    private boolean clippingToPadding;
    private boolean clipToPaddingHasBeenSet;
    private final Rect clippingRect = new Rect();
    private Long currentHeaderId = null;
    private StickyListHeadersAdapterWrapper adapter;
    private float headerDownY = -1;
    private boolean headerBeingPressed = false;
    private OnHeaderClickListener onHeaderClickListener;
    private int headerPosition;
    private ViewConfiguration viewConfig;
    private ArrayList<View> footerViews;
 
    private StickyListHeadersAdapterWrapper.OnHeaderClickListener addapterHeaderClickListener = new StickyListHeadersAdapterWrapper.OnHeaderClickListener() {
 
        @Override
        public void onHeaderClick(View header, int itemPosition, long headerId) {
            if (onHeaderClickListener != null) {
                onHeaderClickListener.onHeaderClick(
                        StickyListHeadersListView.this, header, itemPosition,
                        headerId, false);
            }
        }
    };
 
    private DataSetObserver dataSetChangedObserver = new DataSetObserver() {
        @Override
        public void onChanged() {
            reset();
        }
 
        @Override
        public void onInvalidated() {
            reset();
        }
    };
 
    public StickyListHeadersListView(Context context) {
        this(context, null);
    }
 
    public StickyListHeadersListView(Context context, AttributeSet attrs) {
        this(context, attrs, android.R.attr.listViewStyle);
    }
 
    public StickyListHeadersListView(Context context, AttributeSet attrs,
            int defStyle) {
        super(context, attrs, defStyle);
 
        super.setOnScrollListener(this);
        // null out divider, dividers are handled by adapter so they look good
        // with headers
        super.setDivider(null);
        super.setDividerHeight(0);
        setVerticalFadingEdgeEnabled(false);
        viewConfig = ViewConfiguration.get(context);
    }
    
    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        super.onLayout(changed, l, t, r, b);
        if(changed){
            reset();
        }
    }
 
    private void reset() {
        headerBottomPosition = 0;
        header = null;
        currentHeaderId = null;
    }
 
    @Override
    public boolean performItemClick(View view, int position, long id) {
        if(view instanceof WrapperView){
            view = ((WrapperView) view).item;
        }
        return super.performItemClick(view, position, id);
    }
 
    /**
     * can only be set to false if headers are sticky, not compatible with
     * fading edges
     */
    @Override
    public void setVerticalFadingEdgeEnabled(boolean verticalFadingEdgeEnabled) {
        if (areHeadersSticky) {
            super.setVerticalFadingEdgeEnabled(false);
        } else {
            super.setVerticalFadingEdgeEnabled(verticalFadingEdgeEnabled);
        }
    }
 
    @Override
    public void setDivider(Drawable divider) {
        this.divider = divider;
        if(divider != null){
            int dividerDrawableHeight = divider.getIntrinsicHeight();
            if(dividerDrawableHeight>=0){
                setDividerHeight(dividerDrawableHeight);
            }
        }
        if (adapter != null) {
            adapter.setDivider(divider);
            requestLayout();
            invalidate();
        }
    }
 
    @Override
    public void setDividerHeight(int height) {
        dividerHeight = height;
        if (adapter != null) {
            adapter.setDividerHeight(height);
            requestLayout();
            invalidate();
        }
    }
 
    @Override
    public void setOnScrollListener(OnScrollListener l) {
        scrollListener = l;
    }
 
    public void setAreHeadersSticky(boolean areHeadersSticky) {
        if (this.areHeadersSticky != areHeadersSticky) {
            if (areHeadersSticky) {
                super.setVerticalFadingEdgeEnabled(false);
            }
            requestLayout();
            this.areHeadersSticky = areHeadersSticky;
        }
    }
 
    public boolean getAreHeadersSticky() {
        return areHeadersSticky;
    }
 
    @Override
    public void setAdapter(ListAdapter adapter) {
        if (!clipToPaddingHasBeenSet) {
            clippingToPadding = true;
        }
        if (!(adapter instanceof StickyListHeadersAdapter)) {
            throw new IllegalArgumentException(
                    "Adapter must implement StickyListHeadersAdapter");
        }
        this.adapter = new StickyListHeadersAdapterWrapper(getContext(),
                (StickyListHeadersAdapter) adapter);
        this.adapter.setDivider(divider);
        this.adapter.setDividerHeight(dividerHeight);
        this.adapter.registerDataSetObserver(dataSetChangedObserver);
        this.adapter.setOnHeaderClickListener(addapterHeaderClickListener);
        reset();
        super.setAdapter(this.adapter);
    }
 
    @Override
    protected void dispatchDraw(Canvas canvas) {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.FROYO) {
            scrollChanged(getFirstVisiblePosition());
        }
        super.dispatchDraw(canvas);
        if (header == null || !areHeadersSticky) {
            return;
        }
 
        int headerHeight = getHeaderHeight();
        int top = headerBottomPosition - headerHeight;
        clippingRect.left = getPaddingLeft();
        clippingRect.right = getWidth() - getPaddingRight();
        clippingRect.bottom = top + headerHeight;
        if (clippingToPadding) {
            clippingRect.top = getPaddingTop();
        } else {
            clippingRect.top = 0;
        }
 
        canvas.save();
        canvas.clipRect(clippingRect);
        canvas.translate(getPaddingLeft(), top);
        header.draw(canvas);
        canvas.restore();
    }
 
    private void measureHeader() {
        int widthMeasureSpec = MeasureSpec.makeMeasureSpec(getWidth(),
                MeasureSpec.EXACTLY);
        int heightMeasureSpec = 0;
 
        ViewGroup.LayoutParams params = header.getLayoutParams();
        if (params != null && params.height > 0) {
            heightMeasureSpec = MeasureSpec.makeMeasureSpec(params.height, MeasureSpec.EXACTLY);
        } else {
            heightMeasureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
        }
        header.measure(widthMeasureSpec, heightMeasureSpec);
        header.layout(getLeft() + getPaddingLeft(), 0, getRight()
                - getPaddingRight(), header.getMeasuredHeight());
    }
 
    private int getHeaderHeight() {
        if (header != null) {
            return header.getMeasuredHeight();
        }
        return 0;
    }
 
    @Override
    public void setClipToPadding(boolean clipToPadding) {
        super.setClipToPadding(clipToPadding);
        clippingToPadding = clipToPadding;
        clipToPaddingHasBeenSet = true;
    }
 
    @Override
    public void onScroll(AbsListView view, int firstVisibleItem,
            int visibleItemCount, int totalItemCount) {
        if (scrollListener != null) {
            scrollListener.onScroll(view, firstVisibleItem, visibleItemCount,
                    totalItemCount);
        }
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.FROYO) {
            scrollChanged(firstVisibleItem);
        }
    }
 
    private void scrollChanged(int firstVisibleItem) {
        if (adapter == null){
            return;
        }
        
        int adapterCount = adapter.getCount();
        if(adapterCount == 0 || !areHeadersSticky){
            
        }
 
        final int listViewHeaderCount = getHeaderViewsCount();
        firstVisibleItem = getFixedFirstVisibleItem(firstVisibleItem) - listViewHeaderCount;
        
        if(firstVisibleItem < 0 || firstVisibleItem > adapterCount-1){
            header = null;
            currentHeaderId = null;
            headerBottomPosition = -1;
            updateHeaderVisibilities();
            invalidate();
            return;
        }
 
        long newHeaderId = adapter.getHeaderId(firstVisibleItem);
        if (currentHeaderId == null || currentHeaderId != newHeaderId) {
            headerPosition = firstVisibleItem;
            header = adapter.getHeaderView(headerPosition, header,
                    this);
            measureHeader();
        }
        currentHeaderId = newHeaderId;
 
        int childCount = getChildCount();
        
        if (childCount != 0) {
            View viewToWatch = null;
            int watchingChildDistance = 99999;
            boolean viewToWatchIsFooter = false;
 
            for (int i = 0; i < childCount; i++) {
                View child = super.getChildAt(i);
                boolean childIsFooter = footerViews != null && footerViews.contains(child);
                
                int childDistance;
                if (clippingToPadding) {
                    childDistance = child.getTop() - getPaddingTop();
                } else {
                    childDistance = child.getTop();
                }
 
                if (childDistance < 0) {
                    continue;
                }
 
                if (viewToWatch == null
                        || (!viewToWatchIsFooter && !((WrapperView)viewToWatch).hasHeader())
                        || ((childIsFooter || ((WrapperView)child).hasHeader()) && childDistance < watchingChildDistance)) {
                    viewToWatch = child;
                    viewToWatchIsFooter = childIsFooter;
                    watchingChildDistance = childDistance;
                }
            }
 
            int headerHeight = getHeaderHeight();
 
            if (viewToWatch != null && (viewToWatchIsFooter || ((WrapperView)viewToWatch).hasHeader())) {
 
