我正在使用SQLite数据库,每当我调用它时,我都需要将上下文传递给它.我通常使用getApplicationContext()来执行此操作,该工作在其他活动中.在我当前的类中,它只返回null.救命!
04-06 16:46:19.523: E/AndroidRuntime(4279): Process: com.example.schoolandrevisiontimetable, PID: 4279
04-06 16:46:19.523: E/AndroidRuntime(4279): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.schoolandrevisiontimetable/com.example.schoolandrevisiontimetable.Input_slessontime}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.Context android.content.Context.getApplicationContext()' on a null object reference
04-06 16:46:19.523: E/AndroidRuntime(4279): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2225)
04-06 16:46:19.523: E/AndroidRuntime(4279): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2388)
04-06 16:46:19.523: E/AndroidRuntime(4279): at android.app.ActivityThread.access$800(ActivityThread.java:148)
04-06 16:46:19.523: E/AndroidRuntime(4279): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1292)
04-06 16:46:19.523: E/AndroidRuntime(4279): at android.os.Handler.dispatchMessage(Handler.java:102)
04-06 16:46:19.523: E/AndroidRuntime(4279): at android.os.Looper.loop(Looper.java:135)
04-06 16:46:19.523: E/AndroidRuntime(4279): at android.app.ActivityThread.main(ActivityThread.java:5312)
04-06 16:46:19.523: E/AndroidRuntime(4279): at java.lang.reflect.Method.invoke(Native Method)
04-06 16:46:19.523: E/AndroidRuntime(4279): at java.lang.reflect.Method.invoke(Method.java:372)
04-06 16:46:19.523: E/AndroidRuntime(4279): at …