Question

在我的Android应用程序中我正在使用Timer schedule.but得到Timer-0致命异常如下所示。我可以删除它。我也提到了下面的代码 -

01-28 13:44:41.142: E/AndroidRuntime(1307): FATAL EXCEPTION: Timer-0
01-28 13:44:41.142: E/AndroidRuntime(1307):android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
01-28 13:44:41.142: E/AndroidRuntime(1307):     at android.view.ViewRoot.checkThread(ViewRoot.java:2932)
01-28 13:44:41.142: E/AndroidRuntime(1307):     at android.view.ViewRoot.invalidateChild(ViewRoot.java:642)
01-28 13:44:41.142: E/AndroidRuntime(1307):     at android.view.ViewRoot.invalidateChildInParent(ViewRoot.java:668)
01-28 13:44:41.142: E/AndroidRuntime(1307):     at android.view.ViewGroup.invalidateChild(ViewGroup.java:2511)
01-28 13:44:41.142: E/AndroidRuntime(1307):     at android.view.View.invalidate(View.java:5279)
01-28 13:44:41.142: E/AndroidRuntime(1307):     at android.view.View.setBackgroundDrawable(View.java:7626)
01-28 13:44:41.142: E/AndroidRuntime(1307):     at android.view.View.setBackgroundResource(View.java:7535)
01-28 13:44:41.142: E/AndroidRuntime(1307):     at com.example.iqtest.PlayGame$1.run(PlayGame.java:61)
01-28 13:44:41.142: E/AndroidRuntime(1307):     at java.util.Timer$TimerImpl.run(Timer.java:284)

和代码是 -

protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.next);
    but1=(Button) findViewById(R.id.b1);
    but2=(Button) findViewById(R.id.b2);
    but3=(Button) findViewById(R.id.b3);

    myTimer = new Timer();

    myTimer.schedule(new TimerTask() {      

        @Override
        public void run() {
            Random rand=new Random();
            int num=rand.nextInt(9)+1;

            num = rand.nextInt(buttonIds.length);
            int buttonId = buttonIds[num];
            Button bb=(Button) findViewById(buttonId);

            Drawable a=bb.getBackground();
            if(getResources().getDrawable(R.drawable.happy).equals(a))
             bb.setBackgroundResource(R.drawable.happy);
            else
                bb.setBackgroundResource(R.drawable.whoa);
        }
    },0, 1000);
}

Answer 1

使用runOnUiThread更新来自Timertask run Method的UI元素：

 myTimer.schedule(new TimerTask() {      

 @Override
 public void run() {
  Current_Activity.this.runOnUiThread(new Runnable() {
    public void run() {
        // update UI here
    }
 });
 }
},0, 1000);

Answer 2

您可以使用CountDownTimer代替Timer：

Timer timer = new CountDownTimer(Long.MAX_VALUE, 1000) {
    public void onTick(long millisUntilFinished) {
        // the code in the method run
    }

    public void onFinish() {

    }
};

将在UI线程中调用方法onTick和onFinish。

要使计时器开始执行其操作，请运行：timer.start()

Answer 3

这很简单，你正在安排定时器，但从不取消它。因此，预定的任务将在队列中并等待轮到它。到那时它应该被执行你的Activity可能不在前台而且它无法找到视图。所以它抛出了致命的例外。为了解决上述问题，您需要通过调用myTimer.cancel()来取消任务，无论何时您从该特定活动开始。

否则

使用Handler类。

Answer 4

runOnUiThread(new Runnable() {
     public void run() {

       //stuff that updates ui

    }
});

试试这个

也看看

Android "Only the original thread that created a view hierarchy can touch its views."

CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch views

Only the original thread that created a view hierarchy can touch its views

android Timer中的致命异常

4 个答案: