java - Spinner 无法填充来自 WebService 的数据

Question

我正在尝试通过 asynctask 方法从数据库中获取数据但是这个错误发生在我的代码中，我知道我在其他 Activity 中使用的相同代码并且一切正常。这是 Logcat

09-14 15:01:50.575: D/GestureDetector(16972): [Surface Touch Event] mSweepDown False, mLRSDCnt : -1 mTouchCnt : 2 mFalseSizeCnt:0
09-14 15:01:50.705: D/AbsListView(16972): Get MotionRecognitionManager
09-14 15:01:52.375: D/AndroidRuntime(16972): Shutting down VM
09-14 15:01:52.375: W/dalvikvm(16972): threadid=1: thread exiting with uncaught exception (group=0x40f522a0)
09-14 15:01:52.380: E/AndroidRuntime(16972): FATAL EXCEPTION: main
09-14 15:01:52.380: E/AndroidRuntime(16972): java.lang.NullPointerException
09-14 15:01:52.380: E/AndroidRuntime(16972):    at com.example.t.m.r.AddNewAttendActivity$GetClasses.onPostExecute(AddNewAttendActivity.java:218)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at com.example.t.m.r.AddNewAttendActivity$GetClasses.onPostExecute(AddNewAttendActivity.java:1)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at android.os.AsyncTask.finish(AsyncTask.java:631)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at android.os.AsyncTask.access$600(AsyncTask.java:177)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at android.os.Handler.dispatchMessage(Handler.java:99)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at android.os.Looper.loop(Looper.java:137)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at android.app.ActivityThread.main(ActivityThread.java:4898)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at java.lang.reflect.Method.invokeNative(Native Method)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at java.lang.reflect.Method.invoke(Method.java:511)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1008)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:775)
09-14 15:01:52.380: E/AndroidRuntime(16972):    at dalvik.system.NativeStart.main(Native Method)

Answer 1

你有没有在onPostExecute中初始化Spinner？

在第 218 行之前 spin_class.setAdapter(adapter1);

你必须在 onPostExecute 中初始化它，因为你在 AsycnTask 中，它不是主线程!