src/com/android/launcher3/BaseRecyclerView.java - platform/packages/apps/Launcher3 - Gitiles

 /*
  * Copyright (C) 2015 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.launcher3;

 import android.animation.ObjectAnimator;
 import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.Paint;
 import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.support.v7.widget.RecyclerView;
 import android.util.AttributeSet;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewConfiguration;

 import com.android.launcher3.util.Thunk;

 /**
  * A base {@link RecyclerView}, which does the following:
  * <ul>
  *   <li> NOT intercept a touch unless the scrolling velocity is below a predefined threshold.
  *   <li> Enable fast scroller.
  * </ul>
  */
 public class BaseRecyclerView extends RecyclerView
         implements RecyclerView.OnItemTouchListener {

     private static final int SCROLL_DELTA_THRESHOLD_DP = 4;

     /** Keeps the last known scrolling delta/velocity along y-axis. */
     @Thunk int mDy = 0;
     private float mDeltaThreshold;

     //
     // Keeps track of variables required for the second function of this class: fast scroller.
     //

     private static final float FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR = 1.5f;

     /**
      * The current scroll state of the recycler view.  We use this in updateVerticalScrollbarBounds()
      * and scrollToPositionAtProgress() to determine the scroll position of the recycler view so
      * that we can calculate what the scroll bar looks like, and where to jump to from the fast
      * scroller.
      */
     public static class ScrollPositionState {
         // The index of the first visible row
         public int rowIndex;
         // The offset of the first visible row
         public int rowTopOffset;
         // The height of a given row (they are currently all the same height)
         public int rowHeight;
     }
     // Should be maintained inside overriden method #updateVerticalScrollbarBounds
     public ScrollPositionState scrollPosState = new ScrollPositionState();
     public Rect verticalScrollbarBounds = new Rect();

     private boolean mDraggingFastScroller;

     private Drawable mScrollbar;
     private Drawable mFastScrollerBg;
     private Rect mTmpFastScrollerInvalidateRect = new Rect();
     private Rect mFastScrollerBounds = new Rect();

     private String mFastScrollSectionName;
     private Paint mFastScrollTextPaint;
     private Rect mFastScrollTextBounds = new Rect();
     private float mFastScrollAlpha;

     private int mDownX;
     private int mDownY;
     private int mLastY;
     private int mScrollbarWidth;
     private int mScrollbarInset;
     private Rect mBackgroundPadding = new Rect();


     public BaseRecyclerView(Context context) {
         this(context, null);
     }

     public BaseRecyclerView(Context context, AttributeSet attrs) {
         this(context, attrs, 0);
     }

     public BaseRecyclerView(Context context, AttributeSet attrs, int defStyleAttr) {
         super(context, attrs, defStyleAttr);
         mDeltaThreshold = getResources().getDisplayMetrics().density * SCROLL_DELTA_THRESHOLD_DP;

         ScrollListener listener = new ScrollListener();
         setOnScrollListener(listener);

         Resources res = context.getResources();
         int fastScrollerSize = res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_popup_size);
         mScrollbar = res.getDrawable(R.drawable.all_apps_scrollbar_thumb);
         mFastScrollerBg = res.getDrawable(R.drawable.all_apps_fastscroll_bg);
         mFastScrollerBg.setBounds(0, 0, fastScrollerSize, fastScrollerSize);
         mFastScrollTextPaint = new Paint();
         mFastScrollTextPaint.setColor(Color.WHITE);
         mFastScrollTextPaint.setAntiAlias(true);
         mFastScrollTextPaint.setTextSize(res.getDimensionPixelSize(
                 R.dimen.all_apps_fast_scroll_text_size));
         mScrollbarWidth = res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_bar_width);
         mScrollbarInset =
                 res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_scrubber_touch_inset);
         setFastScrollerAlpha(mFastScrollAlpha);
         setOverScrollMode(View.OVER_SCROLL_NEVER);
     }

     private class ScrollListener extends OnScrollListener {
         public ScrollListener() {
             // Do nothing
         }

         @Override
         public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
             mDy = dy;
         }
     }

