content: /*
   * Copyright (C) 2006 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.
   */
  /*
   * Revised 5/19/2010 by GORGES
   * Now supports two-dimensional view scrolling
   * http://GORGES.us
   */
   
  package me.lancer.airfree.view;
   
  import java.util.List;
   
  import android.content.Context;
  import android.graphics.Rect;
  import android.util.AttributeSet;
  import android.view.FocusFinder;
  import android.view.KeyEvent;
  import android.view.MotionEvent;
  import android.view.VelocityTracker;
  import android.view.View;
  import android.view.ViewConfiguration;
  import android.view.ViewGroup;
  import android.view.ViewParent;
  import android.view.animation.AnimationUtils;
  import android.widget.FrameLayout;
  import android.widget.Scroller;
  
  public class ScrollViewer extends FrameLayout {
  
  	public interface ScrollViewerListener {
  	    abstract void onScrollChanged(ScrollViewer scrollView, int x, int y, int oldx, int oldy);
  	}
  
  	private ScrollViewerListener ScrollViewerListener = null;
  
  	static final int ANIMATED_SCROLL_GAP = 250;
  	static final float MAX_SCROLL_FACTOR = 0.5f;
  
  	private long mLastScroll;
  
  	private final Rect mTempRect = new Rect();
  	private Scroller mScroller;
  
  	private boolean scrollEnabled = true;
  	
  	/**
  	 * Flag to indicate that we are moving focus ourselves. This is so the
  	 * code that watches for focus changes initiated outside this TwoDScrollView
  	 * knows that it does not have to do anything.
  	 */
  	private boolean mTwoDScrollViewMovedFocus;
  
  	/**
  	 * Position of the last motion event.
  	 */
  	private float mLastMotionY;
  	private float mLastMotionX;
  
  	/**
  	 * True when the layout has changed but the traversal has not come through yet.
  	 * Ideally the view hierarchy would keep track of this for us.
  	 */
  	private boolean mIsLayoutDirty = true;
  
  	/**
  	 * The child to give focus to in the event that a child has requested focus while the
  	 * layout is dirty. This prevents the scroll from being wrong if the child has not been
  	 * laid out before requesting focus.
  	 */
  	private View mChildToScrollTo = null;
  
  	/**
  	 * True if the user is currently dragging this TwoDScrollView around. This is
  	 * not the same as 'is being flinged', which can be checked by
  	 * mScroller.isFinished() (flinging begins when the user lifts his finger).
  	 */
  	private boolean mIsBeingDragged = false;
  
  	/**
  	 * Determines speed during touch scrolling
  	 */
  	private VelocityTracker mVelocityTracker;
  
  	/**
  	 * Whether arrow scrolling is animated.
  	 */
  	private int mTouchSlop;
  	private int mMinimumVelocity;
  	private int mMaximumVelocity;
  
  	public ScrollViewer(Context context) {
  		super(context);
  		initTwoDScrollView();
  	}
  
  	public ScrollViewer(Context context, AttributeSet attrs) {
  		super(context, attrs);
  		initTwoDScrollView();
  	}
  
  	public ScrollViewer(Context context, AttributeSet attrs, int defStyle) {
  		super(context, attrs, defStyle);
  		initTwoDScrollView();
  	}
  
  	@Override
  	protected float getTopFadingEdgeStrength() {
  		if (getChildCount() == 0) {
  			return 0.0f;
  		}
  		final int length = getVerticalFadingEdgeLength();
  		if (getScrollY() < length) {
  			return getScrollY() / (float) length;
  		}
  		return 1.0f;
  	}
  
  	@Override
  	protected float getBottomFadingEdgeStrength() {
  		if (getChildCount() == 0) {
  			return 0.0f;
  		}
  		final int length = getVerticalFadingEdgeLength();
  		final int bottomEdge = getHeight() - getPaddingBottom();
  		final int span = getChildAt(0).getBottom() - getScrollY() - bottomEdge;
  		if (span < length) {
  			return span / (float) length;
  		}
  		return 1.0f;
  	}
  
  	@Override
  	protected float getLeftFadingEdgeStrength() {
  		if (getChildCount() == 0) {
  			return 0.0f;
  		}
  		final int length = getHorizontalFadingEdgeLength();
  		if (getScrollX() < length) {
  			return getScrollX() / (float) length;
  		}
  		return 1.0f;
  	}
  
  	@Override
  	protected float getRightFadingEdgeStrength() {
  		if (getChildCount() == 0) {
  			return 0.0f;
  		}
  		final int length = getHorizontalFadingEdgeLength();
  		final int rightEdge = getWidth() - getPaddingRight();
  		final int span = getChildAt(0).getRight() - getScrollX() - rightEdge;
  		if (span < length) {
  			return span / (float) length;
  		}
  		return 1.0f;
  	}
  
  	/**
  	 * Disable/Enable scrolling
  	 */
  	public void setScrollEnabled(boolean enable)
  	{
  		scrollEnabled = enable;
  	}
  	
