My application has a question and a radiogroup with four radio buttons and a next button in each screen. I need to write the code to, when ii press the down arrow in the android key pad it needs check the first radio button, and again if i pressed the down arrow it needs to go to the next radio button, and when i press the enter (the middle button) it needs to press the finish button. how to write the code to navigate among the all radio button elements in the interface with the keypad arrow keys.