我爲我的問題準備了a simple test project at GitHub。DrawerLayout與ListView表示動作 - 如何在視圖上調用動作方法?
它是基於the well-known Navigation Drawer Example by Google - 通過在一個ListView音樂相關的操作右側抽屜擴展:
的動作是在RES /價值/ strings.xml中所有定義:
<string-array name="music_actions">
<item>Play</item>
<item>Pause</item>
<item>Stop</item>
<item>Shuffle</item>
</string-array>
<integer-array name="music_icons">
<item>@drawable/ic_play_arrow_black_24dp</item>
<item>@drawable/ic_pause_black_24dp</item>
<item>@drawable/ic_stop_black_24dp</item>
<item>@drawable/ic_shuffle_black_24dp</item>
</integer-array>
這裏是代碼讀取它們從資源(這非常適用):
public class MainActivity extends AppCompatActivity {
private String[] mActions;
private int[] mIcons;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mActions = getResources().getStringArray(R.array.music_actions);
TypedArray ta = getResources().obtainTypedArray(R.array.music_icons);
mIcons = new int[ta.length()];
for (int i = 0; i < mIcons.length; i++)
mIcons[i] = ta.getResourceId(i, R.drawable.ic_menu_black_24dp);
ta.recycle();
我的問題是:
從聽者的onItemClick
方法爲ListView - 如何調用片段中的相應的方法?
我只看到醜陋的方式與一個硬編碼switch
語句來完成它,就像這裏:
mRightDrawer.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, mActions) {
@Override
public View getView(int position, View convertView, ViewGroup parent) {
TextView view = (TextView) super.getView(position, convertView, parent);
view.setCompoundDrawablesWithIntrinsicBounds(mIcons[position], 0, 0, 0);
return view;
}
});
mRightDrawer.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if (mActiveFragment instanceof GameFragment) {
GameFragment fragment = (GameFragment) mActiveFragment;
switch (position) {
case 0:
fragment.playMusic(); // and then this calls myView.playMusic();
break;
case 1:
fragment.pauseMusic(); // calls myView.pauseMusic();
break;
}
}
mDrawerLayout.closeDrawer(mRightDrawer);
}
});
這是醜陋的,因爲我有跟蹤我的當前活動的片段,然後使用包裝方法最後調用方法在我的自定義視圖。
如何改善這種情況,我應該在我的自定義視圖中使用BroadcastReceiver?
我希望,我可以在我的資源中定義圖標+標題+動作,然後使用它們。
UPDATE:
現在我使用BroadcastReceiver
,但不知道它是一個apropriate溶液(或可能過重,重量是多少?)。
在我的片段我打電話:
@Override
public void onResume() {
super.onResume();
myView.register();
}
@Override
public void onPause() {
super.onPause();
myView.unregister();
}
而且在我的自定義視圖我有:
public class MyView extends View {
public final static String ACTION_PLAY = "de.afarber.myapp.play";
public final static String ACTION_PAUSE = "de.afarber.myapp.pause";
public final static String ACTION_STOP = "de.afarber.myapp.stop";
public final static String ACTION_SHUFFLE = "de.afarber.myapp.shuffle";
private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (ACTION_PLAY.equals(action))
playMusic();
else if (ACTION_PAUSE.equals(action))
pauseMusic();
else if (ACTION_STOP.equals(action))
stopMusic();
else if (ACTION_SHUFFLE.equals(action))
shuffleMusic();
}
};
public void register() {
IntentFilter filter = new IntentFilter();
filter.addAction(ACTION_PLAY);
filter.addAction(ACTION_PAUSE);
filter.addAction(ACTION_STOP);
filter.addAction(ACTION_SHUFFLE);
getContext().registerReceiver(mMessageReceiver, filter);
}
我寧願有某種「上下文菜單」的片段中 - 定義冠軍+圖標+動作 - 然後可以使用右側抽屜中的動作ListView ...
public void unregister() {
getContext().unregisterReceiver(mMessageReceiver);
}
如果你想使用的話,還有其他的三方圖書館很少。來自綠色機器人和rx android的EventBus。 – Raghunandan