  	/**
  	 * @return The maximum amount this scroll view will scroll in response to
  	 *   an arrow event.
  	 */
  	 public int getMaxScrollAmountVertical() {
  		 return (int) (MAX_SCROLL_FACTOR * getHeight());
  	 }
  	 public int getMaxScrollAmountHorizontal() {
  		 return (int) (MAX_SCROLL_FACTOR * getWidth());
  	 }
  
  	 private void initTwoDScrollView() {
  		 mScroller = new Scroller(getContext());
  		 setFocusable(true);
  		 setDescendantFocusability(FOCUS_AFTER_DESCENDANTS);
  		 setWillNotDraw(false);
  		 final ViewConfiguration configuration = ViewConfiguration.get(getContext());
  		 mTouchSlop = configuration.getScaledTouchSlop();
  		 mMinimumVelocity = configuration.getScaledMinimumFlingVelocity();
  		 mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
  	 }
  
  	 @Override
  	 public void addView(View child) {
  		 if (getChildCount() > 0) {
  			 throw new IllegalStateException("TwoDScrollView can host only one direct child");
  		 }
  		 super.addView(child);
  	 }
  
  	 @Override
  	 public void addView(View child, int index) {
  		 if (getChildCount() > 0) {
  			 throw new IllegalStateException("TwoDScrollView can host only one direct child");
  		 }
  		 super.addView(child, index);
  	 }
  
  	 @Override
  	 public void addView(View child, ViewGroup.LayoutParams params) {
  		 if (getChildCount() > 0) {
  			 throw new IllegalStateException("TwoDScrollView can host only one direct child");
  		 }
  		 super.addView(child, params);
  	 }
  
  	 @Override
  	 public void addView(View child, int index, ViewGroup.LayoutParams params) {
  		 if (getChildCount() > 0) {
  			 throw new IllegalStateException("TwoDScrollView can host only one direct child");
  		 }
  		 super.addView(child, index, params);
  	 }
  
  	 /**
  	  * @return Returns true this TwoDScrollView can be scrolled
  	  */
  	 private boolean canScroll() {
  		 if(!scrollEnabled)
  			 return false;
  		 View child = getChildAt(0);
  		 if (child != null) {
  			 int childHeight = child.getHeight();
  			 int childWidth = child.getWidth();
  			 return (getHeight() < childHeight + getPaddingTop() + getPaddingBottom()) ||
  			 (getWidth() < childWidth + getPaddingLeft() + getPaddingRight());
  		 }
  		 return false;
  	 }
  
  	 @Override
  	 public boolean dispatchKeyEvent(KeyEvent event) {
  		 // Let the focused view and/or our descendants get the key first
  		 boolean handled = super.dispatchKeyEvent(event);
  		 if (handled) {
  			 return true;
  		 }
  		 return executeKeyEvent(event);
  	 }
  
  	 /**
  	  * You can call this function yourself to have the scroll view perform
  	  * scrolling from a key event, just as if the event had been dispatched to
  	  * it by the view hierarchy.
  	  *
  	  * @param event The key event to execute.
  	  * @return Return true if the event was handled, else false.
  	  */
  	 public boolean executeKeyEvent(KeyEvent event) {
  		 mTempRect.setEmpty();
  		 if (!canScroll()) {
  			 if (isFocused()) {
  				 View currentFocused = findFocus();
  				 if (currentFocused == this) currentFocused = null;
  				 View nextFocused = FocusFinder.getInstance().findNextFocus(this, currentFocused, View.FOCUS_DOWN);
  				 return nextFocused != null && nextFocused != this && nextFocused.requestFocus(View.FOCUS_DOWN);
  			 }
  			 return false;
  		 }
  		 boolean handled = false;
  		 if (event.getAction() == KeyEvent.ACTION_DOWN) {
  			 switch (event.getKeyCode()) {
  			 case KeyEvent.KEYCODE_DPAD_UP:
  				 if (!event.isAltPressed()) {
  					 handled = arrowScroll(View.FOCUS_UP, false);
  				 } else {
  					 handled = fullScroll(View.FOCUS_UP, false);
  				 }
  				 break;
  			 case KeyEvent.KEYCODE_DPAD_DOWN:
  				 if (!event.isAltPressed()) {
  					 handled = arrowScroll(View.FOCUS_DOWN, false);
  				 } else {
  					 handled = fullScroll(View.FOCUS_DOWN, false);
  				 }
  				 break;
  			 case KeyEvent.KEYCODE_DPAD_LEFT:
  				 if (!event.isAltPressed()) {
  					 handled = arrowScroll(View.FOCUS_LEFT, true);
  				 } else {
  					 handled = fullScroll(View.FOCUS_LEFT, true);
  				 }
  				 break;
  			 case KeyEvent.KEYCODE_DPAD_RIGHT:
  				 if (!event.isAltPressed()) {
  					 handled = arrowScroll(View.FOCUS_RIGHT, true);
  				 } else {
  					 handled = fullScroll(View.FOCUS_RIGHT, true);
  				 }
  				 break;
  			 }
  		 }
  		 return handled;
  	 }
  
