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.example.android.activityanim; 18 19 import java.util.ArrayList; 20 import java.util.HashMap; 21 22 import android.content.Context; 23 import android.content.res.Resources; 24 import android.graphics.Bitmap; 25 import android.graphics.BitmapFactory; 26 import android.graphics.drawable.BitmapDrawable; 27 import android.widget.ImageView; 28 29 public class BitmapUtils { 30 31 int[] mPhotos = { 32 R.drawable.p1, 33 R.drawable.p2, 34 R.drawable.p3, 35 R.drawable.p4 36 }; 37 38 String[] mDescriptions = { 39 "This picture was taken while sunbathing in a natural hot spring, which was " + 40 "unfortunately filled with acid, which is a lasting memory from that trip, whenever I " + 41 "I look at my own skin.", 42 "I took this shot with a pinhole camera mounted on a tripod constructed out of " + 43 "soda straws. I felt that that combination best captured the beauty of the landscape " + 44 "in juxtaposition with the detritus of mankind.", 45 "I don't remember where or when I took this picture. All I know is that I was really " + 46 "drunk at the time, and I woke up without my left sock.", 47 "Right before I took this picture, there was a busload of school children right " + 48 "in my way. I knew the perfect shot was coming, so I quickly yelled 'Free candy!!!' " + 49 "and they scattered.", 50 }; 51 52 static HashMap<Integer, Bitmap> sBitmapResourceMap = new HashMap<Integer, Bitmap>(); 53 54 /** 55 * Load pictures and descriptions. A real app wouldn't do it this way, but that's 56 * not the point of this animation demo. Loading asynchronously is a better way to go 57 * for what can be time-consuming operations. 58 */ loadPhotos(Resources resources)59 public ArrayList<PictureData> loadPhotos(Resources resources) { 60 ArrayList<PictureData> pictures = new ArrayList<PictureData>(); 61 for (int i = 0; i < 30; ++i) { 62 int resourceId = mPhotos[(int) (Math.random() * mPhotos.length)]; 63 Bitmap bitmap = getBitmap(resources, resourceId); 64 Bitmap thumbnail = getThumbnail(bitmap, 200); 65 String description = mDescriptions[(int) (Math.random() * mDescriptions.length)]; 66 pictures.add(new PictureData(resourceId, description, thumbnail)); 67 } 68 return pictures; 69 } 70 71 /** 72 * Utility method to get bitmap from cache or, if not there, load it 73 * from its resource. 74 */ getBitmap(Resources resources, int resourceId)75 static Bitmap getBitmap(Resources resources, int resourceId) { 76 Bitmap bitmap = sBitmapResourceMap.get(resourceId); 77 if (bitmap == null) { 78 bitmap = BitmapFactory.decodeResource(resources, resourceId); 79 sBitmapResourceMap.put(resourceId, bitmap); 80 } 81 return bitmap; 82 } 83 84 /** 85 * Create and return a thumbnail image given the original source bitmap and a max 86 * dimension (width or height). 87 */ getThumbnail(Bitmap original, int maxDimension)88 private Bitmap getThumbnail(Bitmap original, int maxDimension) { 89 int width = original.getWidth(); 90 int height = original.getHeight(); 91 int scaledWidth, scaledHeight; 92 if (width >= height) { 93 float scaleFactor = (float) maxDimension / width; 94 scaledWidth = 200; 95 scaledHeight = (int) (scaleFactor * height); 96 } else { 97 float scaleFactor = (float) maxDimension / height; 98 scaledWidth = (int) (scaleFactor * width); 99 scaledHeight = 200; 100 } 101 Bitmap thumbnail = Bitmap.createScaledBitmap(original, scaledWidth, scaledHeight, true); 102 103 return thumbnail; 104 } 105 106 107 } 108