Android - FragmentTabHost gives me "No tab known for null tag"

Question

I have an activity that uses TabHost related to ViewPager . Although it works great, I decided to replace it with FragmentTabHost . However, after making some changes, I get a display exception whose messages are as follows.

 W/System.err(21723): java.lang.IllegalStateException: No tab known for tag null W/System.err (21723): at android.support.v4.app.FragmentTabHost.doTabChanged(FragmentTabHost.java:326) W/System.err(21723): at android.support.v4.app.FragmentTabHost.onAttachedToWindow(FragmentTabHost.java:276) W/System.err(21723): at android.view.View.dispatchAttachedToWindow(View.java:12064) W/System.err(21723): at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2707) W/System.err(21723): at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2714) W/System.err(21723): at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2714) W/System.err(21723): at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2714) W/System.err(21723): at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2714) W/System.err(21723): at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2714) W/System.err(21723): at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2714) W/System.err(21723): at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2714) W/System.err(21723): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1339) W/System.err(21723): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1131) W/System.err(21723): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4611) W/System.err(21723): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:725) W/System.err(21723): at android.view.Choreographer.doCallbacks(Choreographer.java:555) 

I basically made a class called IconSwipeyTabsView that extends FragmentTabHost and uses it in the main action or fragment. I did a lot of research on Google and StackOverflow, but none of them gave me a clear answer. FYI, these are the URLs of the two main files.

• swipey_tabs_stretched.xml
• IconSwipeyTabsView.java

If anyone can help me, I would really appreciate it. Thanks!

Answer 1

Are you calling IconSwipeyTabsView.setup(FragmentManager fm) in your activity?

A No tab known for tag null error can occur if the setup method in FragmentTabHost not called. If the search for this error leads to other reasons, be sure to create the FragmentTabHost object with one of the following:

FragmentTabHost.setup(Context context, FragmentManager manager)

FragmentTabHost.setup(Context context, FragmentManager manager, int containerId)

Details: FragmentTabHost