java - 从 onSuccess 调用方法到另一个类

Question

我是 java/android 开发新手，所以如果可以的话请提供帮助。

我想要一个从 Web 服务(异步)获取数据的方法，一旦完成(onSuccess 或 onFailure)，它应该调用 Activity 类上的另一个方法。假设我有 WebManager 类，这不是真正的方法，我将添加更多内容以及 try/catch 等:

    public class WebManager {

            public MyObject1 getObject1() {
                AsyncHttpClient client = new AsyncHttpClient();

                client.get(QUERY_URL,
                        new JsonHttpResponseHandler() {

                            @Override
                            public void onSuccess(JSONObject jsonObject) {

                                 //Call method on my Activity and pass jsonObject (in the other method I want to pass my custom object instead of json)
                            }

                            @Override
                            public void onFailure(int statusCode, Throwable throwable, JSONObject error) {

                                //Call method on my Activity and pass statusCode, throwable and error
                            }
                        });
            }

            public MyObject2 getObject2() {
                AsyncHttpClient client = new AsyncHttpClient();
                // The same as above
            }
        }

现在在我的 MainActivity 中，我想调用 getObject1()，当下载数据时，我想调用方法:

WebManager wm = new WebManager();
//... 


protected void onObject1DataDownload(JSONObject jsonObject) {
    //Do something with the data
}

protected void onObject2DataDownload(CUSTOMOBJECT obj) {
    //Do something with the data
}

我怎样才能实现这样的目标？提前致谢

Answer 1

1. 创建界面

   public interface ResponseListener {
   void onObject1DataDownload(JSONObject jsonObject);
   }
   

2. 将WebManager中的getObject1()方法更改为参数化方法，并调用回调方法。

   public class WebManager {
   public MyObject1 getObject1(ResponseListener listener) {
       AsyncHttpClient client = new AsyncHttpClient();
   
       client.get(QUERY_URL,
               new JsonHttpResponseHandler() {
   
                   @Override
                   public void onSuccess(JSONObject jsonObject) {
   
                        //here's the change
                        listener.onObject1DataDownload(jsonObject);
                   }
   
                   @Override
                   public void onFailure(int statusCode, Throwable throwable, JSONObject error) {
   
                       //Call method on my Activity and pass statusCode, throwable and error
                   }
               });
   }
   

3. 在您的 Activity 中实现界面

   public class MainActivity implements ResponseListener{
   
   public void someMethod() {
    WebManager wm = new WebManager(); 
    //pass the activity as the listener
    wm.getObject1(this);
   
   }
   protected void onObject1DataDownload(JSONObject jsonObject) { 
   //this method will be called }
   
   protected void onObject2DataDownload(CUSTOMOBJECT obj) { //Do something with the data }
   
   }
   

类似地，您可以为 onFailure 方法注册回调。