Question

我是java / android开发的新手，所以请尽可能帮忙。

我想有一个从Web服务（异步）获取数据的方法，一旦完成（onSuccess或onFailure），它应该在活动类上调用另一个方法。让我说我有WebManager类，这不是真正的方法，我将添加更多仍然加上try / catch等等：

    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let说的getObject1（），当数据下载时我想调用方法：

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

创建界面

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

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
                }
            });
}

在您的活动中实施界面

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 }

}

同样，您可以为onFailure方法注册回调。

Answer 2

更好的方法可能是使用处理程序和消息。

http://developer.android.com/reference/android/os/Handler.html

或者至少不要忘记通过以下方式在UI线程中运行UI相关代码：

    runOnUiThread(new Runnable() {

        @Override
        public void run() {
            // code

        }
    });

从onSuccess到另一个类的调用方法

2 个答案: