Scale an image up to fill entire ImageView in Android

emmby picture emmby · Jul 12, 2011 · Viewed 76.7k times · Source

I'd like to scale an image up to take up the entire size of an ImageView. This is subtly different than using scaleType=fit_center because fit_center will leave bands around the image if the image aspect ratio does not exactly match the ImageView's aspect ratio. Instead, I would like the image to get centered and scaled up to completely fill the enclosing view, with any excess chopped off.

I'm able to accomplish this by computing my own custom image matrix during onCreate():

final Display display = getWindowManager().getDefaultDisplay();
final float screenWidth = display.getWidth();
final float screenHeight = display.getHeight();
final float imageWidth = splashView.getDrawable().getIntrinsicWidth();
final float imageHeight = splashView.getDrawable().getIntrinsicHeight();
final Matrix splashMatrix = new Matrix();
final float scale = Math.max(screenHeight/imageHeight,screenWidth/imageWidth);
splashMatrix.postScale( scale, scale );
splashView.setImageMatrix(splashMatrix);

This works fine, but it seems like there must be an easier away. Does anyone know of a way to scale up an image in an ImageView while both preserving the aspect ratio of the image and fully filling in the ImageView?

(Note: in my case my ImageView is taking up the full screen, so I use getWindowManager().getDisplay() to find the desired image size. You can't use splashView.getWidth()/getHeight() because the view hasn't been laid out yet and doesn't have a size)

Answer

roplacebo picture roplacebo · Jul 12, 2011

You can use android:scaleType="centerCrop". Keeps the aspect ratio and scales the image just like you want it.

For more information please go through the below link

http://developer.android.com/reference/android/widget/ImageView.html#attr_android:scaleType