  	 @Override
  	 public boolean onInterceptTouchEvent(MotionEvent ev) {
  		 /*
  		  * This method JUST determines whether we want to intercept the motion.
  		  * If we return true, onMotionEvent will be called and we do the actual
  		  * scrolling there.
  		  *
  		  * Shortcut the most recurring case: the user is in the dragging
  		  * state and he is moving his finger.  We want to intercept this
  		  * motion.
  		  */
  		 final int action = ev.getAction();
  		 if ((action == MotionEvent.ACTION_MOVE) && (mIsBeingDragged)) {
  			 return true;
  		 }
  		 if (!canScroll()) {
  			 mIsBeingDragged = false;
  			 return false;
  		 }
  		 final float y = ev.getY();
  		 final float x = ev.getX();
  		 switch (action) {
  		 case MotionEvent.ACTION_MOVE:
  			 /*
  			  * mIsBeingDragged == false, otherwise the shortcut would have caught it. Check
  			  * whether the user has moved far enough from his original down touch.
  			  */
  			 /*
  			  * Locally do absolute value. mLastMotionY is set to the y value
  			  * of the down event.
  			  */
  			 final int yDiff = (int) Math.abs(y - mLastMotionY);
  			 final int xDiff = (int) Math.abs(x - mLastMotionX);
  			 if (yDiff > mTouchSlop || xDiff > mTouchSlop) {
  				 mIsBeingDragged = true;
  			 }
  			 break;
  
  		 case MotionEvent.ACTION_DOWN:
  			 /* Remember location of down touch */
  			 mLastMotionY = y;
  			 mLastMotionX = x;
  
  			 /*
  			  * If being flinged and user touches the screen, initiate drag;
  			  * otherwise don't.  mScroller.isFinished should be false when
  			  * being flinged.
  			  */
  			 mIsBeingDragged = !mScroller.isFinished();
  			 break;
  
  		 case MotionEvent.ACTION_CANCEL:
  		 case MotionEvent.ACTION_UP:
  			 /* Release the drag */
  			 mIsBeingDragged = false;
  			 break;
  		 }
  
  		 /*
  		  * The only time we want to intercept motion events is if we are in the
  		  * drag mode.
  		  */
  		 return mIsBeingDragged;
  	 }
  
  	 @Override
  	 public boolean onTouchEvent(MotionEvent ev) {
  
  		 if (ev.getAction() == MotionEvent.ACTION_DOWN && ev.getEdgeFlags() != 0) {
  			 // Don't handle edge touches immediately -- they may actually belong to one of our
  			 // descendants.
  			 return false;
  		 }
  
  		 if (!canScroll()) {
  			 return false;
  		 }
  
  		 if (mVelocityTracker == null) {
  			 mVelocityTracker = VelocityTracker.obtain();
  		 }
  		 mVelocityTracker.addMovement(ev);
  
  		 final int action = ev.getAction();
  		 final float y = ev.getY();
  		 final float x = ev.getX();
  
  		 switch (action) {
  		 case MotionEvent.ACTION_DOWN:
  			 /*
  			  * If being flinged and user touches, stop the fling. isFinished
  			  * will be false if being flinged.
  			  */
  			 if (!mScroller.isFinished()) {
  				 mScroller.abortAnimation();
  			 }
  
  			 // Remember where the motion event started
  			 mLastMotionY = y;
  			 mLastMotionX = x;
  			 break;
  		 case MotionEvent.ACTION_MOVE:
  			 // Scroll to follow the motion event
  			 int deltaX = (int) (mLastMotionX - x);
  			 int deltaY = (int) (mLastMotionY - y);
  			 mLastMotionX = x;
  			 mLastMotionY = y;
  
  			 if (deltaX < 0) {
  				 if (getScrollX() < 0) {
  					 deltaX = 0;
  				 }
  			 } else if (deltaX > 0) {
  				 final int rightEdge = getWidth() - getPaddingRight();
  				 final int availableToScroll = getChildAt(0).getRight() - getScrollX() - rightEdge;
  				 if (availableToScroll > 0) {
  					 deltaX = Math.min(availableToScroll, deltaX);
  				 } else {
  					 deltaX = 0;
  				 }
  			 }
  			 if (deltaY < 0) {
  				 if (getScrollY() < 0) {
  					 deltaY = 0;
  				 }
  			 } else if (deltaY > 0) {
  				 final int bottomEdge = getHeight() - getPaddingBottom();
  				 final int availableToScroll = getChildAt(0).getBottom() - getScrollY() - bottomEdge;
  				 if (availableToScroll > 0) {
  					 deltaY = Math.min(availableToScroll, deltaY);
  				 } else {
  					 deltaY = 0;
  				 }
  			 }
  			 if (deltaY != 0 || deltaX != 0)
  				 scrollBy(deltaX, deltaY);
  			 break;
  		 case MotionEvent.ACTION_UP:
  			 final VelocityTracker velocityTracker = mVelocityTracker;
  			 velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
  			 int initialXVelocity = (int) velocityTracker.getXVelocity();
  			 int initialYVelocity = (int) velocityTracker.getYVelocity();
  			 if ((Math.abs(initialXVelocity) + Math.abs(initialYVelocity) > mMinimumVelocity) && getChildCount() > 0) {
  				 fling(-initialXVelocity, -initialYVelocity);
  			 }
  			 if (mVelocityTracker != null) {
  				 mVelocityTracker.recycle();
  				 mVelocityTracker = null;
  			 }
  		 }
  		 return true;
  	 }
  
