[Android] Document the event callback system used in the Settings menu in large detail.

This commit is contained in:
Lioncash 2013-08-25 23:47:51 -04:00
parent 28008814a7
commit 786f09b1fa
1 changed files with 31 additions and 1 deletions

View File

@ -1,4 +1,4 @@
/** /**
* Copyright 2013 Dolphin Emulator Project * Copyright 2013 Dolphin Emulator Project
* Licensed under GPLv2 * Licensed under GPLv2
* Refer to the license.txt file included. * Refer to the license.txt file included.
@ -104,6 +104,36 @@ public final class PrefsActivity extends Activity implements ActionBar.TabListen
// Do nothing. // Do nothing.
} }
// How the event callback system works. The way dispatchGenericMotionEvent and dispatchKeyEvent
// work, is that they intercept ANY motion event or key event (respectively) and then follow the
// defined behavior in the overridden method.
//
// Now, to make this easier to understand, consider the following analogy:
//
// This class is a hydro-electric station that provides 'electricity' (key/motion events)
// to a series of 'houses' (in this case, fragments that implement the OnMotionConfigListener interface, or
// fragments that are housed within the ViewPager of this activity. So in a sense, the handline of
// key/motion events 'flows' from this class to the fragments housed in the ViewPager.
//
// While every single key/motion event is intercepted, every single intercepted event DOES NOT
// have to be handled by every fragment. Consider the fact that the only reason the InputConfigFragment
// requires the use of these, is so key binding events can be caught and handled. Other fragments
// have no need to use this.
//
// Consider the following representation of this activity as a ViewPager
//
// PrefsActivity
//
// Fragment Fragment Fragment
// 0 1 2
//
//
//
// Since fragments are NOT considered to be fully-fledged activities, but more of as a UI 'component'
// they do not have dispatch methods like Activities to override. So, in order to simulate this,
// simply implement the OnMotionConfigListener interface in the fragment, and then add the
// conditions of when it's acceptable to call those implemented methods in the fragment to
// the appropriate dispatch method.
// TODO: Eventually make correct implementations of these. // TODO: Eventually make correct implementations of these.
// Gets move(triggers, joystick) events // Gets move(triggers, joystick) events