如何调用web服务后显示警告 [英] how to show alert after calling the webservice

问题描述

在我的活动我打电话web服务。所以web服务返回结果后，我一定要显示一个警告。由于警报UI的部分，我觉得里面onPostExecute（）我有写的警报code。但是，当我做这样的错误来了。

In my activity I am calling webservices. So after the webservice returns the result, I have to show an alert. Since alert is UI part, I think inside onPostExecute() I have to write the alert code. But when I do like that error is coming.

显示错误：

12-02 09:59:08.508: ERROR/AndroidRuntime(451): Uncaught handler: thread main exiting 
due to uncaught exception
12-02 09:59:08.528: ERROR/AndroidRuntime(451): 
android.view.WindowManager$BadTokenException: Unable to add window -- token 
android.app.LocalActivityManager$LocalActivityRecord@4378eb50 is not valid; is your 
activity running?
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
android.view.ViewRoot.setView(ViewRoot.java:456)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
android.view.WindowManagerImpl.addView(WindowManagerImpl.java:177)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
android.view.Window$LocalWindowManager.addView(Window.java:409)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at
android.app.Dialog.show(Dialog.java:238)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
android.app.AlertDialog$Builder.show(AlertDialog.java:802)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at    com.myapp.android.activities.Register$PostCodeTask.onPostExecute(Register.java:291)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at     com.myapp.android.activities.Register$PostCodeTask.onPostExecute(Register.java:1)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at
android.os.AsyncTask.finish(AsyncTask.java:416) 
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
android.os.AsyncTask.access$300(AsyncTask.java:127)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:428)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
android.os.Handler.dispatchMessage(Handler.java:99)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
android.os.Looper.loop(Looper.java:123)
android.app.ActivityThread.main(ActivityThread.java:4203)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
java.lang.reflect.Method.invokeNative(Native Method)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
java.lang.reflect.Method.invoke(Method.java:521)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at 
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
12-02 09:59:08.528: ERROR/AndroidRuntime(451):     at dalvik.system.NativeStart.main(Native 
Method)

任何人都可以请帮助解决我的问题。在此先感谢：）

Can anyone please help to solve my issue. Thanks in advance :)

推荐答案

您需要UI线程来执行你的警觉code。这样做有它例如一些方法

You need to execute your alert code in UI thread. There are few ways of doing it for example

runOnUiThread(new Runnable() {
    public void run() {
        Toast.makeText(MyActivity.this, "Hello there", Toast.LENGTH_LONG).show();
    }
});

这篇关于如何调用web服务后显示警告的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！