  	 /**
  	  * Finds the next focusable component that fits in this View's bounds
  	  * (excluding fading edges) pretending that this View's top is located at
  	  * the parameter top.
  	  *
  	  * @param topFocus           look for a candidate is the one at the top of the bounds
  	  *                           if topFocus is true, or at the bottom of the bounds if topFocus is
  	  *                           false
  	  * @param top                the top offset of the bounds in which a focusable must be
  	  *                           found (the fading edge is assumed to start at this position)
  	  * @param preferredFocusable the View that has highest priority and will be
  	  *                           returned if it is within my bounds (null is valid)
  	  * @return the next focusable component in the bounds or null if none can be
  	  *         found
  	  */
  	 private View findFocusableViewInMyBounds(final boolean topFocus, final int top, final boolean leftFocus, final int left, View preferredFocusable) {
  		 /*
  		  * The fading edge's transparent side should be considered for focus
  		  * since it's mostly visible, so we divide the actual fading edge length
  		  * by 2.
  		  */
  		 final int verticalFadingEdgeLength = getVerticalFadingEdgeLength() / 2;
  		 final int topWithoutFadingEdge = top + verticalFadingEdgeLength;
  		 final int bottomWithoutFadingEdge = top + getHeight() - verticalFadingEdgeLength;
  		 final int horizontalFadingEdgeLength = getHorizontalFadingEdgeLength() / 2;
  		 final int leftWithoutFadingEdge = left + horizontalFadingEdgeLength;
  		 final int rightWithoutFadingEdge = left + getWidth() - horizontalFadingEdgeLength;
  
  		 if ((preferredFocusable != null)
  				 && (preferredFocusable.getTop() < bottomWithoutFadingEdge)
  				 && (preferredFocusable.getBottom() > topWithoutFadingEdge)
  				 && (preferredFocusable.getLeft() < rightWithoutFadingEdge)
  				 && (preferredFocusable.getRight() > leftWithoutFadingEdge)) {
  			 return preferredFocusable;
  		 }
  		 return findFocusableViewInBounds(topFocus, topWithoutFadingEdge, bottomWithoutFadingEdge, leftFocus, leftWithoutFadingEdge, rightWithoutFadingEdge);
  	 }
  
  	 /**
  	  * Finds the next focusable component that fits in the specified bounds.
  	  * </p>
  	  *
  	  * @param topFocus look for a candidate is the one at the top of the bounds
  	  *                 if topFocus is true, or at the bottom of the bounds if topFocus is
  	  *                 false
  	  * @param top      the top offset of the bounds in which a focusable must be
  	  *                 found
  	  * @param bottom   the bottom offset of the bounds in which a focusable must
  	  *                 be found
  	  * @return the next focusable component in the bounds or null if none can
  	  *         be found
  	  */
  	 private View findFocusableViewInBounds(boolean topFocus, int top, int bottom, boolean leftFocus, int left, int right) {
  		 List<View> focusables = getFocusables(View.FOCUS_FORWARD);
  		 View focusCandidate = null;
  
  		 /*
  		  * A fully contained focusable is one where its top is below the bound's
  		  * top, and its bottom is above the bound's bottom. A partially
  		  * contained focusable is one where some part of it is within the
  		  * bounds, but it also has some part that is not within bounds.  A fully contained
  		  * focusable is preferred to a partially contained focusable.
  		  */
  		 boolean foundFullyContainedFocusable = false;
  
  		 int count = focusables.size();
  		 for (int i = 0; i < count; i++) {
  			 View view = focusables.get(i);
  			 int viewTop = view.getTop();
  			 int viewBottom = view.getBottom();
  			 int viewLeft = view.getLeft();
  			 int viewRight = view.getRight();
  
  			 if (top < viewBottom && viewTop < bottom && left < viewRight && viewLeft < right) {
  				 /*
  				  * the focusable is in the target area, it is a candidate for
  				  * focusing
  				  */
  				 final boolean viewIsFullyContained = (top < viewTop) && (viewBottom < bottom) && (left < viewLeft) && (viewRight < right);
  				 if (focusCandidate == null) {
  					 /* No candidate, take this one */
  					 focusCandidate = view;
  					 foundFullyContainedFocusable = viewIsFullyContained;
  				 } else {
  					 final boolean viewIsCloserToVerticalBoundary =
  						 (topFocus && viewTop < focusCandidate.getTop()) ||
  						 (!topFocus && viewBottom > focusCandidate.getBottom());
  					 final boolean viewIsCloserToHorizontalBoundary =
  						 (leftFocus && viewLeft < focusCandidate.getLeft()) ||
  						 (!leftFocus && viewRight > focusCandidate.getRight());
  					 if (foundFullyContainedFocusable) {
  						 if (viewIsFullyContained && viewIsCloserToVerticalBoundary && viewIsCloserToHorizontalBoundary) {
  							 /*
  							  * We're dealing with only fully contained views, so
  							  * it has to be closer to the boundary to beat our
  							  * candidate
  							  */
  							 focusCandidate = view;
  						 }
  					 } else {
  						 if (viewIsFullyContained) {
  							 /* Any fully contained view beats a partially contained view */
  							 focusCandidate = view;
  							 foundFullyContainedFocusable = true;
  						 } else if (viewIsCloserToVerticalBoundary && viewIsCloserToHorizontalBoundary) {
  							 /*
  							  * Partially contained view beats another partially
  							  * contained view if it's closer
  							  */
  							 focusCandidate = view;
  						 }
  					 }
  				 }
  			 }
  		 }
  		 return focusCandidate;
  	 }
  
