Android Change Shape of Button

I'm trying to design a button for an android application like this:

The length of 开发者_StackOverflow社区the button will be determined based on the size of the text. The text will change during runtime depending on the page the button is displayed on. Does anyone have an idea on how I can achieve this?

Just use a regular button with 9-patch png image as a background. More about 9-patch can be read here: Draw 9-patch.