请帮我解决错误:
D/AndroidRuntime(836): Shutting down VM
W/dalvikvm(836): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
E/AndroidRuntime(836): FATAL EXCEPTION: main
E/AndroidRuntime(836): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.FirstProject/com.example.FirstProject.List}: java.lang.IllegalStateException: getWritableDatabase called recursively
E/AndroidRuntime(836): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
E/AndroidRuntime(836): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
E/AndroidRuntime(836): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
E/AndroidRuntime(836): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
E/AndroidRuntime(836): at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime(836): at android.os.Looper.loop(Looper.java:123)
E/AndroidRuntime(836): at android.app.ActivityThread.main(ActivityThread.java:4627)
E/AndroidRuntime(836): at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime(836): at java.lang.reflect.Method.invoke(Method.java:521)
E/AndroidRuntime(836): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
E/AndroidRuntime(836): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
E/AndroidRuntime(836): at dalvik.system.NativeStart.main(Native Method)
E/AndroidRuntime(836): Caused by: java.lang.IllegalStateException: getWritableDatabase called recursively
E/AndroidRuntime(836): at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:81)
E/AndroidRuntime(836): at com.example.FirstProject.Database.onCreate(Database.java:36)
E/AndroidRuntime(836): …