android - 调用 postExecute 时在 AsyncTask 中添加监听器

Question

我有一个 AsyncTask 类。

这是代码。

private class WaitSec extends AsyncTask<Void, Void, Boolean>{
    @Override
    protected Boolean doInBackground(Void... params) {
        try {
            Thread.sleep(2000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        if(CheckSomeUtil.isItOk()) {
            return true;
        } else {
            return false;
        }
    }
    @Override
    protected void onPostExecute(Boolean aBoolean) {
        if(aBoolean)
            // in this line. is i want to set listener.
        super.onPostExecute(aBoolean);
    }
}

当调用 onPostExecute 方法时，我想在 Activity 中获取 bool 值。

谢谢。

Answer 1

您需要使用回调引用，然后通过它传递信息。

private class WaitSec extends AsyncTask<Void, Void, Boolean>{
public AsyncTaskCallback callback = null;

public WaitSec(AsyncTaskCallback callback){
        this.callback = callback;
}

@Override
protected Boolean doInBackground(Void... params) {
    try {
        Thread.sleep(2000);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }

    if(CheckSomeUtil.isItOk()) {
        return true;
    } else {
        return false;
    }
}
@Override
protected void onPostExecute(Boolean aBoolean) {
    if(aBoolean)
        // in this line. is i want to set listener.
      if(callback != null) {
          callback.onPostExecute(aBoolean);
      }
    super.onPostExecute(aBoolean);
}

public interface AsyncTaskCallback {
        void onPostExecute(Boolean aBoolean);
}
}

Your Activity.java

public class YourActivity implements AsyncTaskCallback{
   private WaitSec asyncTask;

  @Override
  public void onCreate(Bundle savedInstanceState) {
    asyncTask  = new WaitSec(this);
    asyncTask.execute();
  }

  void onPostExecute(Boolean aBoolean){
     // get the boolean here and do what ever you want.
  }
}