java Android，我可以将 AsyncTask 放在单独的类中并进行回调吗？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/10768449/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Android, can I put AsyncTask in a separate class and have a callback?
提问by Roger Travis
I'm just learning about AsyncTask and want to use it as a separate class, rather then a subclass.
我只是在学习 AsyncTask 并希望将它用作单独的类，而不是子类。
For example,
例如，
class inetloader extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... urls) {
String response = "";
DefaultHttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(urls[0]);
try {
HttpResponse execute = client.execute(httpGet);
InputStream content = execute.getEntity().getContent();
BufferedReader buffer = new BufferedReader(
new InputStreamReader(content));
String s = "";
while ((s = buffer.readLine()) != null) {
response += s;
}
} catch (Exception e) {
e.printStackTrace();
}
return response;
}
@Override
protected void onPostExecute(String result) {
Log.e("xx",result);
// how do I pass this result back to the thread, that created me?
}
}
and the main(ui) thread:
和主（ui）线程：
inetloader il = new inetloader();
il.execute("http://www.google.com");
//il.onResult()
//{
///do something...
//}
Thanks!
谢谢！
回答by Xi Zhang
Use a interface. Something like:
使用接口。就像是：
interface CallBackListener{
public void callback();
}
Then do this in your UI thread:
然后在您的 UI 线程中执行此操作：
inetloader il = new inetloader();
li.setListener(this);
il.execute("http://www.google.com");
In inetloader, add:
在 inetloader 中，添加：
CallBackListener mListener;
public void setListener(CallBackListener listener){
mListener = listener;
}
then In postExecute(), do:
然后在 postExecute() 中，执行：
mListener.callback();
回答by Dheeresh Singh
you can pass the activity instance to constructor and call activity function from there...
Like use interface :
您可以将活动实例传递给构造函数并从那里调用活动函数......
就像使用接口一样：
public interface ResultUpdatable {
public void setResult(Object obj);
}
Implement this in the Activity and pass in the constructor of Async task and update the result from onPostExecuteusing setResultfunction.
在 Activity 中实现它并传入异步任务的构造函数并更新onPostExecute使用setResult函数的结果。
回答by Samir Mangroliya
inetloader il = new inetloader();
il.execute("http://www.google.com");
String result = il.get();//put it in try-catch
^^^^^^^^
here you get result which is in onPostExecute(String result)
here you get result which is in onPostExecute(String result)
