活动-> AsyncTask-> BroadcastReceiver->更新用户界面 [英] Activity -> AsyncTask -> BroadcastReceiver -> Update UI

问题描述

我正在从Activity开始AsyncTask.当AsyncTask完成执行时，我需要发送广播，该广播需要调用Activity方法来更新UI.

任何实现这一目标的好方法.

I am starting an AsyncTask from an Activity. When, the AsyncTask completes its execution I need to send a broadcast which needs to call Activity method to update the UI.

Any good approach to achieve this.

推荐答案

是.

如果AsyncTask是Activity的内部类，则它可以访问任何成员变量和Activity方法.如果不是，那么您可以简单地将变量传递给其构造函数，甚至可以传递对Activity的引用，以从onPostExecute()调用Activity方法.没有任何代码，很难说太多.

If the AsyncTask is an inner class of your Activity then it has access to any member variables and your Activity methods. If it isn't then you can simply pass variables to its constructor or even a reference to the Activity to call Activity methods from onPostExecute(). Without any code its hard to say much else.

要传递Activity的实例并使用其方法(如果它是单独的类)，则可以创建构造函数并执行类似的操作

To pass an instance of your Activity and use its methods if its a separate class then you can create a constructor and do something like

    public class MyTask extends AsyncTask<...>  // add your params
{
    private MyActivity activty;

    public MyTask (MyActivity act)
    {
        this.activty = activty;
    }

    // ...
}

，然后在onPostExecute()中添加类似内容

and in onPostExecute() add something like

activity.myMethod();

并像这样调用任务

MyTask task = new MyTask(this); // pass a reference of the activity
task.execute();  // add params if needed

如果AsyncTask是与Activity不同的文件，则可以

If the AsyncTask is a separate file from the Activity then you can see this answer on how to use an interface for a callback

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