                if (firstVisibleItem == listViewHeaderCount && super.getChildAt(0).getTop() > 0
                        && !clippingToPadding) {
                    headerBottomPosition = 0;
                } else {
                    if (clippingToPadding) {
                        headerBottomPosition = Math.min(viewToWatch.getTop(),
                                headerHeight + getPaddingTop());
                        headerBottomPosition = headerBottomPosition < getPaddingTop() ? headerHeight
                                + getPaddingTop()
                                : headerBottomPosition;
                    } else {
                        headerBottomPosition = Math.min(viewToWatch.getTop(),
                                headerHeight);
                        headerBottomPosition = headerBottomPosition < 0 ? headerHeight
                                : headerBottomPosition;
                    }
                }
            } else {
                headerBottomPosition = headerHeight;
                if (clippingToPadding) {
                    headerBottomPosition += getPaddingTop();
                }
            }
        }
        
        updateHeaderVisibilities();
        invalidate();
    }
    
    @Override
    public void addFooterView(View v) {
        super.addFooterView(v);
        if(footerViews == null){
            footerViews = new ArrayList<>();
        }
        footerViews.add(v);
    }
    
    @Override
    public boolean removeFooterView(View v) {
        boolean removed = super.removeFooterView(v);
        if(removed){
            footerViews.remove(v);
        }
        return removed;
    }
    
    private void updateHeaderVisibilities(){
        int top = clippingToPadding ? getPaddingTop() : 0;
        int childCount = getChildCount();
        for (int i = 0; i < childCount; i++) {
            View child = super.getChildAt(i);
            if(child instanceof WrapperView){
                WrapperView wrapperViewChild = (WrapperView) child;
                if (wrapperViewChild.hasHeader()) {
                    View childHeader = wrapperViewChild.header;
                    if (wrapperViewChild.getTop() < top) {
                        childHeader.setVisibility(View.INVISIBLE);
                    } else {
                        childHeader.setVisibility(View.VISIBLE);
                    }
                }
            }
        }
    }
 
    private int getFixedFirstVisibleItem(int firstVisibleItem) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            return firstVisibleItem;
        }
 
        for (int i = 0; i < getChildCount(); i++) {
            if (getChildAt(i).getBottom() >= 0) {
                firstVisibleItem += i;
                break;
            }
        }
 
        // work around to fix bug with firstVisibleItem being to high because
        // listview does not take clipToPadding=false into account
        if (!clippingToPadding && getPaddingTop() > 0) {
            if (super.getChildAt(0).getTop() > 0) {
                if (firstVisibleItem > 0) {
                    firstVisibleItem -= 1;
                }
            }
        }
        return firstVisibleItem;
    }
 
    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        if (scrollListener != null) {
            scrollListener.onScrollStateChanged(view, scrollState);
        }
    }
 
    @Override
    public void setSelectionFromTop(int position, int y) {
        if (areHeadersSticky) {
            y += getHeaderHeight();
        }
        super.setSelectionFromTop(position, y);
    }
 
    public void setOnHeaderClickListener(
            OnHeaderClickListener onHeaderClickListener) {
        this.onHeaderClickListener = onHeaderClickListener;
    }
 
    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        int action = ev.getAction();
        if (action == MotionEvent.ACTION_DOWN
                && ev.getY() <= headerBottomPosition) {
            headerDownY = ev.getY();
            headerBeingPressed = true;
            header.setPressed(true);
            header.invalidate();
            invalidate(0, 0, getWidth(), headerBottomPosition);
            return true;
        }
        if (headerBeingPressed) {
            if (Math.abs(ev.getY() - headerDownY) < viewConfig
                    .getScaledTouchSlop()) {
                if (action == MotionEvent.ACTION_UP
                        || action == MotionEvent.ACTION_CANCEL) {
                    headerDownY = -1;
                    headerBeingPressed = false;
                    header.setPressed(false);
                    header.invalidate();
                    invalidate(0, 0, getWidth(), headerBottomPosition);
                    if (onHeaderClickListener != null) {
                        onHeaderClickListener.onHeaderClick(this, header,
                                headerPosition, currentHeaderId, true);
                    }
                }
                return true;
            } else {
                headerDownY = -1;
                headerBeingPressed = false;
                header.setPressed(false);
                header.invalidate();
                invalidate(0, 0, getWidth(), headerBottomPosition);
            }
        }
        return super.onTouchEvent(ev);
    }
 
}