机器人：从另一个类另一个线程更新界面 [英] android: update UI from another thread in another class

问题描述

该方案是
我有两个线程和UI线程。在登录按钮按下时，UI线程创建它创建了一个套接字，并运行，直到套接字连接的ClientThread，每当收到消息我使用一个处理程序发布消息，称为ProcessDataThread另一个线程，现在从服务器，我需要接受一些消息从ProcessDataThread更新UI相关的东西，我四处搜寻了很多，我发现这两种方式runonUiThread功能，我想只能从活动类，这是无用和AsyncTask的方法，我不知道如何将活动范围内传递到运行...

下面是code

在MainActivity上的登录按钮被点击时执行的code

 公共无效onLoginClick（查看视图）
{
    global_constants.clientObject =新ClientThread（）;
    global_constants.clientThread =新主题（global_constants.clientObject）;
    global_constants.clientThread.start（）;
}
 

的code在ClientThread run方法

 公共类ClientThread实现Runnable {
.......
    @覆盖
    公共无效的run（）{
    ......
        而（Thread.currentThread（）isInterrupted（）及！＆放大器;！（CloseThread））
        {
            字节[]的buff;
            ....
            global_constants.updateConversationHandler.post（新ProcessDataThread（BUFF））;
        }
    }
}
 

的方法code在ProcessDataThread解析出传入的数据和填充后

 公共类ProcessDataThread实现Runnable {
.........
    无效ProcessLoginFailedPacket（字节[] BUFF）
    {
        //如何从这里调用UI线程更新一些UI元素？
    }
}
 

我存储在一个全局变量的活动环境，然后就是这么做的，但我不知道它是否会更安全与否

 （（活动）global_constants.MainContext）.runOnUiThread（新的Runnable（）{
    公共无效的run（）
    {
        TextView的txtErr =（TextView中）（（活动）global_constants.MainContext）.findViewById（R.id.errMsg）;
        txtErr.setVisibility（0）;
        txtErr.setText（原因）;
    }
}）;
 

解决方案

您可以发布一个可运行由它来完成的UI操作主线程如下，

 公共类utils的{    公共静态无效runOnUiThread（Runnable接口可运行）{
        最后的处理程序UIHandler =新的处理程序（Looper.getMainLooper（））;
        UIHandler。员额（可运行）;
    }
}Utils.runOnUiThread（新的Runnable（）{
     @覆盖
     公共无效的run（）{
         // UI相关的选择更新code。
     }
}）;
 

The scenario is I have two threads and a UI thread. The UI thread when clicked on login button creates a ClientThread which creates a socket and runs until the socket is connected, whenever a message is received i use a handler to post message to another thread called ProcessDataThread, now on receiving some messages from server i need to update UI related stuff from ProcessDataThread, I searched around alot and i found these two ways runonUiThread function which i guess can only be run from the Activity Class which is useless and the Asynctask method which i am not sure how to pass the activity context to...

Here is the code

The code executed when clicked on Login Button in the MainActivity

public void onLoginClick(View view)
{
    global_constants.clientObject = new ClientThread();
    global_constants.clientThread = new Thread(global_constants.clientObject);
    global_constants.clientThread.start();
}

The code in ClientThread run method

public class ClientThread implements Runnable {
.......
    @Override
    public void run() {
    ......
        while(!Thread.currentThread().isInterrupted() && (!CloseThread))
        {
            byte[] buff;
            ....
            global_constants.updateConversationHandler.post(new ProcessDataThread(buff));
        }
    }
}

The method code in ProcessDataThread after parsing out the incoming data and stuff

public class ProcessDataThread implements Runnable {
.........
    void ProcessLoginFailedPacket(byte[] buff)
    {
        // how to call the UI thread from here for updating some UI elements??
    }
}

[EDIT]

i stored the activity context in a global variable and then did it this way, but i dont know whether it will be safer or not

((Activity)global_constants.MainContext).runOnUiThread(new Runnable(){
    public void run()
    {
        TextView txtErr = (TextView) ((Activity)global_constants.MainContext).findViewById(R.id.errMsg);
        txtErr.setVisibility(0);
        txtErr.setText(reason);
    } 
});

解决方案

You can post a runnable which does the UI operation to main thread as follows,

public class Utils {

    public static void runOnUiThread(Runnable runnable){
        final Handler UIHandler = new Handler(Looper.getMainLooper());
        UIHandler .post(runnable);
    } 
}

Utils.runOnUiThread(new Runnable() {
     @Override
     public void run() {
         // UI updation related code.
     }
});

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