Passing android Bitmap Data within activity using Intent in Android

Kotlin Code for send Bitmap to another activity by intent:

1- in First Activity :

          val i = Intent(this@Act1, Act2::class.java)
           var bStream  =  ByteArrayOutputStream()
            bitmap.compress(Bitmap.CompressFormat.PNG, 50, bStream)
            val byteArray = bStream.toByteArray()
            i.putExtra("image", byteArray )
            startActivity(i)

2- In Activity two (Read the bitmap image) :

 var bitmap : Bitmap? =null
    if (intent.hasExtra("image")){
      //convert to bitmap          
        val byteArray = intent.getByteArrayExtra("image")
        bitmap = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.size)
    }

3- if you need to set it as background for a view, like ConstraintLayout or... :

 if (bitmap != null) {
     //Convert bitmap to BitmapDrawable
     var bitmapDrawable = BitmapDrawable( resources , bitmap)
      root_constraintLayout.backgroundDrawable = bitmapDrawable
   }

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).

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);

---

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!

Simply we can pass only Uri of the Bitmap instead of passing Bitmap object. If Bitmap object is Big, that will cause memory issue.

FirstActivity.

intent.putExtra("uri", Uri);

From SecondActivity we get back bitmap.

Bitmap bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(),Uri.parse(uri));