1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.camera.tinyplanet;
18 
19 import android.content.Context;
20 import android.graphics.Bitmap;
21 import android.graphics.Canvas;
22 import android.graphics.Paint;
23 import android.util.AttributeSet;
24 import android.view.View;
25 
26 import java.util.concurrent.locks.Lock;
27 
28 /**
29  * Shows a preview of the TinyPlanet on the screen while editing.
30  */
31 public class TinyPlanetPreview extends View {
32     /**
33      * Classes implementing this interface get informed about changes to the
34      * preview size.
35      */
36     public static interface PreviewSizeListener {
37         /**
38          * Called when the preview size has changed.
39          *
40          * @param sizePx the size in pixels of the square preview area
41          */
onSizeChanged(int sizePx)42         public void onSizeChanged(int sizePx);
43     }
44 
45     private Paint mPaint = new Paint();
46     private Bitmap mPreview;
47     private Lock mLock;
48     private PreviewSizeListener mPreviewSizeListener;
49     private int mSize = 0;
50 
TinyPlanetPreview(Context context)51     public TinyPlanetPreview(Context context) {
52         super(context);
53     }
54 
TinyPlanetPreview(Context context, AttributeSet attrs)55     public TinyPlanetPreview(Context context, AttributeSet attrs) {
56         super(context, attrs);
57     }
58 
TinyPlanetPreview(Context context, AttributeSet attrs, int defStyle)59     public TinyPlanetPreview(Context context, AttributeSet attrs, int defStyle) {
60         super(context, attrs, defStyle);
61     }
62 
63     /**
64      * Sets the bitmap and waits for a draw to happen before returning.
65      */
setBitmap(Bitmap preview, Lock lock)66     public void setBitmap(Bitmap preview, Lock lock) {
67         mPreview = preview;
68         mLock = lock;
69         invalidate();
70     }
71 
setPreviewSizeChangeListener(PreviewSizeListener listener)72     public void setPreviewSizeChangeListener(PreviewSizeListener listener) {
73         mPreviewSizeListener = listener;
74         if (mSize > 0) {
75             mPreviewSizeListener.onSizeChanged(mSize);
76         }
77     }
78 
79     @Override
onDraw(Canvas canvas)80     protected void onDraw(Canvas canvas) {
81         super.onDraw(canvas);
82         if (mLock != null && mLock.tryLock()) {
83             try {
84                 if (mPreview != null && !mPreview.isRecycled()) {
85                     canvas.drawBitmap(mPreview, 0, 0, mPaint);
86                 }
87             } finally {
88                 mLock.unlock();
89             }
90         }
91     }
92 
93     @Override
onMeasure(int widthMeasureSpec, int heightMeasureSpec)94     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
95         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
96 
97         // Make sure the view is square
98         int size = Math.min(getMeasuredWidth(), getMeasuredHeight());
99         setMeasuredDimension(size, size);
100     }
101 
102     @Override
onLayout(boolean changed, int left, int top, int right, int bottom)103     protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
104         super.onLayout(changed, left, top, right, bottom);
105         if (changed && mPreviewSizeListener != null) {
106             int width = right - left;
107             int height = bottom - top;
108 
109             // These should be the same as we enforce a square layout, but let's
110             // be safe.
111             int mSize = Math.min(width, height);
112 
113             // Tell the listener about our new size so the renderer can adapt.
114             if (mSize > 0 && mPreviewSizeListener != null) {
115                 mPreviewSizeListener.onSizeChanged(mSize);
116             }
117         }
118     }
119 }
120