title: android keypad back button overriding password activity
body: <p>I have a problem regarding the back button on the android keypad.</p>
  
  <p>I have a main activity with a button, "Enter" that leads to another activity, Activity 2. Now I have password to protect Activity 2, so that when the button "Enter" is presseed a password prompt is shown to check input against stored password. Simple. </p>
  
  <p>Now if I were to leave Activity 2 and return to the main activity, and then i pressed the back button on the keypad, the password prompt does not show up and Activity 2 is accessed. Is there anyway to prevent this from happening?</p>
  
  <p>Please let me know if I was not clear, and I do not think the code need showing here.</p>