android：片段中的tabhost，带有片段作为选项卡

Question

我试图拥有一个包含在片段中的标签主机，其中标签内容由片段定义。那好吧，

我从 google 的 FragmentsTab 示例开始。这显示了如何使用片段作为选项卡内容，但 TabHost 本身仍托管在活动中。同样，我需要将选项卡主机托管在片段中。

我以FragmentsTab 为例，将onCreate() 中的代码移动到我的Fragment 中的onCreateView()，

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View fragmentView = inflater.inflate(R.layout.detail_fragment, container);

    mTabHost = (TabHost) fragmentView.findViewById(android.R.id.tabhost);
    mTabHost.setup();

    mTabManager = new TabManager(getActivity(), mTabHost, R.id.realtabcontent);

    // TODO: localize
    mTabManager.addTab(mTabHost.newTabSpec("info").setIndicator("File Info"), InfoFragment.class, null);

    return fragmentView;
}

当我运行时，我得到了这个异常，

05-25 14:42:27.272: E/AndroidRuntime(4701): Caused by: java.lang.IllegalStateException: Recursive entry to executePendingTransactions
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1343)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:429)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at com.zimbra.octopus.android.TabManager.onTabChanged(TabManager.java:116)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.widget.TabHost.invokeOnTabChangeListener(TabHost.java:359)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.widget.TabHost.setCurrentTab(TabHost.java:344)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.widget.TabHost.addTab(TabHost.java:216)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at com.zimbra.octopus.android.TabManager.addTab(TabManager.java:92)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at com.zimbra.octopus.android.DetailFragment.onCreateView(DetailFragment.java:46)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:819)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1053)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:622)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1371)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:429)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at com.zimbra.octopus.android.TabManager.onTabChanged(TabManager.java:116)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.widget.TabHost.invokeOnTabChangeListener(TabHost.java:359)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.widget.TabHost.setCurrentTab(TabHost.java:344)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.widget.TabHost.addTab(TabHost.java:216)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at com.zimbra.octopus.android.TabManager.addTab(TabManager.java:92)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at com.zimbra.octopus.android.DetailFragment.onCreateView(DetailFragment.java:46)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:819)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1032)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentManagerImpl.addFragment(FragmentManager.java:1111)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:264)
05-25 14:42:27.272: E/AndroidRuntime(4701):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:563)

查看跟踪，我看到onCreateView() 递归调用DetailFragment（承载TabHost 的片段）。不知何故，对TabManager.addTab() 的调用（再次参见 FragmentsTab 示例）导致对DetailFragment.onCreateView() 的递归调用。

我做错了什么？这甚至可能吗？

Answer 1

Android 不允许您将一个片段嵌入到其他片段中。您的 logcat 表明您正在另一个片段事务中执行一个片段事务（即递归条目到 executePendingTransactions）。只是不允许，对不起！

Answer 2

在设置 TabHost 之前添加：

LocalActivityManager mLocalActivityManager = new LocalActivityManager(getActivity(), false);
mLocalActivityManager.dispatchCreate(savedInstanceState);
mTabHost.setup(mLocalActivityManager);