     @Override
     protected void onFinishInflate() {
         super.onFinishInflate();
         addOnItemTouchListener(this);
     }

     /**
      * We intercept the touch handling only to support fast scrolling when initiated from the
      * scroll bar.  Otherwise, we fall back to the default RecyclerView touch handling.
      */
     @Override
     public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent ev) {
         return handleTouchEvent(ev);
     }

     @Override
     public void onTouchEvent(RecyclerView rv, MotionEvent ev) {
         handleTouchEvent(ev);
     }

     /**
      * Handles the touch event and determines whether to show the fast scroller (or updates it if
      * it is already showing).
      */
     private boolean handleTouchEvent(MotionEvent ev) {
         ViewConfiguration config = ViewConfiguration.get(getContext());

         int action = ev.getAction();
         int x = (int) ev.getX();
         int y = (int) ev.getY();
         switch (action) {
             case MotionEvent.ACTION_DOWN:
                 // Keep track of the down positions
                 mDownX = x;
                 mDownY = mLastY = y;
                 if (shouldStopScroll(ev)) {
                     stopScroll();
                 }
                 break;
             case MotionEvent.ACTION_MOVE:
                 // Check if we are scrolling
                 if (!mDraggingFastScroller && isPointNearScrollbar(mDownX, mDownY) &&
                         Math.abs(y - mDownY) > config.getScaledTouchSlop()) {
                     getParent().requestDisallowInterceptTouchEvent(true);
                     mDraggingFastScroller = true;
                     animateFastScrollerVisibility(true);
                 }
                 if (mDraggingFastScroller) {
                     mLastY = y;

                     // Scroll to the right position, and update the section name
                     int top = getPaddingTop() + (mFastScrollerBg.getBounds().height() / 2);
                     int bottom = getHeight() - getPaddingBottom() -
                             (mFastScrollerBg.getBounds().height() / 2);
                     float boundedY = (float) Math.max(top, Math.min(bottom, y));
                     mFastScrollSectionName = scrollToPositionAtProgress((boundedY - top) /
                             (bottom - top));

                     // Combine the old and new fast scroller bounds to create the full invalidate
                     // rect
                     mTmpFastScrollerInvalidateRect.set(mFastScrollerBounds);
                     updateFastScrollerBounds();
                     mTmpFastScrollerInvalidateRect.union(mFastScrollerBounds);
                     invalidateFastScroller(mTmpFastScrollerInvalidateRect);
                 }
                 break;
             case MotionEvent.ACTION_UP:
             case MotionEvent.ACTION_CANCEL:
                 mDraggingFastScroller = false;
                 animateFastScrollerVisibility(false);
                 break;
         }
         return mDraggingFastScroller;
     }

     public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
         // DO NOT REMOVE, NEEDED IMPLEMENTATION FOR M BUILDS
     }

     /**
      * Returns whether this {@link MotionEvent} should trigger the scroll to be stopped.
      */
     protected boolean shouldStopScroll(MotionEvent ev) {
         if (ev.getAction() == MotionEvent.ACTION_DOWN) {
             if ((Math.abs(mDy) < mDeltaThreshold &&
                     getScrollState() != RecyclerView.SCROLL_STATE_IDLE)) {
                 // now the touch events are being passed to the {@link WidgetCell} until the
                 // touch sequence goes over the touch slop.
                 return true;
             }
         }
         return false;
     }

     @Override
     protected void dispatchDraw(Canvas canvas) {
         super.dispatchDraw(canvas);
         drawVerticalScrubber(canvas);
         drawFastScrollerPopup(canvas);
     }

     /**
      * Draws the vertical scrollbar.
      */
     private void drawVerticalScrubber(Canvas canvas) {
         updateVerticalScrollbarBounds();

         // Draw the scroll bar
         int restoreCount = canvas.save(Canvas.MATRIX_SAVE_FLAG);
         canvas.translate(verticalScrollbarBounds.left, verticalScrollbarBounds.top);
         mScrollbar.setBounds(0, 0, mScrollbarWidth, verticalScrollbarBounds.height());
         mScrollbar.draw(canvas);
         canvas.restoreToCount(restoreCount);
     }

