Develop Reference

How do I save the viewport bitmap of an imageview? - Android

I only want to save the bitmap of the image being displayed/cropped in the ImageView.
When I call this, it returns the entire bitmap:
Bitmap bitmap = ((BitmapDrawable) imageView.getDrawable()).getBitmap();

Use this to get the bitmap from ImageView
imageView.buildDrawingCache();
Bitmap bmap = imageView.getDrawingCache();

How to Get the BitMap from a NetworkImageView

I have a NetworkImageView where I download images from a server. However, the requirement is to have the ability to rotate the image after downloading the image. I have a rotate image function but I need to get the Bitmap associated to the NetworkImageView in order for me to rotate the bitmap. How can I access the BitMap from a NetworkImageView?

You can use below method to get bitmap of any view.
Bitmap bitmap = viewToBitmap(mImageView);
Bitmap bitmap = viewToBitmap(mLinearlayout);
Bitmap bitmap = viewToBitmap(mRelativelayout);
public Bitmap viewToBitmap(View view) {
Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
view.draw(canvas);
return bitmap;
}

Hope this helps
UPDATE
Create a volley image request.
After the image has been loaded and set inside the NetworkImageView this code will work. Else it will return a Null pointer since there is no view/image inside the NetworkImageView
mNetworkImageView = (NetworkImageView) view.findViewById(R.id.networkImage);
Bitmap bitmap = ((BitmapDrawable) mNetworkImageView.getDrawable()).getBitmap();
There is another way to use Volley and obtain the Bitmap.
Create an ImageRequest
inside the onResponse(), obtain the Bitmap and set it to your ImageView (Not NetworkImageView). I had mentioned this method in the comments above.

ActionBar logo scaled down behavior

I see that depending on how an image is set as the logo for ActionBar's home button, the image appears scaled down.
Image is scaled when using one of the following:
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.logo);
actionBar.setLogo(new BitmapDrawable(bmp));
Bitmap bmp = BitmapFactory.decodeFile(filePath);
actionBar.setLogo(new BitmapDrawable(bmp));
Image is NOT scaled, it looks OK when using one of the following:
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.logo);
actionBar.setLogo(getResources(), new BitmapDrawable(bmp));
Bitmap bmp = BitmapFactory.decodeFile(filePath);
actionBar.setLogo(getResources(), new BitmapDrawable(bmp));
actionBar.setLogo(R.drawable.logo)
For all cases, I call actionBar.setDisplayUseLogoEnabled(true).
Compared to 1 and 2, 3 and 4 respectively pass Resources parameter to setLogo.
I would like to understand why passing Resources influence the logo size.

How to get the whole bitmap attached to an ImageView?

I tried to get Bitmap attached to an ImageView, using ImageView.getDrawingCache(); But I found that the returned Bitmap was not the same as I'd like to get from the ImageView. It was always smaller than the real image.
I had known that, the method getDrawingCache() should not have the view if it is bigger than the screen as the visible portion of the view is only drawn and the cache holds only what is drawn.
Could I get the whole bitmap attached to a ImageView?

If you just want the Bitmap from a ImageView the following code may work for you:-
Bitmap bm=((BitmapDrawable)imageView.getDrawable()).getBitmap();
I think that's what you wanted.

If your drawble is not always an instanceof BitmapDrawable
Note: ImageView should be set before you do this.
Bitmap bitmap;
if (mImageView.getDrawable() instanceof BitmapDrawable) {
bitmap = ((BitmapDrawable) mImageView.getDrawable()).getBitmap();
} else {
Drawable d = mImageView.getDrawable();
bitmap = Bitmap.createBitmap(d.getIntrinsicWidth(), d.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
d.draw(canvas);
}
Your bitmap is stored in bitmap.
Voila!

Easiest way is to set tag in ImageView.
imageView.setImageBitmap(bitmap);
imageView.setTag(bitmap);
To get Tag from it
imageView.getTag();

Bizarre ImageView Bitmap Handling

I've encountered totally bizarre behavior in the way Android loads bitmaps into ImageView. For example, I have a 500x313 image file called urimg_01.jpg. With this code:
img.setImageResource(R.drawable.urimg_01);
Bitmap bitmap = ((BitmapDrawable) img.getDrawable()).getBitmap();
Log.v(TAG,"---------------------> bitmap width = "+bitmap.getWidth());
Log.v(TAG,"---------------------> bitmap height = "+bitmap.getHeight());
the ImageView bitmap is 750x470. (I have a Nexus S with 480x800 display.)
With this code, which reads a copy of the same file located in getFilesDir():
Log.v(TAG,"image file is "+filelist[0].getAbsolutePath());
FileInputStream fis = new FileInputStream(filelist[0]);
FileDescriptor fd = fis.getFD();
Bitmap bitmap = BitmapFactory.decodeFileDescriptor(fd);
if (bitmap != null) {
Log.v(TAG,"---------------------> bitmap width = "+bitmap.getWidth());
Log.v(TAG,"---------------------> bitmap height = "+bitmap.getHeight());
img.setImageBitmap(bitmap);
fis.close();
}
the ImageView bitmap is 500x313, as expected.
In the case of setImageResource(), where the devil is it getting 750x470 from?? And how do I get it to use the correct dimensions for resources in drawable?

Your resource is being scaled up because it's probably stored in a medium density folder and you're using a high density device. See Bitmap getWidth returns wrong value for details.

here you get your bitmap
Bitmap bitmap = BitmapFactory.decodeFileDescriptor(fd);
now scale it according to device height and width
Display display=this.getWindowManager().getDefaultDisplay();
int w=display.getWidth();
int h=display.getHeight();
Bitmap newBitmap=Bitmap.createScaledBitmap(oldBitmap, w, h, false);
//now setImage to background with new Bitmap
One important thing "this" should be activity context
:) cheers