我开发了一个用于书籍阅读的Android应用程序。 Book页面和音频从Amazon Bucket下载。下载后，它存储在SD卡上。
我为下一页和上一页放置了两个按钮。当我显示页面它给了我内存异常。
11-03 10:59:39.199: E/AndroidRuntime(13566): FATAL EXCEPTION: main
11-03 10:59:39.199: E/AndroidRuntime(13566): java.lang.OutOfMemoryError
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:493)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.graphics.BitmapFactory.decodeFile(BitmapFactory.java:299)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.graphics.BitmapFactory.decodeFile(BitmapFactory.java:324)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.graphics.drawable.Drawable.createFromPath(Drawable.java:880)
11-03 10:59:39.199: E/AndroidRuntime(13566): at org.Infoware.childrenbible.GeneralHelper.setImgfromSDCard(GeneralHelper.java:608)
11-03 10:59:39.199: E/AndroidRuntime(13566): at org.Infoware.childrenbible.CoverPageActivity.onCreate(CoverPageActivity.java:205)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.app.Activity.performCreate(Activity.java:4465)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.app.ActivityThread.access$600(ActivityThread.java:123)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.os.Handler.dispatchMessage(Handler.java:99)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.os.Looper.loop(Looper.java:137)
11-03 10:59:39.199: E/AndroidRuntime(13566): at android.app.ActivityThread.main(ActivityThread.java:4424)
11-03 10:59:39.199: E/AndroidRuntime(13566): at java.lang.reflect.Method.invokeNative(Native Method)
11-03 10:59:39.199: E/AndroidRuntime(13566): at java.lang.reflect.Method.invoke(Method.java:511)
11-03 10:59:39.199: E/AndroidRuntime(13566): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
11-03 10:59:39.199: E/AndroidRuntime(13566): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
11-03 10:59:39.199: E/AndroidRuntime(13566): at dalvik.system.NativeStart.main(Native Method)
这是我的Java代码：
public class PageReadActivity extends Activity
{
Bitmap bitmap;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
try
{
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.pageread_layout);
}
catch (Exception ex)
{
ex.printStackTrace();
Log.d(TAG, "Error in onCreate");
}
}
@Override
protected void onStart() {
// TODO Auto-generated method stub
super.onStart();
displayPage(product_code, page_Index);
btnNext.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
page_Index = page_Index + 1;
displayPage(product_code, page_Index);
}
});
btnPrevious.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
page_Index = page_Index - 1;
displayPage(product_code, page_Index);
}
});
}
private void displayPage(String product_code, int ind)
{
try
{
String imageName = product_code + ind + ".jpg";
String imgFilePath = objHelper.getFullFilePath(imageName);
File imageFile = new File(imgFilePath);
imgViewPage = new ImageView(myContext);
if(imageFile.exists())
{
bitmap = objHelper.decodeSampledBitmapFromResource(imageName,objHelper.screenWidth,objHelper.screenHeight);
imgViewPage.setImageBitmap(bitmap);
bitmap = null;
String audioName = product_code+"_audio" + ind + ".mp3";
String audioFilePath = objHelper.getFullFilePath(audioName);
File audioFile = new File(audioFilePath);
if(audioFile.exists())
{
progressBarWaiting.setVisibility(View.INVISIBLE);
stopAudio();
playAudio(ind);
}
}
else
{
System.out.println("Image not exists.....");
}
}
catch (Exception ex)
{
ex.printStackTrace();
Log.e(TAG, "ERROR in displayPage");
}
}
@Override
protected void onDestroy()
{
super.onDestroy();
objHelper.unbindDrawables(findViewById(R.id.pageReadLayout));
System.gc();
}
public void unbindDrawables(View view)
{
if(view.getBackground() != null)
{
view.getBackground().setCallback(null);
}
if(view instanceof ViewGroup && !(view instanceof AdapterView))
{
for (int i = 0; i < ((ViewGroup) view).getChildCount(); i++)
{
unbindDrawables(((ViewGroup) view).getChildAt(i));
}
((ViewGroup) view).removeAllViews();
}
}
public Bitmap decodeSampledBitmapFromResource(String fileName,int reqWidth, int reqHeight)
{
String imagePath = getFullFilePath(fileName);
@SuppressWarnings("unused")
File imgFile = new File(imagePath);
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(imagePath,options);
// Calculate inSampleSize
options.inSampleSize = 1;
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeFile(imagePath,options);
}
}
答案 0 :(得分：8)
位图转换图像的原始大小x 4.因此它占用了更多的堆，这是由android为您的应用指定的。
不再需要位图时使用此功能
bitmap.recycle();
bitmap = null;
答案 1 :(得分：2)
我的猜测是Bitmaps处理不当而且正在创建一个OutofMemoryException。位图应在不使用时回收。拿一个look here.。另外have a look at how to find memory leaks here使用MAT Analyzer。
答案 2 :(得分：0)
只需更改inSampleSize = 4，如果不能正常工作，请将其增加2秒