倒数计时器Textview

Question

我创建了这个应用，现在我想使用textview显示直到其他活动开始的秒数，但我不知道如何，我在countdowntimer内创建了一个txtview，但从未显示

Event=new String(Edt.getText().toString());
final int time = Integer.parseInt(sec.getText().toString());

Intent myInt = new Intent(MainActivity.this,Receiver.class);

myInt.putExtra("key",Event);
endingIntent pendingIntent = PendingIntent.getActivity(MainActivity.this,2,myInt,PendingIntent.FLAG_CANCEL_CURRENT);
AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);
am.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis()+(time*1000),pendingIntent);

new CountDownTimer(time*1000, 1000) {

    @Override
    public void onTick(long millisUntilFinished) {
    // TODO Auto-generated method stub
        txtV.setText("Activity starts"+millisUntilFinished/1000+"seconds"); // here is the txtV which isn't shown 
    }

    @Override
    public void onFinish() {
        // TODO Auto-generated method stub

    }
};

Answer 1

首先，您需要通过调用start方法来启动计数器

但是要小心，只能从创建视图的线程中更改视图。 一种方法是在视图上运行后 ：

    CountDownTimer timer = new CountDownTimer(time*1000, 1000) {

        @Override
        public void onTick(long millisUntilFinished) {
            txtV.post(new Runnable() {
                @Override
                public void run() {
                            txtV.setText("Activity starts"+millisUntilFinished/1000+"seconds"); // here is the txtV which isn't shown 
                }
            });
        }

        @Override
        public void onFinish() {
            // TODO Auto-generated method stub

        }
    };
    timer.start();