我正在使用Smack构建一个应用程序.在Eclipse模拟器中运行app后,apk安装成功,但似乎没有响应.点击它后,我收到警报"不幸的是,应用程序停止工作".请帮我解决一下.Logcat:
01-13 05:55:17.117: E/AndroidRuntime(1067): FATAL EXCEPTION: main
01-13 05:55:17.117: E/AndroidRuntime(1067): Process: com.demo.xmppchat, PID: 1067
01-13 05:55:17.117: E/AndroidRuntime(1067): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.demo.xmppchat/com.demo.xmppchat.CustomizedListView}: java.lang.NullPointerException
01-13 05:55:17.117: E/AndroidRuntime(1067): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2176)
01-13 05:55:17.117: E/AndroidRuntime(1067): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2226)
01-13 05:55:17.117: E/AndroidRuntime(1067): at android.app.ActivityThread.access$700(ActivityThread.java:135)
01-13 05:55:17.117: E/AndroidRuntime(1067): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1397)
01-13 05:55:17.117: E/AndroidRuntime(1067): at android.os.Handler.dispatchMessage(Handler.java:102)
01-13 05:55:17.117: E/AndroidRuntime(1067): at android.os.Looper.loop(Looper.java:137)
01-13 05:55:17.117: E/AndroidRuntime(1067): at android.app.ActivityThread.main(ActivityThread.java:4998)
01-13 05:55:17.117: E/AndroidRuntime(1067): at java.lang.reflect.Method.invokeNative(Native Method)
01-13 05:55:17.117: E/AndroidRuntime(1067): at java.lang.reflect.Method.invoke(Method.java:515)
01-13 05:55:17.117: E/AndroidRuntime(1067): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
01-13 05:55:17.117: E/AndroidRuntime(1067): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593) …Run Code Online (Sandbox Code Playgroud) 我正在使用xmpp和smack api在android中编写聊天应用程序.当我输入特定朋友的电子邮件ID发送聊天时聊天工作成功.但是我无法获得离线/在线用户列表.请建议如何使用xmpp smack获取用户列表..?