显示照片的java内存不足
我在安卓项目中使用一个对话框来显示图像。第一个可以正常打开,但当我关闭它并再次执行该过程以显示另一个时,应用程序会出现内存错误(它运行在三星galaxy s3上,所以不应该成为问题)
错误:
10-24 11:25:45.575: E/dalvikvm-heap(29194): Out of memory on a 31961104-byte allocation.
10-24 11:25:45.580: E/AndroidRuntime(29194): FATAL EXCEPTION: main
10-24 11:25:45.580: E/AndroidRuntime(29194): java.lang.OutOfMemoryError
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.graphics.BitmapFactory.nativeDecodeStream(Native Method)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.graphics.BitmapFactory.decodeStream(BitmapFactory.java:587)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.graphics.BitmapFactory.decodeFile(BitmapFactory.java:389)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.graphics.BitmapFactory.decodeFile(BitmapFactory.java:418)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.graphics.drawable.Drawable.createFromPath(Drawable.java:882)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.widget.ImageView.resolveUri(ImageView.java:569)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.widget.ImageView.setImageURI(ImageView.java:340)
10-24 11:25:45.580: E/AndroidRuntime(29194): at com.directenquiries.assessment.tool.AddAsset.loadPhoto(AddAsset.java:771)
10-24 11:25:45.580: E/AndroidRuntime(29194): at com.directenquiries.assessment.tool.AddAsset$11.onClick(AddAsset.java:748)
10-24 11:25:45.580: E/AndroidRuntime(29194): at com.安卓.internal.app.AlertController$AlertParams$3.onItemClick(AlertController.java:936)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.widget.AdapterView.performItemClick(AdapterView.java:292)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.widget.AbsListView.performItemClick(AbsListView.java:1359)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.widget.AbsListView$PerformClick.run(AbsListView.java:2988)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.widget.AbsListView$1.run(AbsListView.java:3783)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.os.Handler.handleCallback(Handler.java:605)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.os.Handler.dispatchMessage(Handler.java:92)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.os.Looper.loop(Looper.java:137)
10-24 11:25:45.580: E/AndroidRuntime(29194): at 安卓.app.ActivityThread.main(ActivityThread.java:4517)
10-24 11:25:45.580: E/AndroidRuntime(29194): at java.lang.reflect.Method.invokeNative(Native Method)
10-24 11:25:45.580: E/AndroidRuntime(29194): at java.lang.reflect.Method.invoke(Method.java:511)
10-24 11:25:45.580: E/AndroidRuntime(29194): at com.安卓.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993)
10-24 11:25:45.580: E/AndroidRuntime(29194): at com.安卓.internal.os.ZygoteInit.main(ZygoteInit.java:760)
10-24 11:25:45.580: E/AndroidRuntime(29194): at dalvik.system.NativeStart.main(Native Method)
加载代码:
public void loadPhotoList(){
Cursor f = db.rawQuery("select * from stationphotos where StationObjectID = '"+ checkStationObjectID + "'", null);
final ArrayList<String> mHelperNames= new ArrayList<String>();
if(f.getCount() != 0) {
f.moveToFirst();
f.moveToFirst();
while(!f.isAfterLast()) {
mHelperNames.add(f.getString(f.getColumnIndex("FilePath")));
f.moveToNext();
}
}
f.close();
final String [] nameStrings = new String [mHelperNames.size()];
for(int i=0; i<mHelperNames.size(); i++)
nameStrings[i] = mHelperNames.get(i).toString();
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Select Picture");
builder.setItems(nameStrings, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int item) {
loadPhoto(mHelperNames.get(item).toString());
}
});
AlertDialog alert = builder.create();
alert.show();
}
public void loadPhoto(String imagepath){
Dialog dialog = new Dialog(this);
dialog.setContentView(R.layout.activity_show_image);
dialog.setTitle("Image");
dialog.setCancelable(true);
ImageView img = (ImageView) dialog.findViewById(R.id.imageView1);
img.setImageResource(R.drawable.ico_partial);
Uri imgUri = Uri.parse(imagepath);
img.setImageURI(imgUri);
dialog.show();
}
编辑:我现在使用什么使它工作:
public static Bitmap decodeSampledBitmapFromFile(String imagePath, int reqWidth, int reqHeight) {
// 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 = calculateInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeFile(imagePath, options);
}
public static int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
if (width > height) {
inSampleSize = Math.round((float)height / (float)reqHeight);
} else {
inSampleSize = Math.round((float)width / (float)reqWidth);
}
}
return inSampleSize;
}
img.setImageBitmap(decodeSampledBitmapFromFile(imagepath, 500, 500));
# 1 楼答案
我经历过这种情况,我不知道我的答案是否是最佳实践,但是
这可能是您的问题:
如果你加载了一个大的图像,那么你可能会耗尽内存。此外,如果在加载一系列图像时未能使用适当的内存管理,您将耗尽内存
我使用BitmapFactory对文件进行解码,并使用BitmapFactory.Options创建一个新的sclaed位图,然后显示在屏幕上
这个想法是BitmapFactory。选项使您能够更好地控制图像可能使用的潜在内存。例如,不需要在甚至不支持这些分辨率的屏幕上以全尺寸显示1920x1080图像
有一些相关的stackoverflow问题可能会对您有所帮助,特别是:Handling large Bitmaps,它主要关注BitmapFactory。选项
inJustDecodeBounds
最后,我找到了这个名为Aquery的伟大的轻量级库。它有一整套处理大型文件的方法,到目前为止,它做得很好。很值得一看。在web开发方面,它使用了与Jquery类似的范例(因此得名),并引入了一种用于操作视图的较短语法。他们文档的以下部分涉及本地和远程源的图像加载,包括回退图像:
http://code.google.com/p/android-query/wiki/ImageLoading