packages/PrintSpooler/src/com/android/printspooler/widget/ContentView.java - platform/frameworks/base - Gitiles

 /*
  * Copyright (C) 2014 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.printspooler.widget;

 import android.content.Context;
 import android.support.v4.widget.ViewDragHelper;
 import android.util.AttributeSet;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewGroup;
 import com.android.printspooler.R;

 /**
  * This class is a layout manager for the print screen. It has a sliding
  * area that contains the print options. If the sliding area is open the
  * print options are visible and if it is closed a summary of the print
  * job is shown. Under the sliding area there is a place for putting
  * arbitrary content such as preview, error message, progress indicator,
  * etc. The sliding area is covering the content holder under it when
  * the former is opened.
  */
 @SuppressWarnings("unused")
 public final class ContentView extends ViewGroup implements View.OnClickListener {
     private static final int FIRST_POINTER_ID = 0;

     private final ViewDragHelper mDragger;

     private View mStaticContent;
     private ViewGroup mSummaryContent;
     private View mDynamicContent;

     private View mDraggableContent;
     private ViewGroup mMoreOptionsContainer;
     private ViewGroup mOptionsContainer;

     private View mEmbeddedContentContainer;

     private View mExpandCollapseHandle;
     private View mExpandCollapseIcon;

     private int mClosedOptionsOffsetY;
     private int mCurrentOptionsOffsetY;

     private OptionsStateChangeListener mOptionsStateChangeListener;

     private int mOldDraggableHeight;

     public interface OptionsStateChangeListener {
         public void onOptionsOpened();
         public void onOptionsClosed();
     }

     public ContentView(Context context, AttributeSet attrs) {
         super(context, attrs);
         mDragger = ViewDragHelper.create(this, new DragCallbacks());

         // The options view is sliding under the static header but appears
         // after it in the layout, so we will draw in opposite order.
         setChildrenDrawingOrderEnabled(true);
     }

     public void setOptionsStateChangeListener(OptionsStateChangeListener listener) {
         mOptionsStateChangeListener = listener;
     }

     private boolean isOptionsOpened() {
         return mCurrentOptionsOffsetY == 0;
     }

     private boolean isOptionsClosed() {
         return mCurrentOptionsOffsetY == mClosedOptionsOffsetY;
     }

     private void openOptions() {
         if (isOptionsOpened()) {
             return;
         }
         mDragger.smoothSlideViewTo(mDynamicContent, mDynamicContent.getLeft(),
                 getOpenedOptionsY());
         invalidate();
     }

     private void closeOptions() {
         if (isOptionsClosed()) {
             return;
         }
         mDragger.smoothSlideViewTo(mDynamicContent, mDynamicContent.getLeft(),
                 getClosedOptionsY());
         invalidate();
     }

     @Override
     protected int getChildDrawingOrder(int childCount, int i) {
         return childCount - i - 1;
     }

     @Override
     protected void onFinishInflate() {
         mStaticContent = findViewById(R.id.static_content);
         mSummaryContent = (ViewGroup) findViewById(R.id.summary_content);
         mDynamicContent = findViewById(R.id.dynamic_content);
         mDraggableContent = findViewById(R.id.draggable_content);
         mMoreOptionsContainer = (ViewGroup) findViewById(R.id.more_options_container);
         mOptionsContainer = (ViewGroup) findViewById(R.id.options_container);
         mEmbeddedContentContainer = findViewById(R.id.embedded_content_container);
         mExpandCollapseIcon = findViewById(R.id.expand_collapse_icon);
         mExpandCollapseHandle = findViewById(R.id.expand_collapse_handle);

         mExpandCollapseIcon.setOnClickListener(this);
         mExpandCollapseHandle.setOnClickListener(this);

         // Make sure we start in a closed options state.
         onDragProgress(1.0f);
     }

     @Override
     public void onClick(View view) {
         if (view == mExpandCollapseHandle || view == mExpandCollapseIcon) {
             if (isOptionsClosed()) {
                 openOptions();
             } else if (isOptionsOpened()) {
                 closeOptions();
             } // else in open/close progress do nothing.
         }
     }

     @Override
     public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) {
         /* do nothing */
     }

     @Override
     public boolean onTouchEvent(MotionEvent event) {
         mDragger.processTouchEvent(event);
         return true;
     }

     @Override
     public boolean onInterceptTouchEvent(MotionEvent event) {
         return mDragger.shouldInterceptTouchEvent(event)
                 || super.onInterceptTouchEvent(event);
     }