     /**
      * Draws the fast scroller popup.
      */
     private void drawFastScrollerPopup(Canvas canvas) {
         if (mFastScrollAlpha > 0f && mFastScrollSectionName != null && !mFastScrollSectionName.isEmpty()) {
             // Draw the fast scroller popup
             int restoreCount = canvas.save(Canvas.MATRIX_SAVE_FLAG);
             canvas.translate(mFastScrollerBounds.left, mFastScrollerBounds.top);
             mFastScrollerBg.setAlpha((int) (mFastScrollAlpha * 255));
             mFastScrollerBg.draw(canvas);
             mFastScrollTextPaint.setAlpha((int) (mFastScrollAlpha * 255));
             mFastScrollTextPaint.getTextBounds(mFastScrollSectionName, 0,
                     mFastScrollSectionName.length(), mFastScrollTextBounds);
             float textWidth = mFastScrollTextPaint.measureText(mFastScrollSectionName);
             canvas.drawText(mFastScrollSectionName,
                     (mFastScrollerBounds.width() - textWidth) / 2,
                     mFastScrollerBounds.height() -
                             (mFastScrollerBounds.height() - mFastScrollTextBounds.height()) / 2,
                     mFastScrollTextPaint);
             canvas.restoreToCount(restoreCount);
         }
     }

     /**
      * Returns the scroll bar width.
      */
     public int getScrollbarWidth() {
         return mScrollbarWidth;
     }

     /**
      * Sets the fast scroller alpha.
      */
     public void setFastScrollerAlpha(float alpha) {
         mFastScrollAlpha = alpha;
         invalidateFastScroller(mFastScrollerBounds);
     }

     /**
      * Maps the touch (from 0..1) to the adapter position that should be visible.
      * <p>Override in each subclass of this base class.
      */
     public String scrollToPositionAtProgress(float touchFraction) {
         return null;
     }

     /**
      * Updates the bounds for the scrollbar.
      * <p>Override in each subclass of this base class.
      */
     public void updateVerticalScrollbarBounds() {};

     /**
      * Animates the visibility of the fast scroller popup.
      */
     private void animateFastScrollerVisibility(boolean visible) {
         ObjectAnimator anim = ObjectAnimator.ofFloat(this, "fastScrollerAlpha", visible ? 1f : 0f);
         anim.setDuration(visible ? 200 : 150);
         anim.start();
     }

     /**
      * Invalidates the fast scroller popup.
      */
     protected void invalidateFastScroller(Rect bounds) {
         invalidate(bounds.left, bounds.top, bounds.right, bounds.bottom);
     }

     /**
      * Returns whether a given point is near the scrollbar.
      */
     private boolean isPointNearScrollbar(int x, int y) {
         // Check if we are scrolling
         updateVerticalScrollbarBounds();
         verticalScrollbarBounds.inset(mScrollbarInset, mScrollbarInset);
         return verticalScrollbarBounds.contains(x, y);
     }

     /**
      * Updates the bounds for the fast scroller.
      */
     private void updateFastScrollerBounds() {
         if (mFastScrollAlpha > 0f && !mFastScrollSectionName.isEmpty()) {
             int x;
             int y;

             // Calculate the position for the fast scroller popup
             Rect bgBounds = mFastScrollerBg.getBounds();
             if (Utilities.isRtl(getResources())) {
                 x = mBackgroundPadding.left + getScrollBarSize();
             } else {
                 x = getWidth() - getPaddingRight() - getScrollBarSize() - bgBounds.width();
             }
             y = mLastY - (int) (FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR * bgBounds.height());
             y = Math.max(getPaddingTop(), Math.min(y, getHeight() - getPaddingBottom() -
                     bgBounds.height()));
             mFastScrollerBounds.set(x, y, x + bgBounds.width(), y + bgBounds.height());
         } else {
             mFastScrollerBounds.setEmpty();
         }
     }
 }
	/*
	* Copyright (C) 2015 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.launcher3;

	import android.animation.ObjectAnimator;
	import android.content.Context;
	import android.content.res.Resources;
	import android.graphics.Canvas;
	import android.graphics.Color;
	import android.graphics.Paint;
	import android.graphics.Rect;
	import android.graphics.drawable.Drawable;
	import android.support.v7.widget.RecyclerView;
	import android.util.AttributeSet;
	import android.view.MotionEvent;
	import android.view.View;
	import android.view.ViewConfiguration;

	import com.android.launcher3.util.Thunk;

