Question

我试图每2秒更新一次UI状态，UI包含文本视图和切换按钮，我的问题是文本视图正确更新但是切换按钮首先更新然后没有任何反应，这是使用的代码

@Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            tb = (ToggleButton) findViewById(R.id.tb);
            tv = (TextView) findViewById(R.id.tv);
            Timer myTimer = new Timer();
            myTimer.schedule(new TimerTask() {
                @Override
                public void run() {
                    UpdateGUI();

            }
        }, 0, 2000);
    }

    private void UpdateGUI() {
        i++;

        //tv.setText(String.valueOf(i));
        myHandler.post(myRunnable);
    }

    final Runnable myRunnable = new Runnable() {
        public void run() {

              runOnUiThread(new Runnable() {
                  @Override
                  public void run() {
                      tv.setText("Counter is "+i);
                      if ((i/2)==0){System.out.println("Condition true........"+i);tb.setChecked(true);}else{ System.out.println("Condition failed........"+i);tb.setChecked(false);}
                  }
              });
            }



    };
}

logcat中的输出是

System.out: Condition true........1
 I/System.out: Condition failed........2
01-07 11:04:49.304 17321-17321/com.example.vishal.updateui I/System.out: Condition failed........3
01-07 11:04:50.305 17321-17321/com.example.vishal.updateui I/System.out: Condition failed........4
01-07 11:04:51.304 17321-17321/com.example.vishal.updateui I/System.out: Condition failed........5
01-07 11:04:52.305 17321-17321/com.example.vishal.updateui I/System.out: Condition failed........6

Answer 1

您为切换错误的代码条件

您的代码：

if ((i / 2) == 0) {
        System.out.println("Condition true........" + i);
        tb.setChecked(true);
    } else {
        System.out.println("Condition failed........" + i);
        tb.setChecked(false);
    }

用这个更新：

if ((i % 2) == 0) {
            System.out.println("Condition true........" + i);
            tb.setChecked(true);
        } else {
            System.out.println("Condition failed........" + i);
            tb.setChecked(false);
        }

问题是“/”，因为如果i == 1那么值将是1/2 = 0但是在i / 2之后该值永远不会为0。

我希望在2秒延迟

1 个答案: