android - java.lang.IllegalArgumentException : View not attached to window manager

Question

我有一个启动 AsyncTask 并在操作期间显示进度对话框的 Activity 。声明该 Activity 不会通过旋转或键盘滑动重新创建。

    <activity android:name=".MyActivity" 
              android:label="@string/app_name"
              android:configChanges="keyboardHidden|orientation"
              >
        <intent-filter>
        </intent-filter>
    </activity>

任务完成后，我会关闭对话框，但在某些手机(框架:1.5、1.6)上会抛出此类错误:

java.lang.IllegalArgumentException: View not attached to window manager
    at android.view.WindowManagerImpl.findViewLocked(WindowManagerImpl.java:356)
    at android.view.WindowManagerImpl.removeView(WindowManagerImpl.java:201)
    at android.view.Window$LocalWindowManager.removeView(Window.java:400)
    at android.app.Dialog.dismissDialog(Dialog.java:268)
    at android.app.Dialog.access$000(Dialog.java:69)
    at android.app.Dialog$1.run(Dialog.java:103)
    at android.app.Dialog.dismiss(Dialog.java:252)
    at xxx.onPostExecute(xxx$1.java:xxx)

我的代码是:

final Dialog dialog = new AlertDialog.Builder(context)
    .setTitle("Processing...")
    .setCancelable(true)
    .create();

final AsyncTask<MyParams, Object, MyResult> task = new AsyncTask<MyParams, Object, MyResult>() {

    @Override
    protected MyResult doInBackground(MyParams... params) {
        // Long operation goes here
    }

    @Override
    protected void onPostExecute(MyResult result) {
        dialog.dismiss();
        onCompletion(result);
    }
};

task.execute(...);

dialog.setOnCancelListener(new OnCancelListener() {
    @Override
    public void onCancel(DialogInterface arg0) {
        task.cancel(false);
    }
});

dialog.show();

根据我阅读的内容 (http://bend-ing.blogspot.com/2008/11/properly-handle-progress-dialog-in.html) 并在 Android 源代码中看到，似乎唯一可能出现该异常的情况是 Activity 被破坏时。但正如我所提到的，我禁止为基本事件进行 Activity 娱乐。

所以任何建议都非常感谢。

Answer 1

当我从 onPostExecute 方法关闭对话框并完成 Activity 时，有时也会收到此错误。我想有时 Activity 会在对话框成功关闭之前完成。

适合我的简单而有效的解决方案

@Override
protected void onPostExecute(MyResult result) {
    try {
        if ((this.mDialog != null) && this.mDialog.isShowing()) {
            this.mDialog.dismiss();
        }
    } catch (final IllegalArgumentException e) {
        // Handle or log or ignore
    } catch (final Exception e) {
        // Handle or log or ignore
    } finally {
        this.mDialog = null;
    }  
}