  	 /**
  	  * <p>Handles scrolling in response to a "home/end" shortcut press. This
  	  * method will scroll the view to the top or bottom and give the focus
  	  * to the topmost/bottommost component in the new visible area. If no
  	  * component is a good candidate for focus, this scrollview reclaims the
  	  * focus.</p>
  	  *
  	  * @param direction the scroll direction: {@link View#FOCUS_UP}
  	  *                  to go the top of the view or
  	  *                  {@link View#FOCUS_DOWN} to go the bottom
  	  * @return true if the key event is consumed by this method, false otherwise
  	  */
  	 public boolean fullScroll(int direction, boolean horizontal) {
  		 if (!horizontal) {
  			 boolean down = direction == View.FOCUS_DOWN;
  			 int height = getHeight();
  			 mTempRect.top = 0;
  			 mTempRect.bottom = height;
  			 if (down) {
  				 int count = getChildCount();
  				 if (count > 0) {
  					 View view = getChildAt(count - 1);
  					 mTempRect.bottom = view.getBottom();
  					 mTempRect.top = mTempRect.bottom - height;
  				 }
  			 }
  			 return scrollAndFocus(direction, mTempRect.top, mTempRect.bottom, 0, 0, 0);
  		 } else {
  			 boolean right = direction == View.FOCUS_DOWN;
  			 int width = getWidth();
  			 mTempRect.left = 0;
  			 mTempRect.right = width;
  			 if (right) {
  				 int count = getChildCount();
  				 if (count > 0) {
  					 View view = getChildAt(count - 1);
  					 mTempRect.right = view.getBottom();
  					 mTempRect.left = mTempRect.right - width;
  				 }
  			 }
  			 return scrollAndFocus(0, 0, 0, direction, mTempRect.top, mTempRect.bottom);
  		 }
  	 }
  
  	 private boolean scrollAndFocus(int directionY, int top, int bottom, int directionX, int left, int right) {
  		 boolean handled = true;
  		 int height = getHeight();
  		 int containerTop = getScrollY();
  		 int containerBottom = containerTop + height;
  		 boolean up = directionY == View.FOCUS_UP;
  		 int width = getWidth();
  		 int containerLeft = getScrollX();
  		 int containerRight = containerLeft + width;
  		 boolean leftwards = directionX == View.FOCUS_UP;
  		 View newFocused = findFocusableViewInBounds(up, top, bottom, leftwards, left, right);
  		 if (newFocused == null) {
  			 newFocused = this;
  		 }
  		 if ((top >= containerTop && bottom <= containerBottom) || (left >= containerLeft && right <= containerRight)) {
  			 handled = false;
  		 } else {
  			 int deltaY = up ? (top - containerTop) : (bottom - containerBottom);
  			 int deltaX = leftwards ? (left - containerLeft) : (right - containerRight);
  			 doScroll(deltaX, deltaY);
  		 }
  		 if (newFocused != findFocus() && newFocused.requestFocus(directionY)) {
  			 mTwoDScrollViewMovedFocus = true;
  			 mTwoDScrollViewMovedFocus = false;
  		 }
  		 return handled;
  	 }
  
  	 /**
  	  * Handle scrolling in response to an up or down arrow click.
  	  *
  	  * @param direction The direction corresponding to the arrow key that was
  	  *                  pressed
  	  * @return True if we consumed the event, false otherwise
  	  */
  	 public boolean arrowScroll(int direction, boolean horizontal) {
  		 View currentFocused = findFocus();
  		 if (currentFocused == this) currentFocused = null;
  		 View nextFocused = FocusFinder.getInstance().findNextFocus(this, currentFocused, direction);
  		 final int maxJump = horizontal ? getMaxScrollAmountHorizontal() : getMaxScrollAmountVertical();
  
  		 if (!horizontal) {
  			 if (nextFocused != null) {
  				 nextFocused.getDrawingRect(mTempRect);
  				 offsetDescendantRectToMyCoords(nextFocused, mTempRect);
  				 int scrollDelta = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
  				 doScroll(0, scrollDelta);
  				 nextFocused.requestFocus(direction);
  			 } else {
  				 // no new focus
  				 int scrollDelta = maxJump;
  				 if (direction == View.FOCUS_UP && getScrollY() < scrollDelta) {
  					 scrollDelta = getScrollY();
  				 } else if (direction == View.FOCUS_DOWN) {
  					 if (getChildCount() > 0) {
  						 int daBottom = getChildAt(0).getBottom();
  						 int screenBottom = getScrollY() + getHeight();
  						 if (daBottom - screenBottom < maxJump) {
  							 scrollDelta = daBottom - screenBottom;
  						 }
  					 }
  				 }
  				 if (scrollDelta == 0) {
  					 return false;
  				 }
  				 doScroll(0, direction == View.FOCUS_DOWN ? scrollDelta : -scrollDelta);
  			 }
  		 } else {
  			 if (nextFocused != null) {
  				 nextFocused.getDrawingRect(mTempRect);
  				 offsetDescendantRectToMyCoords(nextFocused, mTempRect);
  				 int scrollDelta = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
  				 doScroll(scrollDelta, 0);
  				 nextFocused.requestFocus(direction);
  			 } else {
  				 // no new focus
  				 int scrollDelta = maxJump;
  				 if (direction == View.FOCUS_UP && getScrollY() < scrollDelta) {
  					 scrollDelta = getScrollY();
  				 } else if (direction == View.FOCUS_DOWN) {
  					 if (getChildCount() > 0) {
  						 int daBottom = getChildAt(0).getBottom();
  						 int screenBottom = getScrollY() + getHeight();
  						 if (daBottom - screenBottom < maxJump) {
  							 scrollDelta = daBottom - screenBottom;
  						 }
  					 }
  				 }
  				 if (scrollDelta == 0) {
  					 return false;
  				 }
  				 doScroll(direction == View.FOCUS_DOWN ? scrollDelta : -scrollDelta, 0);
  			 }
  		 }
  		 return true;
  	 }
  
  	 private void doScroll(int deltaX, int deltaY) {
  		 if (deltaX != 0 || deltaY != 0) {
  			 smoothScrollBy(deltaX, deltaY);
  		 }
  	 }
  
