core/java/com/android/internal/widget/DecorCaptionView.java - platform/frameworks/base - Git at Google

 /*
  * 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.internal.widget;

 import android.content.Context;
 import android.graphics.Color;
 import android.graphics.Rect;
 import android.os.RemoteException;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.GestureDetector;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewConfiguration;
 import android.view.ViewGroup;
 import android.view.ViewOutlineProvider;
 import android.view.Window;

 import com.android.internal.R;
 import com.android.internal.policy.PhoneWindow;

 import java.util.ArrayList;

 /**
  * This class represents the special screen elements to control a window on freeform
  * environment.
  * As such this class handles the following things:
  * <ul>
  * <li>The caption, containing the system buttons like maximize, close and such as well as
  * allowing the user to drag the window around.</li>
  * </ul>
  * After creating the view, the function {@link #setPhoneWindow} needs to be called to make
  * the connection to it's owning PhoneWindow.
  * Note: At this time the application can change various attributes of the DecorView which
  * will break things (in settle/unexpected ways):
  * <ul>
  * <li>setOutlineProvider</li>
  * <li>setSurfaceFormat</li>
  * <li>..</li>
  * </ul>
  *
  * Although this ViewGroup has only two direct sub-Views, its behavior is more complex due to
  * overlaying caption on the content and drawing.
  *
  * First, no matter where the content View gets added, it will always be the first child and the
  * caption will be the second. This way the caption will always be drawn on top of the content when
  * overlaying is enabled.
  *
  * Second, the touch dispatch is customized to handle overlaying. This is what happens when touch
  * is dispatched on the caption area while overlaying it on content:
  * <ul>
  * <li>DecorCaptionView.onInterceptTouchEvent() will try intercepting the touch events if the
  * down action is performed on top close or maximize buttons; the reason for that is we want these
  * buttons to always work.</li>
  * <li>The content View will receive the touch event. Mind that content is actually underneath the
  * caption, so we need to introduce our own dispatch ordering. We achieve this by overriding
  * {@link #buildTouchDispatchChildList()}.</li>
  * <li>If the touch event is not consumed by the content View, it will go to the caption View
  * and the dragging logic will be executed.</li>
  * </ul>
  */
 public class DecorCaptionView extends ViewGroup implements View.OnTouchListener,
         GestureDetector.OnGestureListener {
     private final static String TAG = "DecorCaptionView";
     private PhoneWindow mOwner = null;
     private boolean mShow = false;

     // True if the window is being dragged.
     private boolean mDragging = false;

     // True when the left mouse button got released while dragging.
     private boolean mLeftMouseButtonReleased;

     private boolean mOverlayWithAppContent = false;

     private View mCaption;
     private View mContent;
     private View mMaximize;
     private View mClose;

     // Fields for detecting drag events.
     private int mTouchDownX;
     private int mTouchDownY;
     private boolean mCheckForDragging;
     private int mDragSlop;

     // Fields for detecting and intercepting click events on close/maximize.
     private ArrayList<View> mTouchDispatchList = new ArrayList<>(2);
     // We use the gesture detector to detect clicks on close/maximize buttons and to be consistent
     // with existing click detection.
     private GestureDetector mGestureDetector;
     private final Rect mCloseRect = new Rect();
     private final Rect mMaximizeRect = new Rect();
     private View mClickTarget;

     public DecorCaptionView(Context context) {
         super(context);
         init(context);
     }

     public DecorCaptionView(Context context, AttributeSet attrs) {
         super(context, attrs);
         init(context);
     }

     public DecorCaptionView(Context context, AttributeSet attrs, int defStyle) {
         super(context, attrs, defStyle);
         init(context);
     }

     private void init(Context context) {
         mDragSlop = ViewConfiguration.get(context).getScaledTouchSlop();
         mGestureDetector = new GestureDetector(context, this);
     }

