Create Drawable with specific height

I want to create a drawable object with a width equal to the screen's width and display 3 images inside the drawable. I know the last part can be done using a LayerDrawable object, but I don't know how to set the drawable sizes. What would be the best way to do this?

开发者_开发百科

Thank you and best regards

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http://www.anddev.org/resize_and_rotate_image_-_example-t621.html
i hope this help..