  	 /**
  	  * Like {@link View#scrollBy}, but scroll smoothly instead of immediately.
  	  *
  	  * @param dx the number of pixels to scroll by on the X axis
  	  * @param dy the number of pixels to scroll by on the Y axis
  	  */
  	 public final void smoothScrollBy(int dx, int dy) {
  		 long duration = AnimationUtils.currentAnimationTimeMillis() - mLastScroll;
  		 if (duration > ANIMATED_SCROLL_GAP) {
  			 mScroller.startScroll(getScrollX(), getScrollY(), dx, dy);
  			 awakenScrollBars(mScroller.getDuration());
  			 invalidate();
  		 } else {
  			 if (!mScroller.isFinished()) {
  				 mScroller.abortAnimation();
  			 }
  			 scrollBy(dx, dy);
  		 }
  		 mLastScroll = AnimationUtils.currentAnimationTimeMillis();
  	 }
  
  	 /**
  	  * Like {@link #scrollTo}, but scroll smoothly instead of immediately.
  	  *
  	  * @param x the position where to scroll on the X axis
  	  * @param y the position where to scroll on the Y axis
  	  */
  	 public final void smoothScrollTo(int x, int y) {
  		 smoothScrollBy(x - getScrollX(), y - getScrollY());
  	 }
  
  	 /**
  	  * <p>The scroll range of a scroll view is the overall height of all of its
  	  * children.</p>
  	  */
  	 @Override
  	 protected int computeVerticalScrollRange() {
  		 int count = getChildCount();
  		 return count == 0 ? getHeight() : (getChildAt(0)).getBottom();
  	 }
  	 @Override
  	 protected int computeHorizontalScrollRange() {
  		 int count = getChildCount();
  		 return count == 0 ? getWidth() : (getChildAt(0)).getRight();
  	 }
  
  	 @Override
  	 protected void measureChild(View child, int parentWidthMeasureSpec, int parentHeightMeasureSpec) {
  		 ViewGroup.LayoutParams lp = child.getLayoutParams();
  		 int childWidthMeasureSpec;
  		 int childHeightMeasureSpec;
  
  		 childWidthMeasureSpec = getChildMeasureSpec(parentWidthMeasureSpec, getPaddingLeft() + getPaddingRight(), lp.width);
  		 childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
  
  		 child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
  	 }
  
  	 @Override
  	 protected void measureChildWithMargins(View child, int parentWidthMeasureSpec, int widthUsed, int parentHeightMeasureSpec, int heightUsed) {
  		 final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();
  		 final int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(lp.leftMargin + lp.rightMargin, MeasureSpec.UNSPECIFIED);
  		 final int childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(lp.topMargin + lp.bottomMargin, MeasureSpec.UNSPECIFIED);
  
  		 child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
  	 }
  
  	 @Override
  	 public void computeScroll() {
  		 if (mScroller.computeScrollOffset()) {
  			 // This is called at drawing time by ViewGroup.  We don't want to
  			 // re-show the scrollbars at this point, which scrollTo will do,
  			 // so we replicate most of scrollTo here.
  			 //
  			 //         It's a little odd to call onScrollChanged from inside the drawing.
  			 //
  			 //         It is, except when you remember that computeScroll() is used to
  			 //         animate scrolling. So unless we want to defer the onScrollChanged()
  			 //         until the end of the animated scrolling, we don't really have a
  			 //         choice here.
  			 //
  			 //         I agree.  The alternative, which I think would be worse, is to post
  			 //         something and tell the subclasses later.  This is bad because there
  			 //         will be a window where mScrollX/Y is different from what the app
  			 //         thinks it is.
  			 //
  			 int oldX = getScrollX();
  			 int oldY = getScrollY();
  			 int x = mScroller.getCurrX();
  			 int y = mScroller.getCurrY();
  			 if (getChildCount() > 0) {
  				 View child = getChildAt(0);
  				 scrollTo(clamp(x, getWidth() - getPaddingRight() - getPaddingLeft(), child.getWidth()),
  						 clamp(y, getHeight() - getPaddingBottom() - getPaddingTop(), child.getHeight()));
  			 } else {
  				 scrollTo(x, y);
  			 }
  			 if (oldX != getScrollX() || oldY != getScrollY()) {
  				 onScrollChanged(getScrollX(), getScrollY(), oldX, oldY);
  			 }
  
  			 // Keep on drawing until the animation has finished.
  			 postInvalidate();
  		 }
  	 }
  
  	 /**
  	  * Scrolls the view to the given child.
  	  *
  	  * @param child the View to scroll to
  	  */
  	 private void scrollToChild(View child) {
  		 child.getDrawingRect(mTempRect);
  		 /* Offset from child's local coordinates to TwoDScrollView coordinates */
  		 offsetDescendantRectToMyCoords(child, mTempRect);
  		 int scrollDelta = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
  		 if (scrollDelta != 0) {
  			 scrollBy(0, scrollDelta);
  		 }
  	 }
  
