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1 /*
2  * Copyright (C) 2007 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.example.android.apis.graphics;
18 
19 import android.content.Context;
20 import android.graphics.*;
21 import android.os.Bundle;
22 import android.view.*;
23 
24 import java.io.ByteArrayOutputStream;
25 
26 public class CreateBitmap extends GraphicsActivity {
27 
28     @Override
onCreate(Bundle savedInstanceState)29     protected void onCreate(Bundle savedInstanceState) {
30         super.onCreate(savedInstanceState);
31         setContentView(new SampleView(this));
32     }
33 
34     private static final int WIDTH = 50;
35     private static final int HEIGHT = 50;
36     private static final int STRIDE = 64;   // must be >= WIDTH
37 
createColors()38     private static int[] createColors() {
39         int[] colors = new int[STRIDE * HEIGHT];
40         for (int y = 0; y < HEIGHT; y++) {
41             for (int x = 0; x < WIDTH; x++) {
42                 int r = x * 255 / (WIDTH - 1);
43                 int g = y * 255 / (HEIGHT - 1);
44                 int b = 255 - Math.min(r, g);
45                 int a = Math.max(r, g);
46                 colors[y * STRIDE + x] = (a << 24) | (r << 16) | (g << 8) | b;
47             }
48         }
49         return colors;
50     }
51 
52     private static class SampleView extends View {
53         private Bitmap[] mBitmaps;
54         private Bitmap[] mJPEG;
55         private Bitmap[] mPNG;
56         private int[]    mColors;
57         private Paint    mPaint;
58 
codec(Bitmap src, Bitmap.CompressFormat format, int quality)59         private static Bitmap codec(Bitmap src, Bitmap.CompressFormat format,
60                                     int quality) {
61             ByteArrayOutputStream os = new ByteArrayOutputStream();
62             src.compress(format, quality, os);
63 
64             byte[] array = os.toByteArray();
65             return BitmapFactory.decodeByteArray(array, 0, array.length);
66         }
67 
SampleView(Context context)68         public SampleView(Context context) {
69             super(context);
70             setFocusable(true);
71 
72             mColors = createColors();
73             int[] colors = mColors;
74 
75             mBitmaps = new Bitmap[6];
76             // these three are initialized with colors[]
77             mBitmaps[0] = Bitmap.createBitmap(colors, 0, STRIDE, WIDTH, HEIGHT,
78                                               Bitmap.Config.ARGB_8888);
79             mBitmaps[1] = Bitmap.createBitmap(colors, 0, STRIDE, WIDTH, HEIGHT,
80                                               Bitmap.Config.RGB_565);
81             mBitmaps[2] = Bitmap.createBitmap(colors, 0, STRIDE, WIDTH, HEIGHT,
82                                               Bitmap.Config.ARGB_4444);
83 
84             // these three will have their colors set later
85             mBitmaps[3] = Bitmap.createBitmap(WIDTH, HEIGHT,
86                                               Bitmap.Config.ARGB_8888);
87             mBitmaps[4] = Bitmap.createBitmap(WIDTH, HEIGHT,
88                                               Bitmap.Config.RGB_565);
89             mBitmaps[5] = Bitmap.createBitmap(WIDTH, HEIGHT,
90                                               Bitmap.Config.ARGB_4444);
91             for (int i = 3; i <= 5; i++) {
92                 mBitmaps[i].setPixels(colors, 0, STRIDE, 0, 0, WIDTH, HEIGHT);
93             }
94 
95             mPaint = new Paint();
96             mPaint.setDither(true);
97 
98             // now encode/decode using JPEG and PNG
99             mJPEG = new Bitmap[mBitmaps.length];
100             mPNG = new Bitmap[mBitmaps.length];
101             for (int i = 0; i < mBitmaps.length; i++) {
102                 mJPEG[i] = codec(mBitmaps[i], Bitmap.CompressFormat.JPEG, 80);
103                 mPNG[i] = codec(mBitmaps[i], Bitmap.CompressFormat.PNG, 0);
104             }
105         }
106 
onDraw(Canvas canvas)107         @Override protected void onDraw(Canvas canvas) {
108             canvas.drawColor(Color.WHITE);
109 
110             for (int i = 0; i < mBitmaps.length; i++) {
111                 canvas.drawBitmap(mBitmaps[i], 0, 0, null);
112                 canvas.drawBitmap(mJPEG[i], 80, 0, null);
113                 canvas.drawBitmap(mPNG[i], 160, 0, null);
114                 canvas.translate(0, mBitmaps[i].getHeight());
115             }
116 
117             // draw the color array directly, w/o craeting a bitmap object
118             canvas.drawBitmap(mColors, 0, STRIDE, 0, 0, WIDTH, HEIGHT,
119                               true, null);
120             canvas.translate(0, HEIGHT);
121             canvas.drawBitmap(mColors, 0, STRIDE, 0, 0, WIDTH, HEIGHT,
122                               false, mPaint);
123         }
124     }
125 }
126 
127