Android/Java-异步任务完成时执行警报？

Question

当用户无法登录他们的帐户时，我正在尝试执行警报。也就是说，当我尝试使用下面的代码完成此操作时，我会抛出以下错误：

原因：java.lang.RuntimeException：无法在未调用Looper.prepare（）的线程[AsyncTask#1,5，main]内创建处理程序

我怎样才能解决这个问题？请参阅下面的代码。

登录活动

 private class MyNetwork extends AsyncTask<Void, Void, Void> {
       
      @Override
            protected Void doInBackground(Void... voids) {
    
                JSONObject jsonObject = new JSONObject();
                try {
                    jsonObject.put("username", "admin");
                    jsonObject.put("password", "test#5Q");
    
                } catch (JSONException e) {
                    e.printStackTrace();
                }
    
                OkHttpClient client = new OkHttpClient();
                MediaType JSON = MediaType.parse("application/json; charset=utf-8");
                // put your json here
                RequestBody body = RequestBody.create(JSON, jsonObject.toString());
                Request request = new Request.Builder()
                        .url("http://myurl.com/wp-json/wp/v2/custom-plugin/login")
                        .post(body)
                        .build();
    
                Response response = null;
                try {
                    response = client.newCall(request).execute();
                    String resStr = response.body().string();
                    Log.i("The response is", String.valueOf(response));
                    int responseCode = response.code();
                    Log.i("Check response code", String.valueOf(responseCode));
    
                    if (responseCode == 200) {
    
    
                        Log.i("We're logged in!", String.valueOf(responseCode));
    
                        Intent i = new Intent(LoginActivity.this, DashboardActivity.class);
                        startActivity(i);
    
    
                }
    
                    if (responseCode == 500) {
    
    
                        Log.i("User or pass incorrect.", String.valueOf(responseCode));
    
    
                        AlertDialog alertDialog = new AlertDialog.Builder(LoginActivity.this).create();
                        alertDialog.setTitle("Oops!");
                        alertDialog.setMessage("Your username or password is incorrect. Please check your credentials and try again.");
                       
                        alertDialog.setButton(AlertDialog.BUTTON_POSITIVE, "Ok", new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int which) {
                                Toast.makeText(getApplicationContext(), "You clicked on OK", Toast.LENGTH_SHORT).show();
                            }
                        });
    
    
                    }
    
                } catch (IOException e) {
                    e.printStackTrace();
    
                }
    
                return null;
            }

}

    public void launchDashboard (View v) {

       new MyNetwork().execute();

    }

Answer 1

我能够通过将我的AlertDialog包装在以下内容来修复上述错误：

 runOnUiThread(new Runnable() {
                        public void run() {

}