     @Override
     protected void onFinishInflate() {
         super.onFinishInflate();
         mCaption = getChildAt(0);
     }

     public void setPhoneWindow(PhoneWindow owner, boolean show) {
         mOwner = owner;
         mShow = show;
         mOverlayWithAppContent = owner.isOverlayWithDecorCaptionEnabled();
         if (mOverlayWithAppContent) {
             // The caption is covering the content, so we make its background transparent to make
             // the content visible.
             mCaption.setBackgroundColor(Color.TRANSPARENT);
         }
         updateCaptionVisibility();
         // By changing the outline provider to BOUNDS, the window can remove its
         // background without removing the shadow.
         mOwner.getDecorView().setOutlineProvider(ViewOutlineProvider.BOUNDS);
         mMaximize = findViewById(R.id.maximize_window);
         mClose = findViewById(R.id.close_window);
     }

     @Override
     public boolean onInterceptTouchEvent(MotionEvent ev) {
         // If the user starts touch on the maximize/close buttons, we immediately intercept, so
         // that these buttons are always clickable.
         if (ev.getAction() == MotionEvent.ACTION_DOWN) {
             final int x = (int) ev.getX();
             final int y = (int) ev.getY();
             if (mMaximizeRect.contains(x, y)) {
                 mClickTarget = mMaximize;
             }
             if (mCloseRect.contains(x, y)) {
                 mClickTarget = mClose;
             }
         }
         return mClickTarget != null;
     }

     @Override
     public boolean onTouchEvent(MotionEvent event) {
         if (mClickTarget != null) {
             mGestureDetector.onTouchEvent(event);
             final int action = event.getAction();
             if (action == MotionEvent.ACTION_UP || action == MotionEvent.ACTION_CANCEL) {
                 mClickTarget = null;
             }
             return true;
         }
         return false;
     }

     @Override
     public boolean onTouch(View v, MotionEvent e) {
         // Note: There are no mixed events. When a new device gets used (e.g. 1. Mouse, 2. touch)
         // the old input device events get cancelled first. So no need to remember the kind of
         // input device we are listening to.
         final int x = (int) e.getX();
         final int y = (int) e.getY();
         switch (e.getActionMasked()) {
             case MotionEvent.ACTION_DOWN:
                 if (!mShow) {
                     // When there is no caption we should not react to anything.
                     return false;
                 }
                 // Checking for a drag action is started if we aren't dragging already and the
                 // starting event is either a left mouse button or any other input device.
                 if (((e.getToolType(e.getActionIndex()) != MotionEvent.TOOL_TYPE_MOUSE ||
                         (e.getButtonState() & MotionEvent.BUTTON_PRIMARY) != 0))) {
                     mCheckForDragging = true;
                     mTouchDownX = x;
                     mTouchDownY = y;
                 }
                 break;

             case MotionEvent.ACTION_MOVE:
                 if (!mDragging && mCheckForDragging && passedSlop(x, y)) {
                     mCheckForDragging = false;
                     mDragging = true;
                     mLeftMouseButtonReleased = false;
                     startMovingTask(e.getRawX(), e.getRawY());
                 } else if (mDragging && !mLeftMouseButtonReleased) {
                     if (e.getToolType(e.getActionIndex()) == MotionEvent.TOOL_TYPE_MOUSE &&
                             (e.getButtonState() & MotionEvent.BUTTON_PRIMARY) == 0) {
                         // There is no separate mouse button up call and if the user mixes mouse
                         // button drag actions, we stop dragging once he releases the button.
                         mLeftMouseButtonReleased = true;
                         break;
                     }
                 }
                 break;

             case MotionEvent.ACTION_UP:
             case MotionEvent.ACTION_CANCEL:
                 if (!mDragging) {
                     break;
                 }
                 // Abort the ongoing dragging.
                 mDragging = false;
                 return !mCheckForDragging;
         }
         return mDragging || mCheckForDragging;
     }

