建议避免位内存错误内存、错误、建议

2023-09-12 04:07:27 作者:独活

我工作的Andr​​oid应用程序。该应用程序包含大量图像的观点。我有一个错误,我会尽量给尽可能多的信息可能希望有人可以给我一些建议。

I am working on an android application. The application has a view containing lots of image. I had an error, I will try to give as much information as possible hoping someone can give me some suggestions.

该应用程序是在所有的地方testings伟大的工作。不过,我收到了许多崩溃从用户: java.lang.OutOfMemoryError:位图大小超过VM预算

The application was working great on all the local testings. However, I received lots of crashes from users: java.lang.OutOfMemoryError: bitmap size exceeds VM budget

这是堆栈跟踪

0       java.lang.OutOfMemoryError: bitmap size exceeds VM budget
1   at  android.graphics.Bitmap.nativeCreate(Native Method)
2   at  android.graphics.Bitmap.createBitmap(Bitmap.java:507)
3   at  android.graphics.Bitmap.createBitmap(Bitmap.java:474)
4   at  android.graphics.Bitmap.createScaledBitmap(Bitmap.java:379)
5   at  android.graphics.BitmapFactory.finishDecode(BitmapFactory.java:498)
6   at  android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:473)
7   at  android.graphics.BitmapFactory.decodeResourceStream(BitmapFactory.java:336)
8   at  android.graphics.BitmapFactory.decodeResource(BitmapFactory.java:359)
9   at  android.graphics.BitmapFactory.decodeResource(BitmapFactory.java:385)

我最大的问题是,我没能即使在旧设备上进行本地重现该问题。

My biggest problem is that I was not able to reproduce the issue locally even on old devices.

我已经实现了很多事情,试图解决此问题:

I have implemented lots of things to try to resolve this:

没有内存泄漏:我确信没有内存泄漏的。我删除了意见时,我不需要他们。我还回收所有的位图并确保垃圾收集器,它应该工作。而且我实现了的onDestroy()方法,所有必要的步骤 图片大小缩放正确:之前获得的图像,我得到它的尺寸和计算 inSampleSize 堆大小:我也检测得到的图像前的最大堆大小,并确保有足够的空间。如果没有足够的予相应重新缩放图像。 No memory leaks: I made sure there is no memory leaks at all. I removed the views when I dont need them. I also recycled all the bitmaps and made sure the garbage collector is working as it should. And I implemented all the necessary steps in the onDestroy() method Image size scaled correctly: Before getting the image I get its dimension and calculate the inSampleSize. Heap size: I also detect the Max Heap size before getting the image and make sure there is enough space. If there is not enough I rescale the image accordingly.

code计算正确inSampleSize

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;
   }

code得到位图

    // decodes image and scales it to reduce memory consumption
   private static Bitmap decodeFile(File file, int newWidth, int newHeight)
   {// target size
      try
      {

         Bitmap bmp = MediaStore.Images.Media.getBitmap(getContext().getContentResolver(), Uri.fromFile(file));
         if(bmp == null)
         {
            // avoid concurrence
            // Decode image size
            BitmapFactory.Options option = new BitmapFactory.Options();

            // option = getBitmapOutput(file);

            option.inDensity = res.getDisplayMetrics().densityDpi < DisplayMetrics.DENSITY_HIGH ? 120 : 240;
            option.inTargetDensity = res.getDisplayMetrics().densityDpi;

            if(newHeight > 0 && newWidth > 0) 
                option.inSampleSize = calculateInSampleSize(option, newWidth, newWidth);

            option.inJustDecodeBounds = false;
            byte[] decodeBuffer = new byte[12 * 1024];
            option.inTempStorage = decodeBuffer;
            option.inPurgeable = true;
            option.inInputShareable = true;
            option.inScaled = true;

            bmp = BitmapFactory.decodeStream(new FileInputStream(file), null, option);
            if(bmp == null)
            {
               return null;
            }

         }
         else
         {
            int inDensity = res.getDisplayMetrics().densityDpi < DisplayMetrics.DENSITY_HIGH ? 120 : 240;
            int inTargetDensity = res.getDisplayMetrics().densityDpi;
            if(inDensity != inTargetDensity)
            {
               int newBmpWidth = (bmp.getWidth() * inTargetDensity) / inDensity;
               int newBmpHeight = (bmp.getHeight() * inTargetDensity) / inDensity;
               bmp = Bitmap.createScaledBitmap(bmp, newBmpWidth, newBmpHeight, true);
            }
         }

         return bmp;
      }
      catch(Exception e)
      {
         Log.e("Error calling Application.decodeFile Method params: " + Arrays.toString(new Object[]{file }), e);
      }
      return null;
   }

code来计算基于堆的大小为旧设备

private void calculateImagesSize()
   {
      // only for android older than HoneyComb that does not support large heap
      if(Build.VERSION.SDK_INT < Constants.HONEYCOMB)
      {
         long maxHeapSize = Runtime.getRuntime().maxMemory();
         long maxImageHeap = maxHeapSize - 10485760;
         if(Application.getResource().getDisplayMetrics().densityDpi >= DisplayMetrics.DENSITY_XHIGH)
         {
            maxImageHeap -= 12 * 1048576;
         }
         if(maxImageHeap < (30 * 1048576))
         {
            int screenHeight = Math.min(Application.getResource().getDisplayMetrics().heightPixels, Application.getResource()
               .getDisplayMetrics().widthPixels);
            long maxImageSize = maxImageHeap / 100;
            long maxPixels = maxImageSize / 4;
            long maxHeight = (long) Math.sqrt(maxPixels / 1.5);
            if(maxHeight < screenHeight)
            {
               drawableHeight = (int) maxHeight;
               drawableWidth = (int) (drawableHeight * 1.5);
            }
         }
      }
   }

我认为这个问题是与堆,也许有时操作系统不允许应用程序使用的maxheapsize。另外我最大的问题是,我无法重现的问题,因此当我尝试修复我必须等待一点点,看看如果用户仍然得到错误。

I think the problem is with the Heap, maybe sometimes the os doesn't allow the application to use the maxheapsize. Also my biggest problem is that I was not able to reproduce the issue, so when I try a fix I have to wait a little to see if users are still getting the error.

还有什么我可以尽量避免内存不足的问题?任何建议,将不胜AP preciated。非常感谢

What more could I try to avoid Out of memory issues? Any suggestions would be greatly appreciated. Thanks a lot

推荐答案

只需使用此功能去code ...这是你的error..because完美的解决方案我也得到同样的错误,我得到这个解决方案..

just use this function to decode...this is perfect solution for your error..because i also getting same error and i got this solution..

public static Bitmap decodeFile(File f,int WIDTH,int HIGHT){
     try {
         //Decode image size
         BitmapFactory.Options o = new BitmapFactory.Options();
         o.inJustDecodeBounds = true;
         BitmapFactory.decodeStream(new FileInputStream(f),null,o);

         //The new size we want to scale to
         final int REQUIRED_WIDTH=WIDTH;
         final int REQUIRED_HIGHT=HIGHT;
         //Find the correct scale value. It should be the power of 2.
         int scale=1;
         while(o.outWidth/scale/2>=REQUIRED_WIDTH && o.outHeight/scale/2>=REQUIRED_HIGHT)
             scale*=2;

         //Decode with inSampleSize
         BitmapFactory.Options o2 = new BitmapFactory.Options();
         o2.inSampleSize=scale;
         return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
     } catch (FileNotFoundException e) {}
     return null;
 }