     @Override
     public void computeScroll() {
         if (mDragger.continueSettling(true)) {
             postInvalidateOnAnimation();
         }
     }

     private int getOpenedOptionsY() {
         return mStaticContent.getBottom();
     }

     private int getClosedOptionsY() {
         return getOpenedOptionsY() + mClosedOptionsOffsetY;
     }

     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         measureChild(mStaticContent, widthMeasureSpec, heightMeasureSpec);

         if (mSummaryContent.getVisibility() != View.GONE) {
             measureChild(mSummaryContent, widthMeasureSpec, heightMeasureSpec);
         }

         measureChild(mDynamicContent, widthMeasureSpec, heightMeasureSpec);

         final int heightSize = MeasureSpec.getSize(heightMeasureSpec);

 //        // The height of the draggable content may change and if that happens
 //        // we have to adjust the current offset to ensure the sliding area is
 //        // at the same position.
 //        mCurrentOptionsOffsetY -= mDraggableContent.getMeasuredHeight()
 //                - oldDraggableHeight;

         if (mOldDraggableHeight != mDraggableContent.getMeasuredHeight()) {
             mCurrentOptionsOffsetY -= mDraggableContent.getMeasuredHeight()
                     - mOldDraggableHeight;
             mOldDraggableHeight = mDraggableContent.getMeasuredHeight();
         }

         // The height of the draggable content may change and if that happens
         // we have to adjust the sliding area closed state offset.
         mClosedOptionsOffsetY = mSummaryContent.getMeasuredHeight()
                 - mDraggableContent.getMeasuredHeight();

         // The content host must be maximally large size that fits entirely
         // on the screen when the options are collapsed.
         ViewGroup.LayoutParams params = mEmbeddedContentContainer.getLayoutParams();
         if (params.height == 0) {
             params.height = heightSize - mStaticContent.getMeasuredHeight()
                     - mSummaryContent.getMeasuredHeight() - mDynamicContent.getMeasuredHeight()
                     + mDraggableContent.getMeasuredHeight();

             mCurrentOptionsOffsetY = mClosedOptionsOffsetY;
         }

         // The content host can grow vertically as much as needed - we will be covering it.
         final int hostHeightMeasureSpec = MeasureSpec.makeMeasureSpec(MeasureSpec.UNSPECIFIED, 0);
         measureChild(mEmbeddedContentContainer, widthMeasureSpec, hostHeightMeasureSpec);

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

     @Override
     protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
         mStaticContent.layout(left, top, right, mStaticContent.getMeasuredHeight());

         if (mSummaryContent.getVisibility() != View.GONE) {
             mSummaryContent.layout(left, mStaticContent.getMeasuredHeight(), right,
                     mStaticContent.getMeasuredHeight() + mSummaryContent.getMeasuredHeight());
         }

         final int dynContentTop = mStaticContent.getMeasuredHeight() + mCurrentOptionsOffsetY;
         final int dynContentBottom = dynContentTop + mDynamicContent.getMeasuredHeight();

         mDynamicContent.layout(left, dynContentTop, right, dynContentBottom);

         final int embContentTop = mStaticContent.getMeasuredHeight() + mClosedOptionsOffsetY
                 + mDynamicContent.getMeasuredHeight();
         final int embContentBottom = embContentTop + mEmbeddedContentContainer.getMeasuredHeight();

         mEmbeddedContentContainer.layout(left, embContentTop, right, embContentBottom);
     }

     private void onDragProgress(float progress) {
         final int summaryCount = mSummaryContent.getChildCount();
         for (int i = 0; i < summaryCount; i++) {
             View child = mSummaryContent.getChildAt(i);
             child.setAlpha(progress);
         }

         if (progress == 0) {
             if (mOptionsStateChangeListener != null) {
                 mOptionsStateChangeListener.onOptionsOpened();
             }
             mSummaryContent.setVisibility(View.GONE);
             mExpandCollapseIcon.setBackgroundResource(R.drawable.ic_expand_less);
         } else {
             mSummaryContent.setVisibility(View.VISIBLE);
         }

         final float inverseAlpha = 1.0f - progress;

         final int optionCount = mOptionsContainer.getChildCount();
         for (int i = 0; i < optionCount; i++) {
             View child = mOptionsContainer.getChildAt(i);
             child.setAlpha(inverseAlpha);
         }

         if (mMoreOptionsContainer.getVisibility() != View.GONE) {
             final int moreOptionCount = mMoreOptionsContainer.getChildCount();
             for (int i = 0; i < moreOptionCount; i++) {
                 View child = mMoreOptionsContainer.getChildAt(i);
                 child.setAlpha(inverseAlpha);
             }
         }

