Android Service extends ResultReceiver for IntentService，如何实现CREATOR？

Question

我的应用依赖于 Service，它在后台与外部硬件保持同步。因为该服务在 main 线程上运行，所以它使用 IntentService 异步执行任何繁重的工作。这是解释控制流的代码的最小化示例：

public class MyService extends Service {
  private final Handler handler = new Handler();

  void someMethodDoesCallBarAsynchronously(){
    Intent i = new Intent(this, MyIntentService.class);
    i.putAction(ACTION_FOO);
    i.putExtra(EXTRA_RECEIVER, new MyResultReceiver(handler));
    startService(toGetScannerStatus);
  }

  void receivedFooResult(String bar){
    //...
  }

  public class MyResultReceiver extends ResultReceiver{

    public MyResultReceiver(Handler handler){
      super(handler);
    }

    @Override
    protected void onReceiveResult(int resultCode, Bundle resultData) {
      super.onReceiveResult(resultCode, resultData);

      switch(resultCode){
        case RESULT_CODE_FOO:
          receivedFooResult(resultData.getString(FOO_RESULT));
        break;
      }
    }
  }
}

public class MyIntentService extends IntentService {

  public MyIntentService(){super("MyIntentService");}

  @Override
  protected void onHandleIntent(Intent intent) {
    switch (intent.getAction()) {
      case ACTION_FOO:
        ResultReceiver receiver = intent.getParcelableExtra(EXTRA_RECEIVER);
        Bundle bundle = new Bundle()
        bundle.putString(FOO_RESULT, foo());
        receiver.send(RESULT_CODE_FOO, b);
      break;
  }
}

现在，经过半年和一些更新，Android Studio 抱怨 MyResultReceiver 实现了 Parcelable 但不提供 CREATOR 字段。问题一，MyResultReceiver是一个内层的class，所以我得把它放到一个自己的class中。我不能使它 static 因为它必须包含对 MyService 的引用。那还是很简单的：

public class MyService extends Service {
  private final Handler handler = new Handler();

  void someMethodDoesCallBarAsynchronously(){
    Intent i = new Intent(this, MyIntentService.class);
    i.putAction(ACTION_FOO);
    i.putExtra(EXTRA_RECEIVER, new MyResultReceiver(this, handler));
    startService(toGetScannerStatus);
  }

  void receivedFooResult(String bar){
    //...
  }
}

public class MyResultReceiver extends ResultReceiver{
  private final MyService myService;

  public MyResultReceiver(MyService s, Handler handler){
    super(handler);
    this.myService = myService;
  }

  @Override
  protected void onReceiveResult(int resultCode, Bundle resultData) {
    super.onReceiveResult(resultCode, resultData);

    switch(resultCode){
      case RESULT_CODE_FOO:
        myService.receivedFooResult(resultData.getString(FOO_RESULT));
      break;
    }
  }
}

现在我可以添加一个 public 静态字段。但是如何正确实现CREATOR呢？

public class MyResultReceiver extends ResultReceiver {

  public static final Parcelable.Creator<MyResultReceiver> CREATOR
    = new Parcelable.Creator<MyResultReceiver>() {
        public MyResultReceiver[] newArray(int size) {
          return new MyResultReceiver[size];
        }
        public MyResultReceiver createFromParcel(Parcel in) {
          // ???
        }
      };

如果您想：为什么这是必要的？它会用来做什么？

Answer 1

恕我直言，您当前的架构太复杂了：您可以轻松地在一个 Service 中做到这一点，但是当涉及到您的问题时，这取决于您：您不需要创建任何 CREATOR 因为你得到的是一个 lint 警告，只需像这样添加 SuppressLint 注释：

@SuppressLint("ParcelCreator")
public class MyResultReceiver extends ResultReceiver {

Android Service extends ResultReceiver for IntentService，如何实现CREATOR？

Android Service extends ResultReceiver for IntentService, how to implement CREATOR?

android

android-service

intentservice

android-intentservice