在android中添加默認計時器

Question

我想在我的android應用程序中爲默認時間段創建一個計時器。 請幫我。我的應用程序正在計算一個班級的剩餘時間。如果課程在上午8:00開始，上午10:00結束，並且當前時間爲上午9:30時，計時器將顯示30分鐘。有誰能解決這個問題嗎？

Answer 1

您可以使用處理程序和joda時間來計算您的分鐘數。首先是活動中的靜態內部類。靜態類可防止內存泄漏。該處理程序將每分鐘運行一次。

編輯：在活動傳遞將允許您調用其他非靜態方法在activty

public static class TimeLeftHandler extends Handler { 
    private String startTime; 
    private String endTime; 
    private WeakReference<MyActivity> activity 

    public TimeLeftHandler(MyActivity activity, String startTime, String endTime) { 
     this.startTime = startTime; 
     this.endTime = endTime; 
     this.activity = new WeakReference<MyActivity>(activity); 
    } 

    @Override 
    public void handleMessage(Message msg) { 
     Log.d("Timeout", "Timeout thrown from SubjectSelection"); 
     DateTime now = new DateTime(); 
     DateTimeFormatter format = DateTimeFormat.forPattern("HH:mm"); 
     LocalTime classStartTime = format.parseLocalTime(startTime); 
     LocalTime classEndTime = format.parseLocalTime(endTime); 
     DateTime nowRoundFormat = new DateTime().dayOfMonth().roundFloorCopy(); 
     DateTime classStart = nowRoundFormat.plusHours(classStartTime.getHourOfDay()).plusMinutes(classStartTime.getMinuteOfHour()); 
     DateTime classEnd = nowRoundFormat.plusHours(classEndTime.getHourOfDay()).plusMinutes(classEndTime.getMinuteOfHour()); 

     if (now.isAfter(classStart) && now.isBefore(classEnd)) { 

      myMinutesTextView.setText("There are " + Minutes.minutesBetween(now, classEnd)); 
     } 

     //call non-static method. 
     activity.get().nonstaticMethod(); 

     sendEmptyMessageDelayed(0,60000); 


    } 

那麼活動：

public class MyActivity extends Activity { 
    private TextView myMinutesTextView; 
    private TimeLeftHandler timeLeftHandler; 


    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.mylayout); 

     myMinutesTextView = (TextView) findViewById(R.id.mytextview); 
     timeLeftHandler = new TimeLeftHandler("08:00", "10:00"); 
    } 

    @Override 
    protected void onStart() { 
     //start the handler 
     timeLeftHandler.sendEmptyMessage(0); 

    } 

    @Override 
    protected void onDestroy() { 
     //clean up. 
     timeLeftHandler.removeMessages(0); 



    } 

    private void nonstaticMethod() { 
     //Your code. 
    } 

    public static class TimeLeftHandler extends Handler { 
     ..... 
    } 


} 

對於Android Studio中的gradle這個構建你的build.gradle文件：

dependencies { 
    compile 'joda-time:joda-time:2.4' 
    compile 'joda-time:joda-time:2.4' 
    compile 'joda-time:joda-time:2.2' 
}