	/**
	* A base {@link RecyclerView}, which does the following:
	* <ul>
	* <li> NOT intercept a touch unless the scrolling velocity is below a predefined threshold.
	* <li> Enable fast scroller.
	* </ul>
	*/
	public class BaseRecyclerView extends RecyclerView
	implements RecyclerView.OnItemTouchListener {

	private static final int SCROLL_DELTA_THRESHOLD_DP = 4;

	/** Keeps the last known scrolling delta/velocity along y-axis. */
	@Thunk int mDy = 0;
	private float mDeltaThreshold;

	//
	// Keeps track of variables required for the second function of this class: fast scroller.
	//

	private static final float FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR = 1.5f;

	/**
	* The current scroll state of the recycler view. We use this in updateVerticalScrollbarBounds()
	* and scrollToPositionAtProgress() to determine the scroll position of the recycler view so
	* that we can calculate what the scroll bar looks like, and where to jump to from the fast
	* scroller.
	*/
	public static class ScrollPositionState {
	// The index of the first visible row
	public int rowIndex;
	// The offset of the first visible row
	public int rowTopOffset;
	// The height of a given row (they are currently all the same height)
	public int rowHeight;
	}
	// Should be maintained inside overriden method #updateVerticalScrollbarBounds
	public ScrollPositionState scrollPosState = new ScrollPositionState();
	public Rect verticalScrollbarBounds = new Rect();

	private boolean mDraggingFastScroller;

	private Drawable mScrollbar;
	private Drawable mFastScrollerBg;
	private Rect mTmpFastScrollerInvalidateRect = new Rect();
	private Rect mFastScrollerBounds = new Rect();

	private String mFastScrollSectionName;
	private Paint mFastScrollTextPaint;
	private Rect mFastScrollTextBounds = new Rect();
	private float mFastScrollAlpha;

	private int mDownX;
	private int mDownY;
	private int mLastY;
	private int mScrollbarWidth;
	private int mScrollbarInset;
	private Rect mBackgroundPadding = new Rect();



	public BaseRecyclerView(Context context) {
	this(context, null);
	}

	public BaseRecyclerView(Context context, AttributeSet attrs) {
	this(context, attrs, 0);
	}

	public BaseRecyclerView(Context context, AttributeSet attrs, int defStyleAttr) {
	super(context, attrs, defStyleAttr);
	mDeltaThreshold = getResources().getDisplayMetrics().density * SCROLL_DELTA_THRESHOLD_DP;

	ScrollListener listener = new ScrollListener();
	setOnScrollListener(listener);

	Resources res = context.getResources();
	int fastScrollerSize = res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_popup_size);
	mScrollbar = res.getDrawable(R.drawable.all_apps_scrollbar_thumb);
	mFastScrollerBg = res.getDrawable(R.drawable.all_apps_fastscroll_bg);
	mFastScrollerBg.setBounds(0, 0, fastScrollerSize, fastScrollerSize);
	mFastScrollTextPaint = new Paint();
	mFastScrollTextPaint.setColor(Color.WHITE);
	mFastScrollTextPaint.setAntiAlias(true);
	mFastScrollTextPaint.setTextSize(res.getDimensionPixelSize(
	R.dimen.all_apps_fast_scroll_text_size));
	mScrollbarWidth = res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_bar_width);
	mScrollbarInset =
	res.getDimensionPixelSize(R.dimen.all_apps_fast_scroll_scrubber_touch_inset);
	setFastScrollerAlpha(mFastScrollAlpha);
	setOverScrollMode(View.OVER_SCROLL_NEVER);
	}

	private class ScrollListener extends OnScrollListener {
	public ScrollListener() {
	// Do nothing
	}

	@Override
	public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
	mDy = dy;
	}
	}

	@Override
	protected void onFinishInflate() {
	super.onFinishInflate();
	addOnItemTouchListener(this);
	}

	/**
	* We intercept the touch handling only to support fast scrolling when initiated from the
	* scroll bar. Otherwise, we fall back to the default RecyclerView touch handling.
	*/
	@Override
	public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent ev) {
	return handleTouchEvent(ev);
	}

	@Override
	public void onTouchEvent(RecyclerView rv, MotionEvent ev) {
	handleTouchEvent(ev);
	}

	/**
	* Handles the touch event and determines whether to show the fast scroller (or updates it if
	* it is already showing).
	*/
	private boolean handleTouchEvent(MotionEvent ev) {
	ViewConfiguration config = ViewConfiguration.get(getContext());

	int action = ev.getAction();
	int x = (int) ev.getX();
	int y = (int) ev.getY();
	switch (action) {
	case MotionEvent.ACTION_DOWN:
	// Keep track of the down positions
	mDownX = x;
	mDownY = mLastY = y;
	if (shouldStopScroll(ev)) {
	stopScroll();
	}
	break;
	case MotionEvent.ACTION_MOVE:
	// Check if we are scrolling
	if (!mDraggingFastScroller && isPointNearScrollbar(mDownX, mDownY) &&
	Math.abs(y - mDownY) > config.getScaledTouchSlop()) {
	getParent().requestDisallowInterceptTouchEvent(true);
	mDraggingFastScroller = true;
	animateFastScrollerVisibility(true);
	}
	if (mDraggingFastScroller) {
	mLastY = y;

	// Scroll to the right position, and update the section name
	int top = getPaddingTop() + (mFastScrollerBg.getBounds().height() / 2);
	int bottom = getHeight() - getPaddingBottom() -
	(mFastScrollerBg.getBounds().height() / 2);
	float boundedY = (float) Math.max(top, Math.min(bottom, y));
	mFastScrollSectionName = scrollToPositionAtProgress((boundedY - top) /
	(bottom - top));

	// Combine the old and new fast scroller bounds to create the full invalidate
	// rect
	mTmpFastScrollerInvalidateRect.set(mFastScrollerBounds);
	updateFastScrollerBounds();
	mTmpFastScrollerInvalidateRect.union(mFastScrollerBounds);
	invalidateFastScroller(mTmpFastScrollerInvalidateRect);
	}
	break;
	case MotionEvent.ACTION_UP:
	case MotionEvent.ACTION_CANCEL:
	mDraggingFastScroller = false;
	animateFastScrollerVisibility(false);
	break;
	}
	return mDraggingFastScroller;
	}

	public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
	// DO NOT REMOVE, NEEDED IMPLEMENTATION FOR M BUILDS
	}

	/**
	* Returns whether this {@link MotionEvent} should trigger the scroll to be stopped.
	*/
	protected boolean shouldStopScroll(MotionEvent ev) {
	if (ev.getAction() == MotionEvent.ACTION_DOWN) {
	if ((Math.abs(mDy) < mDeltaThreshold &&
	getScrollState() != RecyclerView.SCROLL_STATE_IDLE)) {
	// now the touch events are being passed to the {@link WidgetCell} until the
	// touch sequence goes over the touch slop.
	return true;
	}
	}
	return false;
	}

	@Override
	protected void dispatchDraw(Canvas canvas) {
	super.dispatchDraw(canvas);
	drawVerticalScrubber(canvas);
	drawFastScrollerPopup(canvas);
	}

	/**
	* Draws the vertical scrollbar.
	*/
	private void drawVerticalScrubber(Canvas canvas) {
	updateVerticalScrollbarBounds();

	// Draw the scroll bar
	int restoreCount = canvas.save(Canvas.MATRIX_SAVE_FLAG);
	canvas.translate(verticalScrollbarBounds.left, verticalScrollbarBounds.top);
	mScrollbar.setBounds(0, 0, mScrollbarWidth, verticalScrollbarBounds.height());
	mScrollbar.draw(canvas);
	canvas.restoreToCount(restoreCount);
	}

