AsyncTask OnPostExecute 不更新 TextView [英] AsyncTask OnPostExecute not updating TextView

问题描述

我有一个 AsyncTask 正在运行.我有一个 TextView，我模仿了 Toast 最初产生的消息.我想在 OnPostExecute 成功后清除 TextView 但它没有这样做.任务完成 Toast 工作正常.如何将 OnPostExecute 中的 TextView 设置为空白?用户仍然在 TextView 所在的显示屏幕上.

I have an AsyncTask running. I have a TextView that I mimic the message a Toast initially produces. I want to clear the TextView upon success in OnPostExecute but it not doing so. The task complete Toast works fine. How do I set the TextView in the OnPostExecute to blank? The user is still on the display screen where the TextView is.

出现错误情况的代码如下:

Code is as follows for an error condition:

@Override
protected void onPostExecute(Void result) 
 { FetchingImage=0;
  if(webLoadError>0)
   {
    TextView text = (TextView) findViewById(R.id.textView2);
    String temp=" ";
    text.setText(temp);
    Toast.makeText(getApplicationContext(), "Image not available from the internet.
Default or last image loaded.
Try again later.",Toast.LENGTH_LONG).show();
    }  
  }

推荐答案

尝试类似:

((TextView) findViewById(R.id.textView2)).setText("");

尝试在 onCreate 之外创建一个变量，如 TextView text; 然后在 onCreate 内放置: text = (TextView)findViewById(R.id.textView2);

try making a variable outside the onCreate like TextView text; and then inside the onCreate put: text = (TextView) findViewById(R.id.textView2);

然后将 text.setText(""); 放在 onPostExecute 方法中.

and then just put text.setText(""); inside the onPostExecute method.

看看是否有效.

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