     @Override
     public ArrayList<View> buildTouchDispatchChildList() {
         mTouchDispatchList.ensureCapacity(3);
         if (mCaption != null) {
             mTouchDispatchList.add(mCaption);
         }
         if (mContent != null) {
             mTouchDispatchList.add(mContent);
         }
         return mTouchDispatchList;
     }

     @Override
     public boolean shouldDelayChildPressedState() {
         return false;
     }

     private boolean passedSlop(int x, int y) {
         return Math.abs(x - mTouchDownX) > mDragSlop || Math.abs(y - mTouchDownY) > mDragSlop;
     }

     /**
      * The phone window configuration has changed and the caption needs to be updated.
      * @param show True if the caption should be shown.
      */
     public void onConfigurationChanged(boolean show) {
         mShow = show;
         updateCaptionVisibility();
     }

     @Override
     public void addView(View child, int index, ViewGroup.LayoutParams params) {
         if (!(params instanceof MarginLayoutParams)) {
             throw new IllegalArgumentException(
                     "params " + params + " must subclass MarginLayoutParams");
         }
         // Make sure that we never get more then one client area in our view.
         if (index >= 2 || getChildCount() >= 2) {
             throw new IllegalStateException("DecorCaptionView can only handle 1 client view");
         }
         // To support the overlaying content in the caption, we need to put the content view as the
         // first child to get the right Z-Ordering.
         super.addView(child, 0, params);
         mContent = child;
     }

     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         final int captionHeight;
         if (mCaption.getVisibility() != View.GONE) {
             measureChildWithMargins(mCaption, widthMeasureSpec, 0, heightMeasureSpec, 0);
             captionHeight = mCaption.getMeasuredHeight();
         } else {
             captionHeight = 0;
         }
         if (mContent != null) {
             if (mOverlayWithAppContent) {
                 measureChildWithMargins(mContent, widthMeasureSpec, 0, heightMeasureSpec, 0);
             } else {
                 measureChildWithMargins(mContent, widthMeasureSpec, 0, heightMeasureSpec,
                         captionHeight);
             }
         }

         setMeasuredDimension(MeasureSpec.getSize(widthMeasureSpec),
                 MeasureSpec.getSize(heightMeasureSpec));
     }

     @Override
     protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
         final int captionHeight;
         if (mCaption.getVisibility() != View.GONE) {
             mCaption.layout(0, 0, mCaption.getMeasuredWidth(), mCaption.getMeasuredHeight());
             captionHeight = mCaption.getBottom() - mCaption.getTop();
             mMaximize.getHitRect(mMaximizeRect);
             mClose.getHitRect(mCloseRect);
         } else {
             captionHeight = 0;
             mMaximizeRect.setEmpty();
             mCloseRect.setEmpty();
         }

         if (mContent != null) {
             if (mOverlayWithAppContent) {
                 mContent.layout(0, 0, mContent.getMeasuredWidth(), mContent.getMeasuredHeight());
             } else {
                 mContent.layout(0, captionHeight, mContent.getMeasuredWidth(),
                         captionHeight + mContent.getMeasuredHeight());
             }
         }

         // This assumes that the caption bar is at the top.
         mOwner.notifyRestrictedCaptionAreaCallback(mMaximize.getLeft(), mMaximize.getTop(),
                 mClose.getRight(), mClose.getBottom());
     }
     /**
      * Determine if the workspace is entirely covered by the window.
      * @return Returns true when the window is filling the entire screen/workspace.
      **/
     private boolean isFillingScreen() {
         return (0 != ((getWindowSystemUiVisibility() | getSystemUiVisibility()) &
                 (View.SYSTEM_UI_FLAG_FULLSCREEN | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION |
                         View.SYSTEM_UI_FLAG_IMMERSIVE | View.SYSTEM_UI_FLAG_LOW_PROFILE)));
     }

     /**
      * Updates the visibility of the caption.
      **/
     private void updateCaptionVisibility() {
         // Don't show the caption if the window has e.g. entered full screen.
         boolean invisible = isFillingScreen() || !mShow;
         mCaption.setVisibility(invisible ? GONE : VISIBLE);
         mCaption.setOnTouchListener(this);
     }

