1 /*
2  * Copyright (C) 2009 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.app.AlertDialog;
20 import android.content.DialogInterface;
21 import android.content.pm.ActivityInfo;
22 import android.content.pm.PackageManager;
23 import android.content.pm.PackageManager.NameNotFoundException;
24 import android.os.Bundle;
25 import android.os.Handler;
26 import android.os.Message;
27 
28 /**
29  * PurgeableBitmap demonstrates the effects of setting Bitmaps as being
30  * purgeable.
31  *
32  * In the NonPurgeable case, an encoded bitstream is decoded to a different
33  * Bitmap over and over again up to 200 times until out-of-memory occurs.
34  * In contrast, the Purgeable case shows that the system can complete decoding
35  * the encoded bitstream 200 times without hitting the out-of-memory case.
36  */
37 public class PurgeableBitmap extends GraphicsActivity {
38 
39     private PurgeableBitmapView mView;
40     private final RefreshHandler mRedrawHandler = new RefreshHandler();
41 
42     class RefreshHandler extends Handler {
43 
44         @Override
handleMessage(Message msg)45         public void handleMessage(Message msg) {
46             int index = mView.update(this);
47             if (index > 0) {
48                 showAlertDialog(getDialogMessage(true, index));
49             } else if (index < 0){
50                 mView.invalidate();
51                 showAlertDialog(getDialogMessage(false, -index));
52             } else {
53               mView.invalidate();
54             }
55         }
56 
sleep(long delayMillis)57         public void sleep(long delayMillis) {
58             this.removeMessages(0);
59             sendMessageDelayed(obtainMessage(0), delayMillis);
60         }
61     }
62 
63     @Override
onCreate(Bundle savedInstanceState)64     protected void onCreate(Bundle savedInstanceState) {
65         super.onCreate(savedInstanceState);
66         mView = new PurgeableBitmapView(this,  detectIfPurgeableRequest());
67         mRedrawHandler.sleep(0);
68         setContentView(mView);
69     }
70 
detectIfPurgeableRequest()71     private boolean detectIfPurgeableRequest() {
72         PackageManager pm = getPackageManager();
73         CharSequence labelSeq = null;
74         try {
75           ActivityInfo info = pm.getActivityInfo(this.getComponentName(),
76               PackageManager.GET_META_DATA);
77           labelSeq = info.loadLabel(pm);
78         } catch (NameNotFoundException e) {
79           e.printStackTrace();
80           return false;
81         }
82 
83         String[] components = labelSeq.toString().split("/");
84         if (components[components.length - 1].equals("Purgeable")) {
85             return true;
86         } else {
87             return false;
88         }
89     }
90 
getDialogMessage(boolean isOutOfMemory, int index)91     private String getDialogMessage(boolean isOutOfMemory, int index) {
92          StringBuilder sb = new StringBuilder();
93          if (isOutOfMemory) {
94              sb.append("Out of memery occurs when the ");
95              sb.append(index);
96              sb.append("th Bitmap is decoded.");
97          } else {
98              sb.append("Complete decoding ")
99                .append(index)
100                .append(" bitmaps without running out of memory.");
101          }
102          return sb.toString();
103     }
104 
showAlertDialog(String message)105     private void showAlertDialog(String message) {
106       AlertDialog.Builder builder = new AlertDialog.Builder(this);
107       builder.setMessage(message)
108              .setCancelable(false)
109              .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
110                  public void onClick(DialogInterface dialog, int id) {
111                                  }
112              });
113       AlertDialog alert = builder.create();
114       alert.show();
115     }
116 
117 
118 }
119