java - Android Volley 抽象 onResponse

Question

我有两个类，它们将使用一个调用 Volley 并重写 onResponse 的类。除了两行之外，onReponse 中的代码将完全相同。基本上在响应上调用 super 但仍然执行额外的两行的最佳方法是什么？这就是我的意思:

Class A {
   ....
   Uploader uploader = new Uploader();
   uploader.startUpload(context, path, data);

   // I know this can't be done but showing what I want
   uploader.onResponse(String response) {
      super(response);
      ... 
      call to extra code
   } 
}  

B 类相同，但额外代码不同

public class Uploader implements Response.Listener<String> {
    public Uploader() { }

    public void upLoad(final Context context, String path, String data) {
        .... build request and then make call to start request
    }

    @Override
    public void onResponse(String response) {
        ... Doing something common for both A and B Classes
    }
}

Answer 1

您可以提取一个抽象类:

abstract class MyReponseListener implements Response.Listener<String> {

    @Override
    public void onResponse(String response) {
        //the two lines of common code you want 
    }
}

并让你的 Uploader扩展您的摘要MyResponseListener :

class Uploader extends MyResponseListener {
    public Uploader() { }

    public void upLoad(final Context context, String path, String data) {

    }

    @Override
    public void onResponse(String response) {
        super(response);
    }
}

如果您希望 Uploader 的消费者有不同的行为然后，您可以提供子类作为依赖项，如下所示。

重构ClassA依赖 Uploader :

public ClassA(Uploader uploader) {
    this.uploader = uploader;
}

子类化 Uploader :

Uploader classAUploader = new Uploader() { 
    @Override
    public void onResponse(String response) {
        super.onResponse(response);
        //your code for the special handling in ClassA
    }
};

将其作为 ClassA 的依赖项传递:

ClassA classA = new ClassA(classAUploader);

更好的解决方案可能使用组合而不是继承。所以Uploader 有 Response.Listener<String>而不是是 Response.Listener<String> 。那么不同的Response.Listener<String>可以作为 uploader 的依赖项传入，如上所述。如果您使用此技术，则不需要子类 Uploader只是为了改变 Response.Listener 的行为.