我正在开发一个 Android 应用程序,我有AsynTask
这个Fragment
:
private class SendUserDatasAsynTask extends AsyncTask<User, Void, String>
{
private Context mContext;
private ProgressDialog loadingDialog;
SendUserDatasAsynTask(Context context)
{
this.mContext = context;
}
@Override
protected void onPreExecute()
{
loadingDialog = new ProgressDialog(mContext);
loadingDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
loadingDialog.setMessage(getString(R.string.dialog_message_sending_user_data));
loadingDialog.setCancelable(false);
loadingDialog.show();
super.onPreExecute();
}
@Override
protected String doInBackground(User... users)
{
return SpringController.sendUserPersonalData(users[0]);
}
protected void onPostExecute(String result)
{
loadingDialog.dismiss();
Toast.makeText(MSDApplication.getAppContext(), result, Toast.LENGTH_LONG).show();
}
}
但是当我execute
完成任务时,我收到了这个错误:
06-21 13:52:42.559: E/AndroidRuntime(513): Caused by: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application
at android.view.ViewRoot.setView(ViewRoot.java:509)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:177)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91)
at android.app.Dialog.show(Dialog.java:241)
at com.mycompany.mxt.fragments.UserProfileFragment$SendUserDatasAsynTask.onPreExecute(UserProfileFragment.java:635)
at android.os.AsyncTask.execute(AsyncTask.java:391)
at com.mycompany.mxt.fragments.UserProfileFragment.sendDataToWebService(UserProfileFragment.java:588)
at com.mycompany.mxt.fragments.UserProfileFragment.onAcceptUserProfileClick(UserProfileFragment.java:477)
你知道发生了什么吗?