java.lang.IllegalStateException : 이미 추가 된 조각 : NamedFragment

Question

많은 분들께서이 문제가 발생하기를 바랍니다. 시나리오는 매우 간단합니다. ViewPager에 대해 하나의 활동 만 있습니다. ViewPager에서 두 개의 프래그먼트 또는 로직을 기반으로 한 프래그먼트를 표시해야합니다. 따라서 FragmentPagerAdapter에서 ViewPagerAdapter를 만들고 조건에 조각베이스를 동적으로 추가했습니다. 그러나 작동하지 않고 오류가 발생했습니다.

java.lang.IllegalStateException: Fragment already added: NamedFragment{2c7b548 #0 id=0x7f0e0097 android:switcher:2131624087:0} 
                      at android.support.v4.app.FragmentManagerImpl.addFragment(FragmentManager.java:1669) 
                      at android.support.v4.app.BackStackRecord.executeOps(BackStackRecord.java:720) 
                      at android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2303) 
                      at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2132) 
                      at android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2092) 
                      at android.support.v4.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:1969) 
                      at android.support.v4.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:620) 
                      at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:143) 
                      at android.support.v4.view.ViewPager.populate(ViewPager.java:1268) 
                      at android.support.v4.view.ViewPager.populate(ViewPager.java:1116) 
                      at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1642) 
                      at android.view.View.measure(View.java:18805) 
                      at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:716) 
                      at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:462) 
                      at android.view.View.measure(View.java:18805) 
                      at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:716) 
                      at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:462) 
                      at android.view.View.measure(View.java:18805) 
                      at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
                      at android.widget.FrameLayout.onMeasure(FrameLayout.java:194) 
                      at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:139) 
                      at android.view.View.measure(View.java:18805) 
                      at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
                      at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465) 
                      at android.widget.LinearLayout.measureVertical(LinearLayout.java:748) 
                      at android.widget.LinearLayout.onMeasure(LinearLayout.java:630) 
                      at android.view.View.measure(View.java:18805) 
                      at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
                      at android.widget.FrameLayout.onMeasure(FrameLayout.java:194) 
                      at android.view.View.measure(View.java:18805) 
                      at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
                      at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465) 
                      at android.widget.LinearLayout.measureVertical(LinearLayout.java:748) 
                      at android.widget.LinearLayout.onMeasure(LinearLayout.java:630) 
                      at android.view.View.measure(View.java:18805) 
                      at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
                      at android.widget.FrameLayout.onMeasure(FrameLayout.java:194) 
                      at com.android.internal.policy.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2643) 
                      at android.view.View.measure(View.java:18805) 
                      at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2100) 
                      at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1216) 
                      at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1452) 
                      at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1107) 
                      at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6013) 
                      at android.view.Choreographer$CallbackRecord.run(Choreographer.java:858) 
                      at android.view.Choreographer.doCallbacks(Choreographer.java:670) 
                      at android.view.Choreographer.doFrame(Choreographer.java:606) 
                      at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844) 
                      at android.os.Handler.handleCallback(Handler.java:739) 
                      at android.os.Handler.dispatchMessage(Handler.java:95) 
                      at android.os.Looper.loop(Looper.java:148) 
                      at android.app.ActivityThread.main(ActivityThread.java:5417) 
                      at java.lang.reflect.Method.invoke(Native Method) 
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 

누군가 문제를 해결하도록 도와주십시오.

고마워요.

Answer 1

동일한 내용의 레이아웃에 동일한 단편을 두 번 추가했습니다. 이 문제를 방지하려면 add() 대신 replace()를 사용해야합니다.

Answer 2

FragmentPagerAapter를 사용하는 대신 FragmentStatePagerAdapter를 사용하고 어댑터의 notifydatasetchange() 메소드를 사용하여 뷰 페이지가 표시하는 조각의 수를 동적으로 변경하십시오. 코드는 아니지만 방향을 알려주지 않겠습니다.