android notification 總結

今天使用Notification 遇到了 些詭異的問題，記錄下來，以備後用。

1. 需求：定時獲取消息，並在通知欄顯示；點擊通知欄彈出消息框
2. 實現：

   AlarmManager + BroadcastReceiver + NotificationManager

   部分代碼如下：

   public static void setupGetMessageAlarm(Context context) {
           Log.d("msg", "setupGetMessageAlarm");
           AlarmManager am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
           Intent intent = new Intent(context, MsgAlarmReceiver.class);
           intent.setAction(INTENT_GET_MESSAGE_ALARM);
           PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);
   
           Calendar calendar1 = Calendar.getInstance();
           calendar1.set(Calendar.HOUR_OF_DAY, 12);
           calendar1.set(Calendar.MINUTE, 30);
           Calendar calendar2 = Calendar.getInstance();
           calendar2.set(Calendar.HOUR_OF_DAY, 18);
           calendar2.set(Calendar.MINUTE, 30);
           am.setRepeating(AlarmManager.RTC_WAKEUP, calendar1.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pi);
           am.setRepeating(AlarmManager.RTC_WAKEUP, calendar2.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pi);
       }
   

   
   

   public class MsgAlarmReceiver extends BroadcastReceiver {
       private Context mContext;
       private MsgInfo mMsgInfo;
       private NotificationManager mNM;
       private static final int NOTIFICATION_ID = R.layout.activity_message;
   
       @Override
       public void onReceive(final Context context, Intent intent) {
           mContext = context;
           mNM = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
                           Intent intent = new Intent(mContext, MessageActivity.class);
                           Bundle bundle = new Bundle();
                           bundle.putParcelable(MsgInfo.class.getName(), mMsgInfo);
                           intent.putExtras(bundle);
                           PendingIntent pendingIntent = PendingIntent.getActivity(mContext, 0, intent,
                                   PendingIntent.FLAG_UPDATE_CURRENT);
   
                           Notification notification = new Notification();
                           notification.icon = R.drawable.ic_app;
                           notification.tickerText = mContext.getString(R.string.notification_ticker_message);
                           notification.setLatestEventInfo(mContext, mMsgInfo.getTitle(), noticeMessage, pendingIntent);
                           notification.flags = Notification.FLAG_AUTO_CANCEL;
                           mNM.notify(NOTIFICATION_ID, notification);
       }
   }

3. 出現問題：

• 點擊通知，不彈出MessageActivity

解決方法：重啓手機；原因未知

• 傳遞給activity的bundle爲null

 解決方法：將PendingIntent的flag設爲 PendingIntent.FLAG_UPDATE_CURRENT；

原因見 點擊打開鏈接   待研究

• 通知欄消息點擊後不消失

      解決方法：notification添加flag​

                        notification.flags = Notification.FLAG_AUTO_CANCEL;

• 運行程序立即彈出notification

原因：設置的時鐘已過時

解決方法：設置時鐘時增加判斷，已過時則設置爲第二天執行，

        Calendar calendar1 = Calendar.getInstance();
        calendar1.set(Calendar.HOUR_OF_DAY, 12);
        calendar1.set(Calendar.MINUTE, 30);
        Calendar calendar2 = Calendar.getInstance();
        calendar2.set(Calendar.HOUR_OF_DAY, 18);
        calendar2.set(Calendar.MINUTE, 30);
        // 若時間已過，設置下一天執行。
        long alertTime1 = calendar1.getTimeInMillis(),
                alertTime2 = calendar2.getTimeInMillis();
        if(System.currentTimeMillis() > alertTime1){
            alertTime1 += AlarmManager.INTERVAL_DAY;
        }
        if(System.currentTimeMillis() > alertTime2){
            alertTime2 += AlarmManager.INTERVAL_DAY;
        }
        am.setRepeating(AlarmManager.RTC_WAKEUP, alertTime1, AlarmManager.INTERVAL_DAY, pi);
        am.setRepeating(AlarmManager.RTC_WAKEUP, alertTime2, AlarmManager.INTERVAL_DAY, pi);

• 設置的第一個定時器不生效

原因：setRepeating的解釋如下，

    /**
     * Schedule a repeating alarm.  <b>Note: for timing operations (ticks,
     * timeouts, etc) it is easier and much more efficient to use
     * {@link android.os.Handler}.</b>  If there is already an alarm scheduled
     * for the same IntentSender, it will first be canceled.......

看來要想設置兩個Intent相同，僅僅是時間不同的鬧鈴是不能簡單的採用設置兩次的方法了。

從網上搜索到一種實現方式，每次找下一個時間點設置鬧鈴，鬧鈴執行時再設置下一個鬧鈴。代碼如下：

    public static void setupNextGetMessageAlarm(Context context) {
        AlarmManager am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
        Intent intent = new Intent(context, MsgAlarmReceiver.class);
        intent.setAction(INTENT_GET_MESSAGE_ALARM);
        PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);

        Calendar cal = Calendar.getInstance();
        cal.setTimeInMillis(System.currentTimeMillis());
        // 鬧鈴時間
        final int HOUR_1 = 12, MINITE_1 = 30, HOUR_2 = 18, MINITE_2 = 30;

        if(cal.get(Calendar.HOUR_OF_DAY) <= HOUR_1 && cal.get(Calendar.MINUTE) < MINITE_1){
            cal.set(Calendar.HOUR_OF_DAY, HOUR_1);
            cal.set(Calendar.MINUTE, MINITE_1);
        }else if(cal.get(Calendar.HOUR_OF_DAY) <= HOUR_2 && cal.get(Calendar.MINUTE) < MINITE_2){
            cal.set(Calendar.HOUR_OF_DAY, HOUR_2);
            cal.set(Calendar.MINUTE, MINITE_2);
        }else{
            cal.set(Calendar.HOUR_OF_DAY, HOUR_1);
            cal.set(Calendar.MINUTE, MINITE_1);
        }
        cal.set(Calendar.SECOND, 0);
        cal.set(Calendar.MILLISECOND, 0);
        // 若時間已過，設置下一天執行。
        long alertTime1 = cal.getTimeInMillis();
        if(System.currentTimeMillis() > alertTime1){
            alertTime1 += AlarmManager.INTERVAL_DAY;
        }
        am.setRepeating(AlarmManager.RTC_WAKEUP, alertTime1, AlarmManager.INTERVAL_DAY, pi);
    }

    @Override
    public void onReceive(final Context context, Intent intent) {
        LogUtil.d(TAG, "MsgAlarmReceiver");
        mContext = context;
        // 設置下一個鬧鈴
        MsgUtils.setupNextGetMessageAlarm(context);
    ......