Full screen background image in an activity

There are several ways you can do it.

Option 1:

Create different perfect images for different dpi and place them in related drawable folder. Then set

android:background=”@drawable/your_image

Option 2:

Add a single large image. Use FrameLayout. As a first child add an ImageView. Set the following in your ImageView.

android:src="@drawable/your_image"
android:scaleType = "centerCrop"

References
https://stackoverflow.com/questions/16135984/full-screen-background-image-in-an-activity