	/**
	* Draws the fast scroller popup.
	*/
	private void drawFastScrollerPopup(Canvas canvas) {
	if (mFastScrollAlpha > 0f && mFastScrollSectionName != null && !mFastScrollSectionName.isEmpty()) {
	// Draw the fast scroller popup
	int restoreCount = canvas.save(Canvas.MATRIX_SAVE_FLAG);
	canvas.translate(mFastScrollerBounds.left, mFastScrollerBounds.top);
	mFastScrollerBg.setAlpha((int) (mFastScrollAlpha * 255));
	mFastScrollerBg.draw(canvas);
	mFastScrollTextPaint.setAlpha((int) (mFastScrollAlpha * 255));
	mFastScrollTextPaint.getTextBounds(mFastScrollSectionName, 0,
	mFastScrollSectionName.length(), mFastScrollTextBounds);
	float textWidth = mFastScrollTextPaint.measureText(mFastScrollSectionName);
	canvas.drawText(mFastScrollSectionName,
	(mFastScrollerBounds.width() - textWidth) / 2,
	mFastScrollerBounds.height() -
	(mFastScrollerBounds.height() - mFastScrollTextBounds.height()) / 2,
	mFastScrollTextPaint);
	canvas.restoreToCount(restoreCount);
	}
	}

	/**
	* Returns the scroll bar width.
	*/
	public int getScrollbarWidth() {
	return mScrollbarWidth;
	}

	/**
	* Sets the fast scroller alpha.
	*/
	public void setFastScrollerAlpha(float alpha) {
	mFastScrollAlpha = alpha;
	invalidateFastScroller(mFastScrollerBounds);
	}

	/**
	* Maps the touch (from 0..1) to the adapter position that should be visible.
	* <p>Override in each subclass of this base class.
	*/
	public String scrollToPositionAtProgress(float touchFraction) {
	return null;
	}

	/**
	* Updates the bounds for the scrollbar.
	* <p>Override in each subclass of this base class.
	*/
	public void updateVerticalScrollbarBounds() {};

	/**
	* Animates the visibility of the fast scroller popup.
	*/
	private void animateFastScrollerVisibility(boolean visible) {
	ObjectAnimator anim = ObjectAnimator.ofFloat(this, "fastScrollerAlpha", visible ? 1f : 0f);
	anim.setDuration(visible ? 200 : 150);
	anim.start();
	}

	/**
	* Invalidates the fast scroller popup.
	*/
	protected void invalidateFastScroller(Rect bounds) {
	invalidate(bounds.left, bounds.top, bounds.right, bounds.bottom);
	}

	/**
	* Returns whether a given point is near the scrollbar.
	*/
	private boolean isPointNearScrollbar(int x, int y) {
	// Check if we are scrolling
	updateVerticalScrollbarBounds();
	verticalScrollbarBounds.inset(mScrollbarInset, mScrollbarInset);
	return verticalScrollbarBounds.contains(x, y);
	}

	/**
	* Updates the bounds for the fast scroller.
	*/
	private void updateFastScrollerBounds() {
	if (mFastScrollAlpha > 0f && !mFastScrollSectionName.isEmpty()) {
	int x;
	int y;

	// Calculate the position for the fast scroller popup
	Rect bgBounds = mFastScrollerBg.getBounds();
	if (Utilities.isRtl(getResources())) {
	x = mBackgroundPadding.left + getScrollBarSize();
	} else {
	x = getWidth() - getPaddingRight() - getScrollBarSize() - bgBounds.width();
	}
	y = mLastY - (int) (FAST_SCROLL_OVERLAY_Y_OFFSET_FACTOR * bgBounds.height());
	y = Math.max(getPaddingTop(), Math.min(y, getHeight() - getPaddingBottom() -
	bgBounds.height()));
	mFastScrollerBounds.set(x, y, x + bgBounds.width(), y + bgBounds.height());
	} else {
	mFastScrollerBounds.setEmpty();
	}
	}
	}