遊戲中常常需要監聽android HOME鍵，當HOME鍵下壓時，往往需要做一些狀態儲存，音效停止等操作，那麼如何做，才能監聽到HOME鍵呢？我們知道HOME是系統鍵，app中無法通過onKey這些函式來處理。要妥善的處理HOME鍵，首先需要看看HOME鍵下壓時，系統做了些什麼。

一、HOME鍵之來龍去脈

請見下圖：

二、app中對於HOME鍵廣播事件的接收

      首先，自定義一個BroadcastReceiver：

	class HomeKeyEventBroadCastReceiver extends BroadcastReceiver {

		static final String SYSTEM_REASON = "reason";
		static final String SYSTEM_HOME_KEY = "homekey";//home key
		static final String SYSTEM_RECENT_APPS = "recentapps";//long home key
		
		@Override
		public void onReceive(Context context, Intent intent) {
			String action = intent.getAction();
			if (action.equals(Intent.ACTION_CLOSE_SYSTEM_DIALOGS)) {
				String reason = intent.getStringExtra(SYSTEM_REASON);
				if (reason != null) {
					if (reason.equals(SYSTEM_HOME_KEY)) {
						// home key處理點
						
					} else if (reason.equals(SYSTEM_RECENT_APPS)) {
						// long home key處理點
					}
				}
			}
		}
	}
 

		receiver = new HomeKeyEventBroadCastReceiver();
		registerReceiver(receiver, new IntentFilter(Intent.ACTION_CLOSE_SYSTEM_DIALOGS));