已经调用了回调，为什么？

Question

我总是得到“错误：已经调用了回调。”何时未设置字段栏（doc.bar）（请参阅注释）。 我正在使用async.js，express和mongodb。

有人发现错误吗？我不。 我错了什么？

提前谢谢。

09-18 17:03:46.787 6429-6429/ir.homa E/AndroidRuntime: FATAL EXCEPTION: main
                                                   Process: ir.homa, PID: 6429
                                                   java.lang.RuntimeException: Unable to start activity ComponentInfo{ir.homa/ir.homa.HotelDetail}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
                                                       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
                                                       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
                                                       at android.app.ActivityThread.access$800(ActivityThread.java:144)
                                                       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
                                                       at android.os.Handler.dispatchMessage(Handler.java:102)
                                                       at android.os.Looper.loop(Looper.java:135)
                                                       at android.app.ActivityThread.main(ActivityThread.java:5221)
                                                       at java.lang.reflect.Method.invoke(Native Method)
                                                       at java.lang.reflect.Method.invoke(Method.java:372)
                                                       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
                                                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
                                                    Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
                                                       at ir.homa.HotelDetail.onCreate(HotelDetail.java:43)
                                                       at android.app.Activity.performCreate(Activity.java:5937)
                                                       at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
                                                       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
                                                       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360) 
                                                       at android.app.ActivityThread.access$800(ActivityThread.java:144) 
                                                       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278) 
                                                       at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                       at android.os.Looper.loop(Looper.java:135) 
                                                       at android.app.ActivityThread.main(ActivityThread.java:5221) 
                                                       at java.lang.reflect.Method.invoke(Native Method) 
                                                       at java.lang.reflect.Method.invoke(Method.java:372) 
                                                       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899) 
                                                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)