android - 连续获取当前时间android

Question

我正在尝试为 android 制作一个闹钟应用程序，我应该做的第一件事就是不断获取系统的当前时间，所以我这样做了，但它只获取了当前的秒数，没有更多，有帮助吗？这是代码:

public class MainActivity extends Activity {
    public Button time;
    public TextView secondview;
    public static int hours, mins, secs;

    Handler main;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        time = (Button) findViewById(R.id.button1);
        secondview = (TextView) findViewById(R.id.textView2);

        new Thread(new Runnable() {

            @Override
            public void run() {
                secondview.setText(String.valueOf(secs));
                try {
                    Thread.sleep(1);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }).start();

        main = new Handler() {

            @Override
            public void handleMessage(Message msg) {
                super.handleMessage(msg);

                Calendar mycal = Calendar.getInstance();
                hours = mycal.get(Calendar.HOUR);
                mins = mycal.get(Calendar.MINUTE);
                secs = mycal.get(Calendar.SECOND);

                secondview.setText(String.valueOf(secs));
            }
        };
    }
}

Answer 1

Handler 和 Thread 是这类问题的糟糕选择。

要制作闹钟应用，请使用 AlarmManager .

您应该仔细选择要使用的计时器类型。 (ELAPSED_REALTIME，RTC，....)
对于闹钟应用，RTC_WAKEUP 是不错的选择。

和Android developer site has training如何使用 AlarmManager。

引用:

// Set the alarm to start at approximately 2:00 p.m.
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.set(Calendar.HOUR_OF_DAY, 14);

// With setInexactRepeating(), you have to use one of the AlarmManager interval
// constants--in this case, AlarmManager.INTERVAL_DAY.
alarmMgr.setInexactRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),
        AlarmManager.INTERVAL_DAY, alarmIntent);

还有一些用例的例子。