Question

这是一个我希望每3秒后重复50次的代码。如果我用'for'循环或'while'循环调用此函数它不能正常工作请给我建议。

for (int i = 0; i < 50; i++) {
        Handler handler = new Handler();
        handler.postDelayed(new Runnable() {
            public void run() {
                Generate_Ballon();
            }
        }, delay);
    }

Answer 1

您可以使用CountDownTimer

参见示例，

new CountDownTimer(150000, 3000) 
{

     public void onTick(long millisUntilFinished) 
     {
         // You can do your for loop work here
     }

     public void onFinish() {
         mTextField.setText("done!");
     }
  }.start();

此处onTick()方法将每3秒执行一次。

Answer 2

为此，您应该使用Handler的postDelayed函数。它将在主UI线程上以指定的延迟运行您的代码，因此您将能够更新UI控件。

private int mInterval = 5000; // 5 seconds by default, can be changed later
  private Handler mHandler;

  @Override
  protected void onCreate(Bundle bundle) {
    ...
    mHandler = new Handler();
  }

  Runnable mStatusChecker = new Runnable() {
    @Override 
    public void run() {
      updateStatus(); //this function can change value of mInterval.
      mHandler.postDelayed(mStatusChecker, mInterval);
    }
  };

  void startRepeatingTask() {
    mStatusChecker.run(); 
  }

  void stopRepeatingTask() {
    mHandler.removeCallbacks(mStatusChecker);
  }

Answer 3

试试这个

   private static int i = 0; 

  void runHandler()
  {        
    Handler handler = new Handler();
    handler.postDelayed(new Runnable() {
        public void run() {
            i++;

            if(i<50)
                 runHandler();

            Generate_Ballon();
        }
    }, delay);
  }

Answer 4

private int count = 50;
private Handler handler = new Handler();
private Runnable r = new Runnable() {
    public void run() {
        Generate_Ballon();
        if (--count > 0) {
            handler.postDelayed(r, delay);
        }
    }
};

handler.postDelayed(r, delay);

在android中为特定时间重复一个方法

4 个答案: