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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 com.example.android.apis.R;
     20 
     21 import android.app.Activity;
     22 import android.content.Context;
     23 import android.graphics.*;
     24 import android.os.Bundle;
     25 import android.view.KeyEvent;
     26 import android.view.*;
     27 
     28 import java.io.ByteArrayOutputStream;
     29 
     30 public class CreateBitmap extends GraphicsActivity {
     31 
     32     @Override
     33     protected void onCreate(Bundle savedInstanceState) {
     34         super.onCreate(savedInstanceState);
     35         setContentView(new SampleView(this));
     36     }
     37 
     38     private static final int WIDTH = 50;
     39     private static final int HEIGHT = 50;
     40     private static final int STRIDE = 64;   // must be >= WIDTH
     41 
     42     private static int[] createColors() {
     43         int[] colors = new int[STRIDE * HEIGHT];
     44         for (int y = 0; y < HEIGHT; y++) {
     45             for (int x = 0; x < WIDTH; x++) {
     46                 int r = x * 255 / (WIDTH - 1);
     47                 int g = y * 255 / (HEIGHT - 1);
     48                 int b = 255 - Math.min(r, g);
     49                 int a = Math.max(r, g);
     50                 colors[y * STRIDE + x] = (a << 24) | (r << 16) | (g << 8) | b;
     51             }
     52         }
     53         return colors;
     54     }
     55 
     56     private static class SampleView extends View {
     57         private Bitmap[] mBitmaps;
     58         private Bitmap[] mJPEG;
     59         private Bitmap[] mPNG;
     60         private int[]    mColors;
     61         private Paint    mPaint;
     62 
     63         private static Bitmap codec(Bitmap src, Bitmap.CompressFormat format,
     64                                     int quality) {
     65             ByteArrayOutputStream os = new ByteArrayOutputStream();
     66             src.compress(format, quality, os);
     67 
     68             byte[] array = os.toByteArray();
     69             return BitmapFactory.decodeByteArray(array, 0, array.length);
     70         }
     71 
     72         public SampleView(Context context) {
     73             super(context);
     74             setFocusable(true);
     75 
     76             mColors = createColors();
     77             int[] colors = mColors;
     78 
     79             mBitmaps = new Bitmap[6];
     80             // these three are initialized with colors[]
     81             mBitmaps[0] = Bitmap.createBitmap(colors, 0, STRIDE, WIDTH, HEIGHT,
     82                                               Bitmap.Config.ARGB_8888);
     83             mBitmaps[1] = Bitmap.createBitmap(colors, 0, STRIDE, WIDTH, HEIGHT,
     84                                               Bitmap.Config.RGB_565);
     85             mBitmaps[2] = Bitmap.createBitmap(colors, 0, STRIDE, WIDTH, HEIGHT,
     86                                               Bitmap.Config.ARGB_4444);
     87 
     88             // these three will have their colors set later
     89             mBitmaps[3] = Bitmap.createBitmap(WIDTH, HEIGHT,
     90                                               Bitmap.Config.ARGB_8888);
     91             mBitmaps[4] = Bitmap.createBitmap(WIDTH, HEIGHT,
     92                                               Bitmap.Config.RGB_565);
     93             mBitmaps[5] = Bitmap.createBitmap(WIDTH, HEIGHT,
     94                                               Bitmap.Config.ARGB_4444);
     95             for (int i = 3; i <= 5; i++) {
     96                 mBitmaps[i].setPixels(colors, 0, STRIDE, 0, 0, WIDTH, HEIGHT);
     97             }
     98 
     99             mPaint = new Paint();
    100             mPaint.setDither(true);
    101 
    102             // now encode/decode using JPEG and PNG
    103             mJPEG = new Bitmap[mBitmaps.length];
    104             mPNG = new Bitmap[mBitmaps.length];
    105             for (int i = 0; i < mBitmaps.length; i++) {
    106                 mJPEG[i] = codec(mBitmaps[i], Bitmap.CompressFormat.JPEG, 80);
    107                 mPNG[i] = codec(mBitmaps[i], Bitmap.CompressFormat.PNG, 0);
    108             }
    109         }
    110 
    111         @Override protected void onDraw(Canvas canvas) {
    112             canvas.drawColor(Color.WHITE);
    113 
    114             for (int i = 0; i < mBitmaps.length; i++) {
    115                 canvas.drawBitmap(mBitmaps[i], 0, 0, null);
    116                 canvas.drawBitmap(mJPEG[i], 80, 0, null);
    117                 canvas.drawBitmap(mPNG[i], 160, 0, null);
    118                 canvas.translate(0, mBitmaps[i].getHeight());
    119             }
    120 
    121             // draw the color array directly, w/o craeting a bitmap object
    122             canvas.drawBitmap(mColors, 0, STRIDE, 0, 0, WIDTH, HEIGHT,
    123                               true, null);
    124             canvas.translate(0, HEIGHT);
    125             canvas.drawBitmap(mColors, 0, STRIDE, 0, 0, WIDTH, HEIGHT,
    126                               false, mPaint);
    127         }
    128     }
    129 }
    130 
    131