Android之Home鍵監聽封裝

眾所周知，我們監聽返回鍵事件，無法是下面兩個方法：

@Overridepublic void onBackPressed() {//do something//super.onBackPressed();}@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event) {if(keyCode == KeyEvent.KEYCODE_BACK){//do something}return super.onKeyDown(keyCode, event);}

於是乎，我們理所當然的想到，監聽Home鍵的方法是：if(keyCode == KeyEvent.KEYCODE_HOME)。但實際上，這樣是行不通的，因為此時home鍵的訊息在framework層就已經被攔截，所以，我們在應用中通過此方法是無法監聽到Home鍵的訊息的。那麼我們如何捕獲Home鍵事件，並作出相應處理呢？其實系統還是給我們發出廣播的，下面，就跟大家分享一下，封裝好了的監聽Home鍵的方法：

HomeWatcher類：

/** * Home鍵監聽封裝 *  * @author way *  */public class HomeWatcher {static final String TAG = "HomeWatcher";private Context mContext;private IntentFilter mFilter;private OnHomePressedListener mListener;private InnerRecevier mRecevier;// 回調介面public interface OnHomePressedListener {public void onHomePressed();public void onHomeLongPressed();}public HomeWatcher(Context context) {mContext = context;mFilter = new IntentFilter(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);}/** * 設定監聽 *  * @param listener */public void setOnHomePressedListener(OnHomePressedListener listener) {mListener = listener;mRecevier = new InnerRecevier();}/** * 開始監聽，註冊廣播 */public void startWatch() {if (mRecevier != null) {mContext.registerReceiver(mRecevier, mFilter);}}/** * 停止監聽，登出廣播 */public void stopWatch() {if (mRecevier != null) {mContext.unregisterReceiver(mRecevier);}}/** * 廣播接收者 */class InnerRecevier extends BroadcastReceiver {final String SYSTEM_DIALOG_REASON_KEY = "reason";final String SYSTEM_DIALOG_REASON_GLOBAL_ACTIONS = "globalactions";final String SYSTEM_DIALOG_REASON_RECENT_APPS = "recentapps";final String SYSTEM_DIALOG_REASON_HOME_KEY = "homekey";@Overridepublic void onReceive(Context context, Intent intent) {String action = intent.getAction();if (action.equals(Intent.ACTION_CLOSE_SYSTEM_DIALOGS)) {String reason = intent.getStringExtra(SYSTEM_DIALOG_REASON_KEY);if (reason != null) {Log.e(TAG, "action:" + action + ",reason:" + reason);if (mListener != null) {if (reason.equals(SYSTEM_DIALOG_REASON_HOME_KEY)) {// 短按home鍵mListener.onHomePressed();} else if (reason.equals(SYSTEM_DIALOG_REASON_RECENT_APPS)) {// 長按home鍵mListener.onHomeLongPressed();}}}}}}}

接下來，我們需要在應用中開啟監聽，下面是以在Activity中的應用為例：

/** * 應用HomeWatcher小例 *  * @author way *  */public class MainActivity extends Activity {private static final String TAG = "MainActivity";private HomeWatcher mHomeWatcher;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);mHomeWatcher = new HomeWatcher(this);mHomeWatcher.setOnHomePressedListener(new OnHomePressedListener() {@Overridepublic void onHomePressed() {Log.e(TAG, "onHomePressed");}@Overridepublic void onHomeLongPressed() {Log.e(TAG, "onHomeLongPressed");}});mHomeWatcher.startWatch();}@Overrideprotected void onPause() {super.onPause();mHomeWatcher.stopWatch();// 在onPause中停止監聽，不然會報錯的。}}