         if (inverseAlpha == 0) {
             if (mOptionsStateChangeListener != null) {
                 mOptionsStateChangeListener.onOptionsClosed();
             }
             if (mMoreOptionsContainer.getVisibility() != View.GONE) {
                 mMoreOptionsContainer.setVisibility(View.INVISIBLE);
             }
             mDraggableContent.setVisibility(View.INVISIBLE);
             mExpandCollapseIcon.setBackgroundResource(R.drawable.ic_expand_more);
         } else {
             if (mMoreOptionsContainer.getVisibility() != View.GONE) {
                 mMoreOptionsContainer.setVisibility(View.VISIBLE);
             }
             mDraggableContent.setVisibility(View.VISIBLE);
         }
     }

     private final class DragCallbacks extends ViewDragHelper.Callback {
         @Override
         public boolean tryCaptureView(View child, int pointerId) {
             return child == mDynamicContent && pointerId == FIRST_POINTER_ID;
         }

         @Override
         public void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) {
             mCurrentOptionsOffsetY += dy;
             final float progress = ((float) top - getOpenedOptionsY())
                     / (getClosedOptionsY() - getOpenedOptionsY());

             mDraggableContent.notifySubtreeAccessibilityStateChangedIfNeeded();

             onDragProgress(progress);
         }

         public void onViewReleased(View child, float velocityX, float velocityY) {
             final int childTop = child.getTop();

             final int openedOptionsY = getOpenedOptionsY();
             final int closedOptionsY = getClosedOptionsY();

             if (childTop == openedOptionsY || childTop == closedOptionsY) {
                 return;
             }

             final int halfRange = closedOptionsY + (openedOptionsY - closedOptionsY) / 2;
             if (childTop < halfRange) {
                 mDragger.smoothSlideViewTo(child, child.getLeft(), closedOptionsY);
             } else {
                 mDragger.smoothSlideViewTo(child, child.getLeft(), openedOptionsY);
             }

             invalidate();
         }

         public int getViewVerticalDragRange(View child) {
             return mDraggableContent.getHeight();
         }

         public int clampViewPositionVertical(View child, int top, int dy) {
             final int staticOptionBottom = mStaticContent.getBottom();
             return Math.max(Math.min(top, getOpenedOptionsY()), getClosedOptionsY());
         }
     }
 }
	/*
	* Copyright (C) 2014 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.printspooler.widget;

	import android.content.Context;
	import android.support.v4.widget.ViewDragHelper;
	import android.util.AttributeSet;
	import android.view.MotionEvent;
	import android.view.View;
	import android.view.ViewGroup;
	import com.android.printspooler.R;

	/**
	* This class is a layout manager for the print screen. It has a sliding
	* area that contains the print options. If the sliding area is open the
	* print options are visible and if it is closed a summary of the print
	* job is shown. Under the sliding area there is a place for putting
	* arbitrary content such as preview, error message, progress indicator,
	* etc. The sliding area is covering the content holder under it when
	* the former is opened.
	*/
	@SuppressWarnings("unused")
	public final class ContentView extends ViewGroup implements View.OnClickListener {
	private static final int FIRST_POINTER_ID = 0;

	private final ViewDragHelper mDragger;

	private View mStaticContent;
	private ViewGroup mSummaryContent;
	private View mDynamicContent;

	private View mDraggableContent;
	private ViewGroup mMoreOptionsContainer;
	private ViewGroup mOptionsContainer;

	private View mEmbeddedContentContainer;

	private View mExpandCollapseHandle;
	private View mExpandCollapseIcon;

	private int mClosedOptionsOffsetY;
	private int mCurrentOptionsOffsetY;

	private OptionsStateChangeListener mOptionsStateChangeListener;

	private int mOldDraggableHeight;

	public interface OptionsStateChangeListener {
	public void onOptionsOpened();
	public void onOptionsClosed();
	}

	public ContentView(Context context, AttributeSet attrs) {
	super(context, attrs);
	mDragger = ViewDragHelper.create(this, new DragCallbacks());

	// The options view is sliding under the static header but appears
	// after it in the layout, so we will draw in opposite order.
	setChildrenDrawingOrderEnabled(true);
	}

	public void setOptionsStateChangeListener(OptionsStateChangeListener listener) {
	mOptionsStateChangeListener = listener;
	}

	private boolean isOptionsOpened() {
	return mCurrentOptionsOffsetY == 0;
	}

	private boolean isOptionsClosed() {
	return mCurrentOptionsOffsetY == mClosedOptionsOffsetY;
	}

	private void openOptions() {
	if (isOptionsOpened()) {
	return;
	}
	mDragger.smoothSlideViewTo(mDynamicContent, mDynamicContent.getLeft(),
	getOpenedOptionsY());
	invalidate();
	}

	private void closeOptions() {
	if (isOptionsClosed()) {
	return;
	}
	mDragger.smoothSlideViewTo(mDynamicContent, mDynamicContent.getLeft(),
	getClosedOptionsY());
	invalidate();
	}

