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android - BitmapFactory.decodeFile returns null even image exists

Saving the file:

FileOutputStream fo = null; 
try { 
        fo = this.openFileOutput("test.png", Context.MODE_WORLD_READABLE); 
} catch (FileNotFoundException e) { 
        e.printStackTrace(); 
} 
bitmap.compress(CompressFormat.PNG, 100, fo)

Loading the file:

String fname = this.getFilesDir().getAbsolutePath()+"/test.png"; 
Bitmap bMap = BitmapFactory.decodeFile(fname);
i.setImageBitmap(bMap);

The last line gives a null pointer exception, why is BitmapFactory.decodeFile returning null? I can verify that the file is getting saved correctly as I can pull it using adb and see the png displaying properly.

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1 Answer

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by (71.8m points)

If the NullPointerException is directly on this line:

i.setImageBitmap(bMap);

Then your problem is that i is null. Given that you're calling setImageBitmap(), I am guessing that i is an ImageView -- make sure your findViewById() call is working.

Also, you should use the following to get fname:

String fname=new File(getFilesDir(), "test.png").getAbsolutePath();


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