定时器 timer

    private Timer mTimer;
    private TimerTask mTimerTask;

    mTimer = new Timer();

    mTimerTask = new TimerTask() {
            
            @Override
            public void run() {
                // TODO Auto-generated method stub
                Log.d("11", "timer + ----" + i);
                i++;
            }
        };

        mTimer.schedule(mTimerTask, 500, 500);

定时器和定时器任务都可以cancel

cancel后再schedule  会报空指针

倒计时定时器：

public class CountTimer extends CountDownTimer {

   private final String tag = "CountDownUtils";
   private Button tv_display;

   public CountTimer(Button textView, long millisInFuture, long countDownInterval) {
      super(millisInFuture, countDownInterval);
      // TODO Auto-generated constructor stub   tv_display = textView;
   }

   @Override
   public void onFinish() {
      // TODO Auto-generated method stub  timerButton.setFocusable(true);
      tv_display.setTextColor(Color.WHITE);
      tv_display.setText("重新发送");
   }

   @Override
   public void onTick(long millisUntilFinished) {
      // TODO Auto-generated method stub  tv_display.setTextColor(getResources().getColor(R.color.titletext_unsel_color));
      tv_display.setText("重新发送\n" + "(" + (millisUntilFinished / 1000 - 1) + " s)");

   }

}

private void startCountTimer() {
   if (countTimer != null) {
      countTimer.cancel();
      countTimer = null;
   }
   countTimer = new CountTimer(timerButton, 60 * 1000, 1000);
   countTimer.start();
   timerButton.setFocusable(false);
}

private void endCountTimer() {
   if (countTimer != null) {
      countTimer.cancel();
      countTimer = null;
   }
}

用闹钟定时：

public static void startPollingService(Context context, int seconds,
      Class<?> cls, String action) {

   AlarmManager manager = (AlarmManager) context
         .getSystemService(Context.ALARM_SERVICE);

   Intent intent = new Intent(context, cls);
   intent.setAction(action);
   PendingIntent pendingIntent = PendingIntent.getService(context, 0,
         intent, PendingIntent.FLAG_UPDATE_CURRENT);

   long triggerAtTime = SystemClock.elapsedRealtime();

   manager.setRepeating(AlarmManager.ELAPSED_REALTIME, triggerAtTime,
         seconds * 1000, pendingIntent);
}