mHandler的handleMessage有時更新錯誤的TextView

Question

我有一個計劃的計時器 -

public void startTimer(long delay_minutes) { 
    final long delay = delay_minutes; 
    delay_countup = (double) delay; 

    //Start the scheduled time 
    departuretimer = new Timer(); 
    departuretimer.scheduleAtFixedRate(new TimerTask() { 
     public void run() { 
      countup = 0.0 + delay_countup; 
      Log.d("hi","Values 0" + delay_countup + countup); 
      mHandler.obtainMessage(1).sendToTarget(); 
      delay_countup = delay_countup + 0.5; 
      Log.d("hi","Values 1" + delay_countup); 
     } 
    }, 0, 30000); 
} 

public Handler mHandler = new Handler() { 
     public void handleMessage(Message msg) { 
      Log.d("hi","Values 3" + countup); 
      delay_time.setText(String.valueOf(countup) + "min"); 
      rootView.invalidate(); 
     } 
    }; 

日誌總是顯示正確的價值觀，但在UI中有時出現了問題。問題是，例如 -

delay_countup = 50.0 
countup = 50.0 
Textview updates as 50.0 //This is correct 

Now, 
delay_countup = 50.5 
countup = 50.5 
Textview updates as 0.5 //This is incorrect. I need 50.5 

有時會發生這種情況。爲什麼是這樣？

編輯：

在處理剛加入日誌太...

Values 0 = 34.5 34.5 
Values 3 = 0.5 

Answer 1

嘗試這種方式，改變你的mHandler等作爲，

public Handler mHandler = new Handler() { 
    public void handleMessage(Message msg) { 

    String result = (String)msg.obj; 

     delay_time.setText(result + "min"); 
     rootView.invalidate(); 
    } 
}; 

和

而不是mHandler.obtainMessage(1).sendToTarget();使用，

Message message = mHandler.obtainMessage(); 
message.obj = countup; 
mHandler.sendMessage(message); 

這可能會幫助你。