Fragment Aktivität fangen onKeyDown und Verwendung in Fragmente

Question

Ich habe Fragment Aktivität mit Pager:

List<Fragment> fragments = new Vector<Fragment>(); 
    fragments.add(Fragment.instantiate(this, PastEventListFragment.class.getName(),bundle)); 
    fragments.add(Fragment.instantiate(this, EventListFragment.class.getName(),bundle)); 

    this.mPagerAdapter = new EventPagerAdapter(super.getSupportFragmentManager(), fragments); 
    // 
    ViewPager pager = (ViewPager)super.findViewById(R.id.viewpager1); 

    pager.setAdapter(this.mPagerAdapter); 
    pager.setCurrentItem(1); 

I onKeyDown Ereignis fangen:

@Override 
public boolean onKeyDown(int keyCode, KeyEvent event) { 
    if (keyCode == KeyEvent.KEYCODE_MENU) { 

    } 
    return super.onKeyDown(keyCode, event); 
} 

Die Frage ist: Wie Ereignis in allen Fragmenten verwenden i in dieser Aktivität instanziiert haben. Danke

Answer 1

Was Sie tun können, ist eine benutzerdefinierte Methode in Ihrer Fragmentklasse (n) zu definieren. Zum Beispiel:

public void myOnKeyDown(int key_code){ 
    //do whatever you want here 
} 

und diese Methode aufrufe, wenn ein Schlüssel-Down-Ereignis in Ihrer Aktivitätsklasse angehoben wird. Zum Beispiel:

@Override 
public boolean onKeyDown(int keyCode, KeyEvent event) { 
    if (keyCode == KeyEvent.KEYCODE_MENU) { 
     ((PastEventListFragment)fragments.get(0)).myOnKeyDown(keyCode); 
     ((EventListFragment)fragments.get(1)).myOnKeyDown(keyCode); 

     //and so on... 
    } 
    return super.onKeyDown(keyCode, event); 
} 

Answer 2

Wenn jemand interessed, wie es mit Boradcast zu tun:

In Ihrem Fragmente in onViewCreated

@Override 
public void onViewCreated(View view, Bundle savedInstanceState) { 
    super.onViewCreated(view, savedInstanceState); 


// Register to receive messages. 
// We are registering an observer (mMessageReceiver) to receive Intents 
// with actions named "custom-event-name". 
LocalBroadcastManager.getInstance(this).registerReceiver(mMessageReceiver, 
new IntentFilter("activity-says-hi")); 

...} 

// Our handler for received Intents. This will be called whenever an Intent 
// with an action named "custom-event-name" is broadcasted. 
private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() { 
@Override 
public void onReceive(Context context, Intent intent) { 
// Get extra data included in the Intent 

doSomethingCauseVolumeKeyPressed(); 

} 
}; 

Ihren KeyEvent - Code in Tätigkeit setzen

@Override 
public boolean dispatchKeyEvent(KeyEvent event) { 
    int action = event.getAction(); 
    int keyCode = event.getKeyCode(); 
    switch (keyCode) { 
     case KeyEvent.KEYCODE_VOLUME_UP: 
      if (action == KeyEvent.ACTION_DOWN) { 
       sendBroadcast(); 
      } 
      return true; 
     case KeyEvent.KEYCODE_VOLUME_DOWN: 
      if (action == KeyEvent.ACTION_DOWN) { 
       sendBroadcast(); 
      } 
      return true; 
     default: 
      return super.dispatchKeyEvent(event); 
    } 
} 

Ihr Sender Absender:

private void sendVolumeBroadcast(){ 
    Intent intent = new Intent("activity-says-hi"); 
    LocalBroadcastManager.getInstance(this).sendBroadcast(intent); 
} 

Answer 3

Ich habe Aktivitäts- und Fragmentklassen für die Ausführung von KeyEvents subclassiert. Für mich sieht es klarer aus als lokale Sendungen zu senden. Aber diese Lösung kann nicht so flexibel sein. Wählen Sie den bevorzugten Weg selbst aus. Hier

ist die Aktivität:

public abstract class KeyEventPassingActivity extends Activity { 

    public interface KeyEventListener extends View.OnKeyListener { 
     boolean isVisible(); 
     View getView(); 
    } 

    private final List<KeyEventListener> keyEventHandlerList = new ArrayList<>(); 

    @Override 
    public boolean dispatchKeyEvent(KeyEvent event) { 
     for (KeyEventListener handler : keyEventHandlerList) { 
      if (handleKeyEvent(handler, event)) { 
       return true; 
      } 
     } 
     return super.dispatchKeyEvent(event); 
    } 

    void addKeyEventHandler(@NonNull KeyEventListener handler) { 
     keyEventHandlerList.add(handler); 
    } 

    void removeKeyEventHandler(@NonNull KeyEventListener handler) { 
     keyEventHandlerList.remove(handler); 
    } 

    /** 
    * @return <tt>true</tt> if the event was handled, <tt>false</tt> otherwise 
    */ 
    private boolean handleKeyEvent(@Nullable KeyEventListener listener, KeyEvent event) { 
     return listener != null 
       && listener.isVisible() 
       && listener.onKey(listener.getView(), event.getKeyCode(), event); 
    } 
} 

Und das Fragment:

public abstract class KeyEventHandlingFragment extends Fragment 
     implements KeyEventPassingActivity.KeyEventListener { 

    @SuppressWarnings("deprecation") 
    @Override 
    public void onAttach(Activity activity) { 
     super.onAttach(activity); 
     if (activity instanceof KeyEventPassingActivity) { 
      ((KeyEventPassingActivity) activity).addKeyEventHandler(this); 
     } 
    } 

    @Override 
    public void onDetach() { 
     Activity activity = getActivity(); 
     if (activity instanceof KeyEventPassingActivity) { 
      ((KeyEventPassingActivity) activity).removeKeyEventHandler(this); 
     } 
     super.onDetach(); 
    } 
} 

Gist: https://gist.github.com/0neel/7d1ed5d26f2148b4168b6616337159ed