  	 /**
  	  * If rect is off screen, scroll just enough to get it (or at least the
  	  * first screen size chunk of it) on screen.
  	  *
  	  * @param rect      The rectangle.
  	  * @param immediate True to scroll immediately without animation
  	  * @return true if scrolling was performed
  	  */
  	 private boolean scrollToChildRect(Rect rect, boolean immediate) {
  		 final int delta = computeScrollDeltaToGetChildRectOnScreen(rect);
  		 final boolean scroll = delta != 0;
  		 if (scroll) {
  			 if (immediate) {
  				 scrollBy(0, delta);
  			 } else {
  				 smoothScrollBy(0, delta);
  			 }
  		 }
  		 return scroll;
  	 }
  
  	 /**
  	  * Compute the amount to scroll in the Y direction in order to get
  	  * a rectangle completely on the screen (or, if taller than the screen,
  	  * at least the first screen size chunk of it).
  	  *
  	  * @param rect The rect.
  	  * @return The scroll delta.
  	  */
  	 protected int computeScrollDeltaToGetChildRectOnScreen(Rect rect) {
  		 if (getChildCount() == 0) return 0;
  		 int height = getHeight();
  		 int screenTop = getScrollY();
  		 int screenBottom = screenTop + height;
  		 int fadingEdge = getVerticalFadingEdgeLength();
  		 // leave room for top fading edge as long as rect isn't at very top
  		 if (rect.top > 0) {
  			 screenTop += fadingEdge;
  		 }
  
  		 // leave room for bottom fading edge as long as rect isn't at very bottom
  		 if (rect.bottom < getChildAt(0).getHeight()) {
  			 screenBottom -= fadingEdge;
  		 }
  		 int scrollYDelta = 0;
  		 if (rect.bottom > screenBottom && rect.top > screenTop) {
  			 // need to move down to get it in view: move down just enough so
  			 // that the entire rectangle is in view (or at least the first
  			 // screen size chunk).
  			 if (rect.height() > height) {
  				 // just enough to get screen size chunk on
  				 scrollYDelta += (rect.top - screenTop);
  			 } else {
  				 // get entire rect at bottom of screen
  				 scrollYDelta += (rect.bottom - screenBottom);
  			 }
  
  			 // make sure we aren't scrolling beyond the end of our content
  			 int bottom = getChildAt(0).getBottom();
  			 int distanceToBottom = bottom - screenBottom;
  			 scrollYDelta = Math.min(scrollYDelta, distanceToBottom);
  
  		 } else if (rect.top < screenTop && rect.bottom < screenBottom) {
  			 // need to move up to get it in view: move up just enough so that
  			 // entire rectangle is in view (or at least the first screen
  			 // size chunk of it).
  
  			 if (rect.height() > height) {
  				 // screen size chunk
  				 scrollYDelta -= (screenBottom - rect.bottom);
  			 } else {
  				 // entire rect at top
  				 scrollYDelta -= (screenTop - rect.top);
  			 }
  
  			 // make sure we aren't scrolling any further than the top our content
  			 scrollYDelta = Math.max(scrollYDelta, -getScrollY());
  		 }
  		 return scrollYDelta;
  	 }
  
  	 @Override
  	 public void requestChildFocus(View child, View focused) {
  		 if (!mTwoDScrollViewMovedFocus) {
  			 if (!mIsLayoutDirty) {
  				 scrollToChild(focused);
  			 } else {
  				 // The child may not be laid out yet, we can't compute the scroll yet
  				 mChildToScrollTo = focused;
  			 }
  		 }
  		 super.requestChildFocus(child, focused);
  	 }
  
  	 /**
  	  * When looking for focus in children of a scroll view, need to be a little
  	  * more careful not to give focus to something that is scrolled off screen.
  	  *
  	  * This is more expensive than the default {@link ViewGroup}
  	  * implementation, otherwise this behavior might have been made the default.
  	  */
  	 @Override
  	 protected boolean onRequestFocusInDescendants(int direction, Rect previouslyFocusedRect) {
  		 // convert from forward / backward notation to up / down / left / right
  		 // (ugh).
  		 if (direction == View.FOCUS_FORWARD) {
  			 direction = View.FOCUS_DOWN;
  		 } else if (direction == View.FOCUS_BACKWARD) {
  			 direction = View.FOCUS_UP;
  		 }
  
  		 final View nextFocus = previouslyFocusedRect == null ?
  				 FocusFinder.getInstance().findNextFocus(this, null, direction) :
  					 FocusFinder.getInstance().findNextFocusFromRect(this,
  							 previouslyFocusedRect, direction);
  
  				 if (nextFocus == null) {
  					 return false;
  				 }
  
  				 return nextFocus.requestFocus(direction, previouslyFocusedRect);
  	 }
  
  	 @Override
  	 public boolean requestChildRectangleOnScreen(View child, Rect rectangle, boolean immediate) {
  		 // offset into coordinate space of this scroll view
  		 rectangle.offset(child.getLeft() - child.getScrollX(), child.getTop() - child.getScrollY());
  		 return scrollToChildRect(rectangle, immediate);
  	 }
  