	@Override
	protected int getChildDrawingOrder(int childCount, int i) {
	return childCount - i - 1;
	}

	@Override
	protected void onFinishInflate() {
	mStaticContent = findViewById(R.id.static_content);
	mSummaryContent = (ViewGroup) findViewById(R.id.summary_content);
	mDynamicContent = findViewById(R.id.dynamic_content);
	mDraggableContent = findViewById(R.id.draggable_content);
	mMoreOptionsContainer = (ViewGroup) findViewById(R.id.more_options_container);
	mOptionsContainer = (ViewGroup) findViewById(R.id.options_container);
	mEmbeddedContentContainer = findViewById(R.id.embedded_content_container);
	mExpandCollapseIcon = findViewById(R.id.expand_collapse_icon);
	mExpandCollapseHandle = findViewById(R.id.expand_collapse_handle);

	mExpandCollapseIcon.setOnClickListener(this);
	mExpandCollapseHandle.setOnClickListener(this);

	// Make sure we start in a closed options state.
	onDragProgress(1.0f);
	}

	@Override
	public void onClick(View view) {
	if (view == mExpandCollapseHandle \|\| view == mExpandCollapseIcon) {
	if (isOptionsClosed()) {
	openOptions();
	} else if (isOptionsOpened()) {
	closeOptions();
	} // else in open/close progress do nothing.
	}
	}

	@Override
	public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) {
	/* do nothing */
	}

	@Override
	public boolean onTouchEvent(MotionEvent event) {
	mDragger.processTouchEvent(event);
	return true;
	}

	@Override
	public boolean onInterceptTouchEvent(MotionEvent event) {
	return mDragger.shouldInterceptTouchEvent(event)
	\|\| super.onInterceptTouchEvent(event);
	}

	@Override
	public void computeScroll() {
	if (mDragger.continueSettling(true)) {
	postInvalidateOnAnimation();
	}
	}

	private int getOpenedOptionsY() {
	return mStaticContent.getBottom();
	}

	private int getClosedOptionsY() {
	return getOpenedOptionsY() + mClosedOptionsOffsetY;
	}

	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
	measureChild(mStaticContent, widthMeasureSpec, heightMeasureSpec);

	if (mSummaryContent.getVisibility() != View.GONE) {
	measureChild(mSummaryContent, widthMeasureSpec, heightMeasureSpec);
	}

	measureChild(mDynamicContent, widthMeasureSpec, heightMeasureSpec);

	final int heightSize = MeasureSpec.getSize(heightMeasureSpec);

	// // The height of the draggable content may change and if that happens
	// // we have to adjust the current offset to ensure the sliding area is
	// // at the same position.
	// mCurrentOptionsOffsetY -= mDraggableContent.getMeasuredHeight()
	// - oldDraggableHeight;

	if (mOldDraggableHeight != mDraggableContent.getMeasuredHeight()) {
	mCurrentOptionsOffsetY -= mDraggableContent.getMeasuredHeight()
	- mOldDraggableHeight;
	mOldDraggableHeight = mDraggableContent.getMeasuredHeight();
	}

	// The height of the draggable content may change and if that happens
	// we have to adjust the sliding area closed state offset.
	mClosedOptionsOffsetY = mSummaryContent.getMeasuredHeight()
	- mDraggableContent.getMeasuredHeight();

	// The content host must be maximally large size that fits entirely
	// on the screen when the options are collapsed.
	ViewGroup.LayoutParams params = mEmbeddedContentContainer.getLayoutParams();
	if (params.height == 0) {
	params.height = heightSize - mStaticContent.getMeasuredHeight()
	- mSummaryContent.getMeasuredHeight() - mDynamicContent.getMeasuredHeight()
	+ mDraggableContent.getMeasuredHeight();

	mCurrentOptionsOffsetY = mClosedOptionsOffsetY;
	}

	// The content host can grow vertically as much as needed - we will be covering it.
	final int hostHeightMeasureSpec = MeasureSpec.makeMeasureSpec(MeasureSpec.UNSPECIFIED, 0);
	measureChild(mEmbeddedContentContainer, widthMeasureSpec, hostHeightMeasureSpec);

