0

我正在尝试更改相对布局背景颜色，例如闪烁首先设置为绿色，然后在相对布局中设置白色背景颜色。但是，我的问题线程执行第二次强制关闭错误并尝试修复很多方法但不起作用。这是我的代码：

       isThreadRunning = true;
       relative=(RelativeLayout) findViewById(R.id.layout);
       Runnable runnable = new Runnable() {
                 public void run() {
                   int i=0;
                   while(isThreadRunning) {
                       if(i==0)
                       {
                       relative.setBackgroundColor(Color.GREEN);
                       i=1;
                       }
                       else
                       {
                         relative.setBackgroundColor(Color.BLACK);
                         i=0;
                       }
                       try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } 

                   }
               }
               };
               new Thread(runnable).start();

我在 logcat 中遇到错误，如下所示：

07-10 17:48:42.752: W/dalvikvm(2060): threadid=9: thread exiting with uncaught exception (group=0x40015560)
07-10 17:48:42.756: E/AndroidRuntime(2060): FATAL EXCEPTION: Thread-10
07-10 17:48:42.756: E/AndroidRuntime(2060): android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
07-10 17:48:42.756: E/AndroidRuntime(2060):     at android.view.ViewRoot.checkThread(ViewRoot.java:2932)
07-10 17:48:42.756: E/AndroidRuntime(2060):     at android.view.ViewRoot.invalidateChild(ViewRoot.java:642)
07-10 17:48:42.756: E/AndroidRuntime(2060):     at android.view.ViewRoot.invalidateChildInParent(ViewRoot.java:668)
07-10 17:48:42.756: E/AndroidRuntime(2060):     at android.view.ViewGroup.invalidateChild(ViewGroup.java:2511)
07-10 17:48:42.756: E/AndroidRuntime(2060):     at android.view.View.invalidate(View.java:5279)
07-10 17:48:42.756: E/AndroidRuntime(2060):     at android.view.View.setBackgroundDrawable(View.java:7626)
07-10 17:48:42.756: E/AndroidRuntime(2060):     at android.view.View.setBackgroundColor(View.java:7516)
07-10 17:48:42.756: E/AndroidRuntime(2060):     at com.example.screen_blinker.Home_activity$1.run(Home_activity.java:44)
07-10 17:48:42.756: E/AndroidRuntime(2060):     at java.lang.Thread.run(Thread.java:1019)

我的代码有什么问题以及如何解决这个问题？

提前致谢！

4

3 回答 3

0

您只能在主线程中更改视图元素。如果您在另一个线程中，请使用以下命令：

    Current_Activity.this.runOnUiThread(new Runnable() {

                @Override
                public void run() {
                    // TODO Auto-generated method stub

                }
            });
于 2012-07-10T12:33:26.130 回答
0

您需要在 GUI 线程上执行与 GUI 相关的任务。

relative.setBackgroundColor(Color.GREEN);像这样包裹你runOnUiThread：

Current_Activity.this.runOnUiThread(new Runnable() {
        @Override
        public void run() {
            relative.setBackgroundColor(Color.GREEN);               
        }
于 2012-07-10T12:33:40.030 回答
0

将代码更改为使用runOnUiThread从非 UI 线程更新 UI 元素：

public void myThread(){
    Thread th=new Thread(){

     @Override
     public void run(){
      try
      {
       while(isThreadRunning)
       {
       Thread.sleep(1000);
       Current_Activity.this.runOnUiThread(new Runnable() {

        @Override
        public void run() {
         // TODO Auto-generated method stub
             if(i==0)
            {
               relative.setBackgroundColor(Color.GREEN);
               i=1;
            }
            else
              {
               relative.setBackgroundColor(Color.BLACK);
               i=0;
              }

           }
       });
       }
      }catch (InterruptedException e) {
    // TODO: handle exception
   }
}
    };
    th.start();
   }
于 2012-07-10T12:34:26.833 回答