  	 @Override
  	 public void requestLayout() {
  		 mIsLayoutDirty = true;
  		 super.requestLayout();
  	 }
  
  	 @Override
  	 protected void onLayout(boolean changed, int l, int t, int r, int b) {
  		 super.onLayout(changed, l, t, r, b);
  		 mIsLayoutDirty = false;
  		 // Give a child focus if it needs it
  		 if (mChildToScrollTo != null && isViewDescendantOf(mChildToScrollTo, this)) {
  			 scrollToChild(mChildToScrollTo);
  		 }
  		 mChildToScrollTo = null;
  
  		 // Calling this with the present values causes it to re-clam them
  		 scrollTo(getScrollX(), getScrollY());
  	 }
  
  	 @Override
  	 protected void onSizeChanged(int w, int h, int oldw, int oldh) {
  		 super.onSizeChanged(w, h, oldw, oldh);
  
  		 View currentFocused = findFocus();
  		 if (null == currentFocused || this == currentFocused)
  			 return;
  
  		 // If the currently-focused view was visible on the screen when the
  		 // screen was at the old height, then scroll the screen to make that
  		 // view visible with the new screen height.
  		 currentFocused.getDrawingRect(mTempRect);
  		 offsetDescendantRectToMyCoords(currentFocused, mTempRect);
  		 int scrollDeltaX = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
  		 int scrollDeltaY = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
  		 doScroll(scrollDeltaX, scrollDeltaY);
  	 }
  
  	 /**
  	  * Return true if child is an descendant of parent, (or equal to the parent).
  	  */
  	 private boolean isViewDescendantOf(View child, View parent) {
  		 if (child == parent) {
  			 return true;
  		 }
  
  		 final ViewParent theParent = child.getParent();
  		 return (theParent instanceof ViewGroup) && isViewDescendantOf((View) theParent, parent);
  	 }
  
  	 /**
  	  * Fling the scroll view
  	  *
  	  * @param velocityY The initial velocity in the Y direction. Positive
  	  *                  numbers mean that the finger/curor is moving down the screen,
  	  *                  which means we want to scroll towards the top.
  	  */
  	 public void fling(int velocityX, int velocityY) {
  		 if (getChildCount() > 0) {
  			 int height = getHeight() - getPaddingBottom() - getPaddingTop();
  			 int bottom = getChildAt(0).getHeight();
  			 int width = getWidth() - getPaddingRight() - getPaddingLeft();
  			 int right = getChildAt(0).getWidth();
  
  			 mScroller.fling(getScrollX(), getScrollY(), velocityX, velocityY, 0, right - width, 0, bottom - height);
  
  			 final boolean movingDown = velocityY > 0;
  			 final boolean movingRight = velocityX > 0;
  
  			 View newFocused = findFocusableViewInMyBounds(movingRight, mScroller.getFinalX(), movingDown, mScroller.getFinalY(), findFocus());
  			 if (newFocused == null) {
  				 newFocused = this;
  			 }
  
  			 if (newFocused != findFocus() && newFocused.requestFocus(movingDown ? View.FOCUS_DOWN : View.FOCUS_UP)) {
  				 mTwoDScrollViewMovedFocus = true;
  				 mTwoDScrollViewMovedFocus = false;
  			 }
  
  			 awakenScrollBars(mScroller.getDuration());
  			 invalidate();
  		 }
  	 }
  
  	 /**
  	  * {@inheritDoc}
  	  *
  	  * <p>This version also clamps the scrolling to the bounds of our child.
  	  */
  	 public void scrollTo(int x, int y) {
  		 // we rely on the fact the View.scrollBy calls scrollTo.
  		 if (getChildCount() > 0) {
  			 View child = getChildAt(0);
  			 x = clamp(x, getWidth() - getPaddingRight() - getPaddingLeft(), child.getWidth());
  			 y = clamp(y, getHeight() - getPaddingBottom() - getPaddingTop(), child.getHeight());
  			 if (x != getScrollX() || y != getScrollY()) {
  				 super.scrollTo(x, y);
  			 }
  		 }
  	 }
  
  	 private int clamp(int n, int my, int child) {
  		 if (my >= child || n < 0) {
  			 /* my >= child is this case:
  			  *                    |--------------- me ---------------|
  			  *     |------ child ------|
  			  * or
  			  *     |--------------- me ---------------|
  			  *            |------ child ------|
  			  * or
  			  *     |--------------- me ---------------|
  			  *                                  |------ child ------|
  			  *
  			  * n < 0 is this case:
  			  *     |------ me ------|
  			  *                    |-------- child --------|
  			  *     |-- mScrollX --|
  			  */
  			 return 0;
  		 }
  		 if ((my+n) > child) {
  			 /* this case:
  			  *                    |------ me ------|
  			  *     |------ child ------|
  			  *     |-- mScrollX --|
  			  */
  			 return child-my;
  		 }
  		 return n;
  	 }
  	 
  	 public void setScrollViewListener(ScrollViewerListener scrollViewListener) {
  		 this.ScrollViewerListener = scrollViewListener;
  	 }
  
  	 @Override
  	 protected void onScrollChanged(int x, int y, int oldx, int oldy) {
  		 super.onScrollChanged(x, y, oldx, oldy);
  		 if(ScrollViewerListener != null) {
  			 ScrollViewerListener.onScrollChanged(this, x, y, oldx, oldy);
  		 }
  	 }
  
  }
  