Passing android Bitmap Data within activity using Intent in Android

Question

I hava a Bitmap variable named bmp in Activity1 , and I want to send the bitmap to Activity2

Following is the code I use to pass it with the intent.

Intent in1 = new Intent(this, Activity2.class); in1.putExtra("image",bmp); startActivity(in1); 

And in Activity2 I try to access the bitmap using the following code

Bundle ex = getIntent().getExtras(); Bitmap bmp2 = ex.getParceable("image"); ImageView result = (ImageView)findViewById(R.Id.imageView1); result.setImageBitmap(bmp); 

The application runs without an exception but it does not give the expected result

Answer 1

Convert it to a Byte array before you add it to the intent, send it out, and decode.

//Convert to byte array ByteArrayOutputStream stream = new ByteArrayOutputStream(); bmp.compress(Bitmap.CompressFormat.PNG, 100, stream); byte[] byteArray = stream.toByteArray();  Intent in1 = new Intent(this, Activity2.class); in1.putExtra("image",byteArray); 

Then in Activity 2:

byte[] byteArray = getIntent().getByteArrayExtra("image"); Bitmap bmp = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length); 

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edit

Thought I should update this with best practice:

In your first activity, you should save the Bitmap to disk then load it up in the next activity. Make sure to recycle your bitmap in the first activity to prime it for garbage collection:

Activity 1:

try {     //Write file     String filename = "bitmap.png";     FileOutputStream stream = this.openFileOutput(filename, Context.MODE_PRIVATE);     bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);      //Cleanup     stream.close();     bmp.recycle();      //Pop intent     Intent in1 = new Intent(this, Activity2.class);     in1.putExtra("image", filename);     startActivity(in1); } catch (Exception e) {     e.printStackTrace(); } 

In Activity 2, load up the bitmap:

Bitmap bmp = null; String filename = getIntent().getStringExtra("image"); try {     FileInputStream is = this.openFileInput(filename);     bmp = BitmapFactory.decodeStream(is);     is.close(); } catch (Exception e) {     e.printStackTrace(); } 

Cheers!

Answer 2

Sometimes, the bitmap might be too large for encode&decode or pass as a byte array in the intent. This can cause either OOM or a bad UI experience.

I suggest to consider putting the bitmap into a static variable of the new activity (the one that uses it) which will carefully be null when you no longer need it (meaning in onDestroy but only if "isChangingConfigurations" returns false).