您好我想打吐司可我没有就事论事什么，可从任何每当我想在我的应用程序线程。因此，要做到这一点，我延长了活动类：

Hi I want to make Toast available to me no-matter-what and available from any thread whenever I like within my application. So to do this I extended the Activity class:

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.widget.Toast;

public class MyActivity extends Activity{
    private Handler mHandler;

    @Override   
    public void onCreate(Bundle savedInstanceState) {       
        mHandler = new Handler();
        super.onCreate(savedInstanceState);
    }

    private class ToastRunnable implements Runnable {
        String mText;

        public ToastRunnable(String text) {
            mText = text;
        }

        public void run(){
           Toast.makeText(getApplicationContext(), mText, Toast.LENGTH_SHORT).show();
        }
    }

    public void doToast(String msg) {
        mHandler.post(new ToastRunnable(msg));
    }
}

让所有 活动班我的应用程序，现在只是

so that all Activity classes in my app are now simply

public class AppMain extends MyActivity {
   //blah
}

我希望能够做到（在辅助线程）是这样的：

what I expected to be able to do (in a worker thread) was this:

try{
   MyActivity me = (MyActivity) Looper.getMainLooper().getThread();
   me.doToast("Hello World");
}
catch (Exception ex){
   Log.e("oh dear", ex.getMessage());
}

和，只要活动是 MyActivity 它应该工作 - 但问题是 - - >在 Looper.getMainLooper（）getThread（）; 不是返回 MyActivity 来我和它的制作。我哭了 - 我究竟做错了什么？

and so long as the Activity was a "MyActivity" it should work - but the problem is ---> the Looper.getMainLooper().getThread(); isn't returning the MyActivity to me and it's making me cry - what am I doing wrong?

：编辑：

一些背景来解释为什么我坚持这种类型的implmentation的。

some background to explain "why" I am stuck with this type of implmentation.

我需要能够确认到，一个的HTTP POST事件已经是成功的用户。现在。如果用户点击确定就用户界面形式，它可能或不可能有互联网，在那个时候。如果它有互联网 - 一切都很好 - 这职位通过HTTP POST形式的一切都很好 ..但如果​​有否网络 Android的大多数（99.999％的应用服务跛脚/可怜/ mewling这个，基本上为用户提供无计划B假设在任何时候互联网是没有 - 当它不是）

I need to be able to confirm to the user that a "HTTP POST" event has been a success. Now. If the User clicks "OK" on the UI Form it MAY or MAY NOT have internet at that time.. If it has Internet - all well and good - it posts the form via HTTP POST all well and good.. but if there is NO Internet most (99.999% of Android apps lame /pathetic / mewling at this, and basically offer the user no plan "b" assuming that at all times the internet is there - when it is NOT)

我的应用程序不会跛脚走（我称之为）在后台无提示线索。我有足够的用户交互遍布应用程序，我不知道在哪里，用户将是，但最终在HTTP POST的队列/重/队列/重试回报！成功了！ 我想吐司，作为一个信息给用户（如：你的形式发送）

My App will not "go lame (as I call it)" - it does have a plan "b" instead it "Queues" the post event and retries every x minutes.. now this is a silent thread in the background.. I have plenty of user interaction all over the app I don't know where the user will "be" but eventually when the HTTP POST that queue/retries/queue/retries returns "! Success! " I want to Toast that as a message to the user (EG: "your form was sent")

推荐答案

有什么毛病 runOnUiThread ？

http://developer.android.com/reference/android/app/Activity.html#runOnUiThread(java.lang.Runnable)

activity.runOnUiThread(new Runnable() {
    public void run() {
        Toast.makeText(activity, "Hello, world!", Toast.LENGTH_SHORT).show();
    }
});