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WebView에서 loadUrl하는 도중에 NullPointException 이발생합니다.

0 추천

학교 기말고사때문에 어플을 제작중입니다...

군전역후 엇학기로 복학하는바람에 자바를 제대로 배우지않고 안드로이드 어플을 만드려니 쉽진 않네요 ㅠ 

 

다름이아니라 Main페이지의 TabView에 있는 Button 클릭시 새로운 TabView를 가진 xml을 띄우려고합니다.

어느정도 구현은 했는데 두번째 탭뷰에 진입하여 탭을 전환하는 도중에 NullPointerException 에러가 뜨네요 ㅠㅠ MainActivity -> 3개의 SubActivity(탭이 3개입니다) -> Sub_Activity -> 4개의 subActivity로 구성되어있습니다.

SubActivity1 이구요 (2,3은 아직 미구현입니다..)

SubActivity에 있는 버튼 클릭시 문자열을 intent로 다른 액티비티로 넘겨줍니다.

그러고나서 또한번 하위 Activity로 문자열을 넘겨주게됩니다.

이렇게 넘겨진 문자열을 검사하여 상황에 맞는 html파일을 로드하고있는데, 

어플 실행후 버튼클릭->새로운 레이아웃 로드-> 첫 탭전환 은 정상적으로 동작합니다. 

하지만 탭전환을 2회 혹은 3회 하게되면 앱이 중지되며 아래 사진  loadUrl 부분에서 NullPoint Exception 에러가 발생합니다... ㅠ 

 

도움 부탁드리겠습니다...

익명사용자 님이 2017년 11월 28일 질문

1개의 답변

0 추천

NullPointerException에 대한 로그를 보여주세요.

 
minor (13,710 포인트) 님이 2017년 11월 29일 답변
11-29 12:41:19.673 22559-22559/com.example.hanch.digital_contents E/AndroidRuntime: FATAL EXCEPTION: main
                                                                                    Process: com.example.hanch.digital_contents, PID: 22559
                                                                                    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.hanch.digital_contents/com.example.hanch.digital_contents.ski_3}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.webkit.WebView.loadUrl(java.lang.String)' on a null object reference
                                                                                        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646)
                                                                                        at android.app.ActivityThread.startActivityNow(ActivityThread.java:2446)
                                                                                        at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:136)
                                                                                        at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:348)
                                                                                        at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:724)
                                                                                        at android.widget.TabHost.setCurrentTab(TabHost.java:388)
                                                                                        at android.widget.TabHost$2.onTabSelectionChanged(TabHost.java:158)
                                                                                        at android.widget.TabWidget$TabClickListener.onClick(TabWidget.java:532)
                                                                                        at android.view.View.performClick(View.java:5610)
                                                                                        at android.view.View$PerformClick.run(View.java:22265)
                                                                                        at android.os.Handler.handleCallback(Handler.java:751)
                                                                                        at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                                        at android.os.Looper.loop(Looper.java:154)
                                                                                        at android.app.ActivityThread.main(ActivityThread.java:6077)
                                                                                        at java.lang.reflect.Method.invoke(Native Method)
                                                                                        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
                                                                                        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)
                                                                                     Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.webkit.WebView.loadUrl(java.lang.String)' on a null object reference
                                                                                        at com.example.hanch.digital_contents.ski_3.onCreate(ski_3.java:36)
                                                                                        at android.app.Activity.performCreate(Activity.java:6662)
                                                                                        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
                                                                                        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599)
                                                                                        at android.app.ActivityThread.startActivityNow(ActivityThread.java:2446) 
                                                                                        at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:136) 
                                                                                        at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:348) 
                                                                                        at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:724) 
                                                                                        at android.widget.TabHost.setCurrentTab(TabHost.java:388) 
                                                                                        at android.widget.TabHost$2.onTabSelectionChanged(TabHost.java:158) 
                                                                                        at android.widget.TabWidget$TabClickListener.onClick(TabWidget.java:532) 
                                                                                        at android.view.View.performClick(View.java:5610) 
                                                                                        at android.view.View$PerformClick.run(View.java:22265) 
                                                                                        at android.os.Handler.handleCallback(Handler.java:751) 
                                                                                        at android.os.Handler.dispatchMessage(Handler.java:95) 
                                                                                        at android.os.Looper.loop(Looper.java:154) 
                                                                                        at android.app.ActivityThread.main(ActivityThread.java:6077) 
                                                                                        at java.lang.reflect.Method.invoke(Native Method) 
                                                                                        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866) 
                                                                                        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756) 


라고 뜨네요.... loadUrl부분에서 NullPointException 에러가 뜨는것같습니다..
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