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

	@Override
	protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
	mStaticContent.layout(left, top, right, mStaticContent.getMeasuredHeight());

	if (mSummaryContent.getVisibility() != View.GONE) {
	mSummaryContent.layout(left, mStaticContent.getMeasuredHeight(), right,
	mStaticContent.getMeasuredHeight() + mSummaryContent.getMeasuredHeight());
	}

	final int dynContentTop = mStaticContent.getMeasuredHeight() + mCurrentOptionsOffsetY;
	final int dynContentBottom = dynContentTop + mDynamicContent.getMeasuredHeight();

	mDynamicContent.layout(left, dynContentTop, right, dynContentBottom);

	final int embContentTop = mStaticContent.getMeasuredHeight() + mClosedOptionsOffsetY
	+ mDynamicContent.getMeasuredHeight();
	final int embContentBottom = embContentTop + mEmbeddedContentContainer.getMeasuredHeight();

	mEmbeddedContentContainer.layout(left, embContentTop, right, embContentBottom);
	}

	private void onDragProgress(float progress) {
	final int summaryCount = mSummaryContent.getChildCount();
	for (int i = 0; i < summaryCount; i++) {
	View child = mSummaryContent.getChildAt(i);
	child.setAlpha(progress);
	}

	if (progress == 0) {
	if (mOptionsStateChangeListener != null) {
	mOptionsStateChangeListener.onOptionsOpened();
	}
	mSummaryContent.setVisibility(View.GONE);
	mExpandCollapseIcon.setBackgroundResource(R.drawable.ic_expand_less);
	} else {
	mSummaryContent.setVisibility(View.VISIBLE);
	}

	final float inverseAlpha = 1.0f - progress;

	final int optionCount = mOptionsContainer.getChildCount();
	for (int i = 0; i < optionCount; i++) {
	View child = mOptionsContainer.getChildAt(i);
	child.setAlpha(inverseAlpha);
	}

	if (mMoreOptionsContainer.getVisibility() != View.GONE) {
	final int moreOptionCount = mMoreOptionsContainer.getChildCount();
	for (int i = 0; i < moreOptionCount; i++) {
	View child = mMoreOptionsContainer.getChildAt(i);
	child.setAlpha(inverseAlpha);
	}
	}

	if (inverseAlpha == 0) {
	if (mOptionsStateChangeListener != null) {
	mOptionsStateChangeListener.onOptionsClosed();
	}
	if (mMoreOptionsContainer.getVisibility() != View.GONE) {
	mMoreOptionsContainer.setVisibility(View.INVISIBLE);
	}
	mDraggableContent.setVisibility(View.INVISIBLE);
	mExpandCollapseIcon.setBackgroundResource(R.drawable.ic_expand_more);
	} else {
	if (mMoreOptionsContainer.getVisibility() != View.GONE) {
	mMoreOptionsContainer.setVisibility(View.VISIBLE);
	}
	mDraggableContent.setVisibility(View.VISIBLE);
	}
	}

	private final class DragCallbacks extends ViewDragHelper.Callback {
	@Override
	public boolean tryCaptureView(View child, int pointerId) {
	return child == mDynamicContent && pointerId == FIRST_POINTER_ID;
	}

	@Override
	public void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) {
	mCurrentOptionsOffsetY += dy;
	final float progress = ((float) top - getOpenedOptionsY())
	/ (getClosedOptionsY() - getOpenedOptionsY());

	mDraggableContent.notifySubtreeAccessibilityStateChangedIfNeeded();

	onDragProgress(progress);
	}

	public void onViewReleased(View child, float velocityX, float velocityY) {
	final int childTop = child.getTop();

	final int openedOptionsY = getOpenedOptionsY();
	final int closedOptionsY = getClosedOptionsY();

	if (childTop == openedOptionsY \|\| childTop == closedOptionsY) {
	return;
	}

	final int halfRange = closedOptionsY + (openedOptionsY - closedOptionsY) / 2;
	if (childTop < halfRange) {
	mDragger.smoothSlideViewTo(child, child.getLeft(), closedOptionsY);
	} else {
	mDragger.smoothSlideViewTo(child, child.getLeft(), openedOptionsY);
	}

	invalidate();
	}

	public int getViewVerticalDragRange(View child) {
	return mDraggableContent.getHeight();
	}

	public int clampViewPositionVertical(View child, int top, int dy) {
	final int staticOptionBottom = mStaticContent.getBottom();
	return Math.max(Math.min(top, getOpenedOptionsY()), getClosedOptionsY());
	}
	}
	}