如何返回从ASYN调用结果 [英] how to return result from asyn call

问题描述

我在自己的班级我所有的异步调用，所以我不想有全局变量被设置aync'ly。要做到这一点，我想返回对象如：从我的后处理asunc方法的字符串。

可以这样做？

下面是我的总体结构，以我的班，我想从onPostExecute返回一个字符串，例如（）。我看到代表们在其他地方提到但这似乎很凌乱，肯定有办法有一个返回类型的类或方法？

 类GetStuffAsyncly扩展的AsyncTask＆LT;字符串，字符串，字符串＆GT;
{
    //我瓦尔....    公共myconstructor（字符串dialogMessage，上下文CON）
    {
        this.qDialog =新ProgressDialog（CON）;
        this.dialogString = dialogMessage;
        this.context = CON;
    }    / **
     *启动后台线程显示进度对话框之前
     * * /
    @覆盖
    在preExecute保护无效（）
    {
        super.on preExecute（）;
        做的东西像火对话框
    }    @覆盖
    保护字符串doInBackground（字符串参数... args）
    {
       //做的东西在后台...        返回的数据;
    }    / **
     *在完成后台任务之后辞退进度对话框
     * ** /
    保护无效onPostExecute（字符串jsonString）
    {
        //关闭该对话框获取所有数据后，
        dialog.dismiss（）;
    }
}
 

解决方案

有些东西像下面

 类GetStuffAsyncly扩展的AsyncTask＆LT;字符串，字符串，字符串＆GT; {
    串dialogString;
    ProgressDialog对话框;
    上下文语境;
    AsyncListener监听;
    //我瓦尔....    公共GetStuffAsyncly（字符串dialogMessage，上下文CON，AsyncListener听众）{
        this.dialog =新ProgressDialog（CON）;
        this.dialogString = dialogMessage;
        this.context = CON;
        this.listener =侦听器;
    }    / **
     *启动后台线程显示进度对话框之前
     * /
    @覆盖
    在preExecute保护无效（）{
        super.on preExecute（）;
        listener.onTaskStarted（）;
    }    @覆盖
    保护字符串doInBackground（字符串参数... args）{
        //做的东西在后台...        返回的数据;
    }    / **
     *在完成后台任务之后辞退进度对话框
     ** /
    保护无效onPostExecute（字符串jsonString）{
        //关闭该对话框获取所有数据后，
        dialog.dismiss（）;
        listener.onTaskFinished（jsonString）;
    }
}
 

和监听器类

 公共接口AsyncListener {
    无效onTaskStarted（）;    无效onTaskFinished（字符串数据）;
}
 

和你可以调用像这样

 新GetStuffAsyncly（消息，对此，新AsyncListener（）{
            @覆盖
            公共无效onTaskStarted（）{
                //做你的东西
            }            @覆盖
            公共无效onTaskFinished（字符串数据）{
//做你的东西;
            }
        }）执行（参数）;
 

i have all my async calls in their own classes and so i dont want to have global vars being set aync'ly. To do this i want to return objects eg a string from my asunc postProcess methods.

can this be done?

Below is my general structure to my classes, i want to return a String for example from onPostExecute(). I see delegates are mentioned in other places but this seems very messy, sure there is a way to have a return type to the class or methods?

class GetStuffAsyncly extends AsyncTask<String, String, String>
{
    // my vars....

    public myconstructor(String dialogMessage, Context con)
    {
        this.qDialog =  new ProgressDialog(con);
        this.dialogString = dialogMessage;
        this.context = con;
    }

    /**
     * Before starting background thread Show Progress Dialog
     * */
    @Override
    protected void onPreExecute()
    {
        super.onPreExecute();
        do stuff like fire dialog
    }

    @Override
    protected String doInBackground(String... args)
    {
       // do stuff in background...

        return data;
    }

    /**
     * After completing background task Dismiss the progress dialog
     * **/
    protected void onPostExecute(String jsonString)
    {
        // dismiss the dialog after getting all data
        dialog.dismiss();
    }
}

解决方案

Some thing like below

class GetStuffAsyncly extends AsyncTask<String, String, String> {
    String dialogString;
    ProgressDialog dialog;
    Context context;
    AsyncListener listener;
    // my vars....

    public GetStuffAsyncly(String dialogMessage, Context con, AsyncListener listener) {
        this.dialog = new ProgressDialog(con);
        this.dialogString = dialogMessage;
        this.context = con;
        this.listener = listener;
    }

    /**
     * Before starting background thread Show Progress Dialog
     */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        listener.onTaskStarted();
    }

    @Override
    protected String doInBackground(String... args) {
        // do stuff in background...

        return data;
    }

    /**
     * After completing background task Dismiss the progress dialog
     **/
    protected void onPostExecute(String jsonString) {
        // dismiss the dialog after getting all data
        dialog.dismiss();
        listener.onTaskFinished(jsonString);
    }
}

And the listener class

public interface AsyncListener {
    void onTaskStarted();

    void onTaskFinished(String data);
}

and you can call like this

new GetStuffAsyncly(message, this, new AsyncListener() {
            @Override
            public void onTaskStarted() {
                //do your stuff
            }

            @Override
            public void onTaskFinished(String data) {
//Do your stuff;
            }
        }).execute(parameter);

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