     /**
      * Maximize the window by moving it to the maximized workspace stack.
      **/
     private void maximizeWindow() {
         Window.WindowControllerCallback callback = mOwner.getWindowControllerCallback();
         if (callback != null) {
             try {
                 callback.exitFreeformMode();
             } catch (RemoteException ex) {
                 Log.e(TAG, "Cannot change task workspace.");
             }
         }
     }

     public boolean isCaptionShowing() {
         return mShow;
     }

     public int getCaptionHeight() {
         return (mCaption != null) ? mCaption.getHeight() : 0;
     }

     public void removeContentView() {
         if (mContent != null) {
             removeView(mContent);
             mContent = null;
         }
     }

     public View getCaption() {
         return mCaption;
     }

     @Override
     public LayoutParams generateLayoutParams(AttributeSet attrs) {
         return new MarginLayoutParams(getContext(), attrs);
     }

     @Override
     protected LayoutParams generateDefaultLayoutParams() {
         return new MarginLayoutParams(MarginLayoutParams.MATCH_PARENT,
                 MarginLayoutParams.MATCH_PARENT);
     }

     @Override
     protected LayoutParams generateLayoutParams(LayoutParams p) {
         return new MarginLayoutParams(p);
     }

     @Override
     protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
         return p instanceof MarginLayoutParams;
     }

     @Override
     public boolean onDown(MotionEvent e) {
         return false;
     }

     @Override
     public void onShowPress(MotionEvent e) {

     }

     @Override
     public boolean onSingleTapUp(MotionEvent e) {
         if (mClickTarget == mMaximize) {
             maximizeWindow();
         } else if (mClickTarget == mClose) {
             mOwner.dispatchOnWindowDismissed(true /*finishTask*/);
         }
         return true;
     }

     @Override
     public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
         return false;
     }

     @Override
     public void onLongPress(MotionEvent e) {

     }

     @Override
     public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
         return false;
     }
 }
	/*
	* 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.internal.widget;

	import android.content.Context;
	import android.graphics.Color;
	import android.graphics.Rect;
	import android.os.RemoteException;
	import android.util.AttributeSet;
	import android.util.Log;
	import android.view.GestureDetector;
	import android.view.MotionEvent;
	import android.view.View;
	import android.view.ViewConfiguration;
	import android.view.ViewGroup;
	import android.view.ViewOutlineProvider;
	import android.view.Window;

	import com.android.internal.R;
	import com.android.internal.policy.PhoneWindow;

	import java.util.ArrayList;

	/**
	* This class represents the special screen elements to control a window on freeform
	* environment.
	* As such this class handles the following things:
	* <ul>
	* <li>The caption, containing the system buttons like maximize, close and such as well as
	* allowing the user to drag the window around.</li>
	* </ul>
	* After creating the view, the function {@link #setPhoneWindow} needs to be called to make
	* the connection to it's owning PhoneWindow.
	* Note: At this time the application can change various attributes of the DecorView which
	* will break things (in settle/unexpected ways):
	* <ul>
	* <li>setOutlineProvider</li>
	* <li>setSurfaceFormat</li>
	* <li>..</li>
	* </ul>
	*
	* Although this ViewGroup has only two direct sub-Views, its behavior is more complex due to
	* overlaying caption on the content and drawing.
	*
	* First, no matter where the content View gets added, it will always be the first child and the
	* caption will be the second. This way the caption will always be drawn on top of the content when
	* overlaying is enabled.
	*
	* Second, the touch dispatch is customized to handle overlaying. This is what happens when touch
	* is dispatched on the caption area while overlaying it on content:
	* <ul>
	* <li>DecorCaptionView.onInterceptTouchEvent() will try intercepting the touch events if the
	* down action is performed on top close or maximize buttons; the reason for that is we want these
	* buttons to always work.</li>
	* <li>The content View will receive the touch event. Mind that content is actually underneath the
	* caption, so we need to introduce our own dispatch ordering. We achieve this by overriding
	* {@link #buildTouchDispatchChildList()}.</li>
	* <li>If the touch event is not consumed by the content View, it will go to the caption View
	* and the dragging logic will be executed.</li>
	* </ul>
	*/
	public class DecorCaptionView extends ViewGroup implements View.OnTouchListener,
	GestureDetector.OnGestureListener {
	private final static String TAG = "DecorCaptionView";
	private PhoneWindow mOwner = null;
	private boolean mShow = false;

	// True if the window is being dragged.
	private boolean mDragging = false;

	// True when the left mouse button got released while dragging.
	private boolean mLeftMouseButtonReleased;

	private boolean mOverlayWithAppContent = false;

	private View mCaption;
	private View mContent;
	private View mMaximize;
	private View mClose;

	// Fields for detecting drag events.
	private int mTouchDownX;
	private int mTouchDownY;
	private boolean mCheckForDragging;
	private int mDragSlop;

	// Fields for detecting and intercepting click events on close/maximize.
	private ArrayList<View> mTouchDispatchList = new ArrayList<>(2);
	// We use the gesture detector to detect clicks on close/maximize buttons and to be consistent
	// with existing click detection.
	private GestureDetector mGestureDetector;
	private final Rect mCloseRect = new Rect();
	private final Rect mMaximizeRect = new Rect();
	private View mClickTarget;

	public DecorCaptionView(Context context) {
	super(context);
	init(context);
	}

	public DecorCaptionView(Context context, AttributeSet attrs) {
	super(context, attrs);
	init(context);
	}

	public DecorCaptionView(Context context, AttributeSet attrs, int defStyle) {
	super(context, attrs, defStyle);
	init(context);
	}

	private void init(Context context) {
	mDragSlop = ViewConfiguration.get(context).getScaledTouchSlop();
	mGestureDetector = new GestureDetector(context, this);
	}

	@Override
	protected void onFinishInflate() {
	super.onFinishInflate();
	mCaption = getChildAt(0);
	}

	public void setPhoneWindow(PhoneWindow owner, boolean show) {
	mOwner = owner;
	mShow = show;
	mOverlayWithAppContent = owner.isOverlayWithDecorCaptionEnabled();
	if (mOverlayWithAppContent) {
	// The caption is covering the content, so we make its background transparent to make
	// the content visible.
	mCaption.setBackgroundColor(Color.TRANSPARENT);
	}
	updateCaptionVisibility();
	// By changing the outline provider to BOUNDS, the window can remove its
	// background without removing the shadow.
	mOwner.getDecorView().setOutlineProvider(ViewOutlineProvider.BOUNDS);
	mMaximize = findViewById(R.id.maximize_window);
	mClose = findViewById(R.id.close_window);
	}

	@Override
	public boolean onInterceptTouchEvent(MotionEvent ev) {
	// If the user starts touch on the maximize/close buttons, we immediately intercept, so
	// that these buttons are always clickable.
	if (ev.getAction() == MotionEvent.ACTION_DOWN) {
	final int x = (int) ev.getX();
	final int y = (int) ev.getY();
	if (mMaximizeRect.contains(x, y)) {
	mClickTarget = mMaximize;
	}
	if (mCloseRect.contains(x, y)) {
	mClickTarget = mClose;
	}
	}
	return mClickTarget != null;
	}

	@Override
	public boolean onTouchEvent(MotionEvent event) {
	if (mClickTarget != null) {
	mGestureDetector.onTouchEvent(event);
	final int action = event.getAction();
	if (action == MotionEvent.ACTION_UP \|\| action == MotionEvent.ACTION_CANCEL) {
	mClickTarget = null;
	}
	return true;
	}
	return false;
	}

	@Override
	public boolean onTouch(View v, MotionEvent e) {
	// Note: There are no mixed events. When a new device gets used (e.g. 1. Mouse, 2. touch)
	// the old input device events get cancelled first. So no need to remember the kind of
	// input device we are listening to.
	final int x = (int) e.getX();
	final int y = (int) e.getY();
	switch (e.getActionMasked()) {
	case MotionEvent.ACTION_DOWN:
	if (!mShow) {
	// When there is no caption we should not react to anything.
	return false;
	}
	// Checking for a drag action is started if we aren't dragging already and the
	// starting event is either a left mouse button or any other input device.
	if (((e.getToolType(e.getActionIndex()) != MotionEvent.TOOL_TYPE_MOUSE \|\|
	(e.getButtonState() & MotionEvent.BUTTON_PRIMARY) != 0))) {
	mCheckForDragging = true;
	mTouchDownX = x;
	mTouchDownY = y;
	}
	break;

	case MotionEvent.ACTION_MOVE:
	if (!mDragging && mCheckForDragging && passedSlop(x, y)) {
	mCheckForDragging = false;
	mDragging = true;
	mLeftMouseButtonReleased = false;
	startMovingTask(e.getRawX(), e.getRawY());
	} else if (mDragging && !mLeftMouseButtonReleased) {
	if (e.getToolType(e.getActionIndex()) == MotionEvent.TOOL_TYPE_MOUSE &&
	(e.getButtonState() & MotionEvent.BUTTON_PRIMARY) == 0) {
	// There is no separate mouse button up call and if the user mixes mouse
	// button drag actions, we stop dragging once he releases the button.
	mLeftMouseButtonReleased = true;
	break;
	}
	}
	break;

	case MotionEvent.ACTION_UP:
	case MotionEvent.ACTION_CANCEL:
	if (!mDragging) {
	break;
	}
	// Abort the ongoing dragging.
	mDragging = false;
	return !mCheckForDragging;
	}
	return mDragging \|\| mCheckForDragging;
	}

	@Override
	public ArrayList<View> buildTouchDispatchChildList() {
	mTouchDispatchList.ensureCapacity(3);
	if (mCaption != null) {
	mTouchDispatchList.add(mCaption);
	}
	if (mContent != null) {
	mTouchDispatchList.add(mContent);
	}
	return mTouchDispatchList;
	}

	@Override
	public boolean shouldDelayChildPressedState() {
	return false;
	}

	private boolean passedSlop(int x, int y) {
	return Math.abs(x - mTouchDownX) > mDragSlop \|\| Math.abs(y - mTouchDownY) > mDragSlop;
	}

	/**
	* The phone window configuration has changed and the caption needs to be updated.
	* @param show True if the caption should be shown.
	*/
	public void onConfigurationChanged(boolean show) {
	mShow = show;
	updateCaptionVisibility();
	}

	@Override
	public void addView(View child, int index, ViewGroup.LayoutParams params) {
	if (!(params instanceof MarginLayoutParams)) {
	throw new IllegalArgumentException(
	"params " + params + " must subclass MarginLayoutParams");
	}
	// Make sure that we never get more then one client area in our view.
	if (index >= 2 \|\| getChildCount() >= 2) {
	throw new IllegalStateException("DecorCaptionView can only handle 1 client view");
	}
	// To support the overlaying content in the caption, we need to put the content view as the
	// first child to get the right Z-Ordering.
	super.addView(child, 0, params);
	mContent = child;
	}

	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
	final int captionHeight;
	if (mCaption.getVisibility() != View.GONE) {
	measureChildWithMargins(mCaption, widthMeasureSpec, 0, heightMeasureSpec, 0);
	captionHeight = mCaption.getMeasuredHeight();
	} else {
	captionHeight = 0;
	}
	if (mContent != null) {
	if (mOverlayWithAppContent) {
	measureChildWithMargins(mContent, widthMeasureSpec, 0, heightMeasureSpec, 0);
	} else {
	measureChildWithMargins(mContent, widthMeasureSpec, 0, heightMeasureSpec,
	captionHeight);
	}
	}

	setMeasuredDimension(MeasureSpec.getSize(widthMeasureSpec),
	MeasureSpec.getSize(heightMeasureSpec));
	}

