Question

我的活动中有以下代码：

     public void categoryClicked(int categoryId, String categoryName) {                 


ItemList newFragment = ItemList.newInstance(categoryId);
                    FragmentTransaction ft = getFragmentManager().beginTransaction();
                    ft.replace(R.id.itemContainer, newFragment);
                    ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
                    ft.addToBackStack(null);           
                    ft.commit();
            }

它按预期工作，我可以在点击几次到之前的状态后返回。但是，如果我只深入一个，我会得到以下异常：

03-10 22:17:19.895: ERROR/AndroidRuntime(23075): java.lang.IllegalStateException: Content view not yet created
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.ListFragment.ensureList(ListFragment.java:377)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.ListFragment.getListView(ListFragment.java:277)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at com.xxxxx.fragment.ItemList.onActivityCreated(ItemList.java:67)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:749)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:921)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.BackStackRecord.popFromBackStack(BackStackRecord.java:639)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.FragmentManagerImpl.popBackStackState(FragmentManager.java:1254)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.FragmentManagerImpl.popBackStackImmediate(FragmentManager.java:402)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.Activity.onBackPressed(Activity.java:2057)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.Activity.onKeyDown(Activity.java:1953)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.view.KeyEvent.dispatch(KeyEvent.java:2335)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.Activity.dispatchKeyEvent(Activity.java:2236)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1648)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.view.ViewRoot.deliverKeyEventPostIme(ViewRoot.java:2682)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.view.ViewRoot.handleFinishedEvent(ViewRoot.java:2655)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1952)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.os.Handler.dispatchMessage(Handler.java:99)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.os.Looper.loop(Looper.java:126)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at android.app.ActivityThread.main(ActivityThread.java:3997)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at java.lang.reflect.Method.invokeNative(Native Method)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at java.lang.reflect.Method.invoke(Method.java:491)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
03-10 22:17:19.895: ERROR/AndroidRuntime(23075):     at dalvik.system.NativeStart.main(Native Method)

所以基本上，如果我只调用一次替换，当我按下后退按钮时，它会出错。

另外，使用ListFragment，我是否必须将背景设置为白色？我没有触摸它，我可以看到旧的列表视图显示....

谢谢！

Answer 1

嗯，你遇到的问题是没有片段可以回复。这就是你能做的。 1：检查片段是否存在于后台堆栈中（通过给它命名），然后禁用返回 2：当您第一次启动编程时，将一个片段添加到backstack，就像它在单击之前的初始状态一样。即使在这种情况下，你仍然需要做一个chck，看看背板上是否还有东西可以回去。

Android Fragment backStack问题

1 个答案: