Android中使用数据库进行数据插入时提示unfortunately

log
11-24 02:08:21.050: D/gralloc_goldfish(1394): Emulator without GPU emulation detected.
11-24 02:09:06.610: W/dalvikvm(1394): threadid=1: thread exiting with uncaught exception (group=0xb4a5bb90)
11-24 02:09:06.700: E/AndroidRuntime(1394): FATAL EXCEPTION: main
11-24 02:09:06.700: E/AndroidRuntime(1394): Process: ui.cqupt, PID: 1394
11-24 02:09:06.700: E/AndroidRuntime(1394): java.lang.NullPointerException
11-24 02:09:06.700: E/AndroidRuntime(1394): at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:224)
11-24 02:09:06.700: E/AndroidRuntime(1394): at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:164)
11-24 02:09:06.700: E/AndroidRuntime(1394): at db.cquupt.DBconnection.getConnection(DBconnection.java:39)
11-24 02:09:06.700: E/AndroidRuntime(1394): at model.cqupt.BookList.getBookList(BookList.java:25)
11-24 02:09:06.700: E/AndroidRuntime(1394): at control.cqupt.Contol.addBook(Contol.java:8)
11-24 02:09:06.700: E/AndroidRuntime(1394): at ui.cqupt.InsertActivity$ButtonListener.onClick(InsertActivity.java:43)
11-24 02:09:06.700: E/AndroidRuntime(1394): at android.view.View.performClick(View.java:4424)
11-24 02:09:06.700: E/AndroidRuntime(1394): at android.view.View$PerformClick.run(View.java:18383)
11-24 02:09:06.700: E/AndroidRuntime(1394): at android.os.Handler.handleCallback(Handler.java:733)
11-24 02:09:06.700: E/AndroidRuntime(1394): at android.os.Handler.dispatchMessage(Handler.java:95)
11-24 02:09:06.700: E/AndroidRuntime(1394): at android.os.Looper.loop(Looper.java:137)
11-24 02:09:06.700: E/AndroidRuntime(1394): at android.app.ActivityThread.main(ActivityThread.java:4998)
11-24 02:09:06.700: E/AndroidRuntime(1394): at java.lang.reflect.Method.invokeNative(Native Method)
11-24 02:09:06.700: E/AndroidRuntime(1394): at java.lang.reflect.Method.invoke(Method.java:515)
11-24 02:09:06.700: E/AndroidRuntime(1394): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
11-24 02:09:06.700: E/AndroidRuntime(1394): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
11-24 02:09:06.700: E/AndroidRuntime(1394): at dalvik.system.NativeStart.main(Native Method)

空指针异常 应该是在你代码 BookList的第25行 应该是

感觉数据库助手类没使用对啊

问题以及解决啦,没有在代码中添加连接数据库函数