Removing a tab and the activity (intent) inside of it from a TabHost

Question

I have an app that can create tabs dynamically. And when I create a tab I initiate an activity as an intent. Like so:

private void addTab(Context packageContext, Class<?> newClass, TabHost mTabHost, String tabId, String tabLabel){
    // newClass is my Activity class that I want to start in the tab
    Intent intent = new Intent().setClass(packageContext, newClass);
    TabHost.TabSpec spec;
    spec = mTabHost.newTabSpec(tabId).setIndicator(tabLabel)
                  .setContent(intent);
    mTabHost.addTab(spec);
    mTabHost.setCurrentTabByTag(tabId);
}

Pretty standard. And it works great. Now, suppose that I have a button (or menuitem, whatever) in the activity that I instantiated inside of my tab. When the user presses this button, I want the activity, and the tab it is inside of, to be removed and destroyed.

I can't seem to find a simple way to do this. I have found the TabHost.clearAllTabs() function, but this destroys all tabs and activities, I just want to remove one.

Someone suggested I save a list of all Tabs that I have opened, and then call clearAllTabs(), after which I recreate all of my other tabs except for the one I don't want.

Something like this:

public static ArrayList<TabHost.TabSpec> list = new ArrayList<TabHost.TabSpec>();

I add this line to my addTab() function so that every tab I create is remember in my ArrayList:

list.add(spec);

And then when I want to remove my tab I run this function:

public static void removeTab(){
    list.remove(list.size()-1); // remove it from memory
    mTabHost.clearAllTabs();  // clear all tabs from the tabhost
    for(TabHost.TabSpec spec : list) // add all that you remember back
        mTabHost.addTab(spec);
}

This removes my tab from my ArrayList, removes all tabs, then recreates all the tabs remaining using my ArrayList. In theory it should work, but I get the following error when I try call this function:

FATAL EXCEPTION: main
java.lang.NullPointerException
at android.widget.TabWidget.setCurrentTab(TabWidget.java:342)
at android.widget.TabWidget.focusCurrentTab(TabWidget.java:366)
at android.widget.TabHost.setCurrentTab(TabHost.java:323)
at android.widget.TabHost.addTab(TabHost.java:216)
at com.example.myapp.TabManager.removeTab(QuikBrowser.java:86)
at com.example.myapp.TabManager.TabWindow.onOptionsItemSelected(TabWindow.java:91)
at android.app.Activity.onMenuItemSelected(Activity.java:2205)

For some reason, when adding a tab, it attempts to set the current tab, and it hits a null pointer exception.

If you guys could suggest another way of achieving what I want to do, or a way to fix my current method, I would appreciate it.

Answer 1

Try changing current tab to 0.

Something like:

getTabHost().setCurrentTab(0);
getTabHost().clearAllTabs();

I was reading that calling clearAllTabs(); will throw a nullpointerexception if you don't set the tabhost to the first tab (.setCurrentTab(0)) before calling (.clearAllTabs())

Also this answer may help? (How to remove tab from TabHost)