	@Override
	protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
	final int captionHeight;
	if (mCaption.getVisibility() != View.GONE) {
	mCaption.layout(0, 0, mCaption.getMeasuredWidth(), mCaption.getMeasuredHeight());
	captionHeight = mCaption.getBottom() - mCaption.getTop();
	mMaximize.getHitRect(mMaximizeRect);
	mClose.getHitRect(mCloseRect);
	} else {
	captionHeight = 0;
	mMaximizeRect.setEmpty();
	mCloseRect.setEmpty();
	}

	if (mContent != null) {
	if (mOverlayWithAppContent) {
	mContent.layout(0, 0, mContent.getMeasuredWidth(), mContent.getMeasuredHeight());
	} else {
	mContent.layout(0, captionHeight, mContent.getMeasuredWidth(),
	captionHeight + mContent.getMeasuredHeight());
	}
	}

	// This assumes that the caption bar is at the top.
	mOwner.notifyRestrictedCaptionAreaCallback(mMaximize.getLeft(), mMaximize.getTop(),
	mClose.getRight(), mClose.getBottom());
	}
	/**
	* Determine if the workspace is entirely covered by the window.
	* @return Returns true when the window is filling the entire screen/workspace.
	**/
	private boolean isFillingScreen() {
	return (0 != ((getWindowSystemUiVisibility() \| getSystemUiVisibility()) &
	(View.SYSTEM_UI_FLAG_FULLSCREEN \| View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION \|
	View.SYSTEM_UI_FLAG_IMMERSIVE \| View.SYSTEM_UI_FLAG_LOW_PROFILE)));
	}

	/**
	* Updates the visibility of the caption.
	**/
	private void updateCaptionVisibility() {
	// Don't show the caption if the window has e.g. entered full screen.
	boolean invisible = isFillingScreen() \|\| !mShow;
	mCaption.setVisibility(invisible ? GONE : VISIBLE);
	mCaption.setOnTouchListener(this);
	}

	/**
	* Maximize the window by moving it to the maximized workspace stack.
	**/
	private void maximizeWindow() {
	Window.WindowControllerCallback callback = mOwner.getWindowControllerCallback();
	if (callback != null) {
	try {
	callback.exitFreeformMode();
	} catch (RemoteException ex) {
	Log.e(TAG, "Cannot change task workspace.");
	}
	}
	}

	public boolean isCaptionShowing() {
	return mShow;
	}

	public int getCaptionHeight() {
	return (mCaption != null) ? mCaption.getHeight() : 0;
	}

	public void removeContentView() {
	if (mContent != null) {
	removeView(mContent);
	mContent = null;
	}
	}

	public View getCaption() {
	return mCaption;
	}

	@Override
	public LayoutParams generateLayoutParams(AttributeSet attrs) {
	return new MarginLayoutParams(getContext(), attrs);
	}

	@Override
	protected LayoutParams generateDefaultLayoutParams() {
	return new MarginLayoutParams(MarginLayoutParams.MATCH_PARENT,
	MarginLayoutParams.MATCH_PARENT);
	}

	@Override
	protected LayoutParams generateLayoutParams(LayoutParams p) {
	return new MarginLayoutParams(p);
	}

	@Override
	protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
	return p instanceof MarginLayoutParams;
	}

	@Override
	public boolean onDown(MotionEvent e) {
	return false;
	}

	@Override
	public void onShowPress(MotionEvent e) {

	}

	@Override
	public boolean onSingleTapUp(MotionEvent e) {
	if (mClickTarget == mMaximize) {
	maximizeWindow();
	} else if (mClickTarget == mClose) {
	mOwner.dispatchOnWindowDismissed(true /finishTask/);
	}
	return true;
	}

	@Override
	public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
	return false;
	}

	@Override
	public void onLongPress(MotionEvent e) {

	}

	@Override
	public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
	return false;
	}
	}