Monodroid BitmapFactory.DecodeFileDescriptor Bitmap always null

Question

I use the following method to prevend a outofmemory exception, but the Bitmap ist always null. Has anybody an idea?

public Bitmap readBitmap(Android.Net.Uri selectedImage) {

        Bitmap bm = null;
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.InSampleSize = 9;
        AssetFileDescriptor fileDescriptor = null;
        try {
            fileDescriptor =  this.ContentResolver.OpenAssetFileDescriptor(selectedImage,"r");
        } catch (FileNotFoundException e) {
            Toast.MakeText(this, e.Message, ToastLength.Long);
        }
        finally{
            try {
                bm =  BitmapFactory.DecodeFileDescriptor(fileDescriptor.FileDescriptor, null, options);
                fileDescriptor.Close();
            } catch (IOException) {
            }
        }
        return bm;
}

score 1 · Answer 1 · answered Jan 13 '14 at 20:47

1

Yes. This is another bug of Google. Solution is to do this:

bm =  BitmapFactory.decodeStream(new FileInputStream(fileDescriptor));

Instead of

bm =  BitmapFactory.DecodeFileDescriptor(fileDescriptor.FileDescriptor, null, options);

answered Jan 13 '14 at 20:47

Uriel Frankel

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score 0 · Answer 2 · answered Jan 07 '13 at 10:01

0

BitmapFactory.DecodeFileDescriptor must be throwing an exception if bm is null.

answered Jan 07 '13 at 10:01

Ameen

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score 0 · Answer 3 · answered Jan 07 '13 at 10:06

0

On your catch, try modifying like this

} catch (IOException e) {
   Log.v ("Message", ""+e.message);
        }

So you could see whats the error that it returns to null

answered Jan 07 '13 at 10:06

Androyds

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android.resource://My.Paketname/drawable/tabbar is my uri My.Paketname is of course the correct name – anguish Jan 07 '13 at 10:20
then refer on my code here http://stackoverflow.com/questions/12559481/downloaded-image-can-not-be-displayed/12559586#12559586 – Androyds Jan 08 '13 at 03:31

score 0 · Answer 4 · answered Jan 07 '13 at 10:12

0

Perhaps the Uri is incorect and FileNotFoundException is thrown. But you can't see this because you are missing the show() method of the Toast in the catch clause.

Should be like this:

 Toast.MakeText(this, e.Message, ToastLength.Long).show();

answered Jan 07 '13 at 10:12

Andy Res

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hm okay, I don't know what could be wrong with my uri android.resource://My.Paketname/drawable/tabbar – anguish Jan 07 '13 at 10:29
Uri is correct, I checked this, I could set an imageview with this uri – anguish Jan 07 '13 at 11:01
Are you sure there insn't any exception thrown? Try to step through the program in debug mode and see the flow. – Andy Res Jan 07 '13 at 11:03
I tried to write the exception to the console, but there isn't one. Maybe the only hint is SkImageDecoder::Factory returned null in my Application Output – anguish Jan 07 '13 at 11:11
Could be. But I can't say that for sure. – Andy Res Jan 07 '13 at 11:12

Monodroid BitmapFactory.DecodeFileDescriptor Bitmap always null

4 Answers4