Question

我正在为我的大学开设一个项目。我的Android应用程序需要与服务器通信以发送命令并接收一些数据。我能够发送和接收数据。问题是当我想要将数据打印出volly类时，没有可用的接收数据。

final RequestQueue requestQueue = Volley.newRequestQueue(MainActivity.this);
        StringRequest stringRequest = new StringRequest(Request.Method.GET, server_url += "/?data="+ enteredUsername.getText().toString()+","+ enteredPassword.getText().toString()+","+enteredSiteId.getText().toString(),

            new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    returnFromServer =response.toString();
                    requestQueue.stop();
                }
            }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                commandStatus.setText("SERVER DOWN");
                error.printStackTrace();
                requestQueue.stop();
                }
            });
        requestQueue.add(stringRequest);
        commandStatus.setText(returnFromServer);//there is no value here out side the volly class
    }

我必须比较返回值表单服务器以供进一步使用。

Answer 1

在您的类中创建一个ResponseListener对象，如下所示：

Response.Listener<String> response = new Response.Listener<String>(){
    @Override
            public void onResponse(String response) {
                returnFromServer =response.toString();
                requestQueue.stop();
            }
};

然后将听众传递给凌空：

public void yourMethod(){
    ....
    callApi(response)
    ....
}

public void callAPI(Response.Listener<String> response) {
        StringRequest stringRequest = new StringRequest(Request.Method.GET, server_url += "/?data="+ enteredUsername.getText().toString()+","+ enteredPassword.getText().toString()+","+enteredSiteId.getText().toString(), 
        response, 
        new Response.ErrorListener(){...} 
}

<强>实施

public class MainActivity extends Activity{

    Response.Listener<String> response = new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                returnFromServer =response.toString();
                requestQueue.stop();
            }
        };

    private void callAPI(Response.Listener<String> respone) {
        final RequestQueue requestQueue = Volley.newRequestQueue(MainActivity.this);
    StringRequest stringRequest = new StringRequest(Request.Method.GET, server_url += "/?data="+ enteredUsername.getText().toString()+","+ enteredPassword.getText().toString()+","+enteredSiteId.getText().toString(),
       response,
    , new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            commandStatus.setText("SERVER DOWN");
            error.printStackTrace();
            requestQueue.stop();
            }
        });
        requestQueue.add(stringRequest);
        commandStatus.setText(returnFromServer);//there is no value here out side the volly class
        }
    }
}

只需在任何地方调用callAPI方法，并将响应作为参数传递。如果从服务器收到响应，则在MainActivity中调用onResponse方法。

在您调用API的同一个类中实现Response.Listener并在排序中将响应参数设置为this的另一种简单方法。

如何在volly类之外回复volly responserListner的响应

1 个答案: