ActionBar Tabs with Fragments

Fragments and Tabs

There are several ways to setup tabs with fragments. The easiest is using ActionBar tabs. Note: Standard ActionBar tabs are not supported in Gingerbread, so many people use ActionBarSherlock when Gingerbread must be supported. Google has also released a support ActionBarActivity class which can be used for compatible tabs. Thankfully, both the support approaches are more or less identical in code with a few class name tweaks.

Without Gingerbread Support

To setup tabs using ActionBar and fragments, you need to add a TabListener implementation to your application which defines the behavior of a tab when activated. A good default implementation is just adding this to FragmentTabListener.java.

Once you have created the FragmentTabListener from this snippet within your app, simply setup the ActionBar and define which tabs you would like to display and attach listeners for each tab:

public class MainActivity extends FragmentActivity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		setupTabs();
	}

	private void setupTabs() {
		ActionBar actionBar = getActionBar();
		actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
		actionBar.setDisplayShowTitleEnabled(true);

		Tab tab1 = actionBar
			.newTab()
			.setText("First")
			.setIcon(R.drawable.ic_home)
			.setTag("HomeTimelineFragment")
			.setTabListener(
				new FragmentTabListener<FirstFragment>(R.id.flContainer, this, "first",
								FirstFragment.class));

		actionBar.addTab(tab1);
		actionBar.selectTab(tab1);

		Tab tab2 = actionBar
			.newTab()
			.setText("Second")
			.setIcon(R.drawable.ic_mentions)
			.setTag("MentionsTimelineFragment")
			.setTabListener(
			    new FragmentTabListener<SecondFragment>(R.id.flContainer, this, "second",
								SecondFragment.class));

		actionBar.addTab(tab2);
	}
}

With ActionBarActivity Support

Google has released an updated support library "android-support-v7-appcompat" which includes official support for the ActionBar with Gingerbread compatibility. To use this, first, we need to upgrade to latest support library by opening the Android SDK Manager and verifying we have the latest "Android Support Library".

Now, we need to import the support library as a library project following the usual steps. File => Import => Existing Android Code... and then go to your sdk folder and select sdk => extras => android => support => v7 => appcompat.

Now, for your app, right-click and select "Properties..." and then add "android-support-v7-appcompat" as a library.

To setup tabs using ActionBar and fragments, you need to add a TabListener implementation to your application which defines the behavior of a tab when activated. A good default implementation is just adding this to SupportFragmentTabListener.java.

Once you have created the SupportFragmentTabListener from this snippet within your app, simply setup the ActionBar and define which tabs you would like to display and attach listeners for each tab:

public class MainActivity extends ActionBarActivity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		setupTabs();
	}

	private void setupTabs() {
		ActionBar actionBar = getSupportActionBar();
		actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
		actionBar.setDisplayShowTitleEnabled(true);

		Tab tab1 = actionBar
		    .newTab()
		    .setText("First")
		    .setIcon(R.drawable.ic_home)
		    .setTag("HomeTimelineFragment")
		    .setTabListener(new SupportFragmentTabListener<FirstFragment>(R.id.flContainer, this,
                        "first", FirstFragment.class));

		actionBar.addTab(tab1);
		actionBar.selectTab(tab1);

		Tab tab2 = actionBar
		    .newTab()
		    .setText("Second")
		    .setIcon(R.drawable.ic_mentions)
		    .setTag("MentionsTimelineFragment")
		    .setTabListener(new SupportFragmentTabListener<SecondFragment>(R.id.flContainer, this,
                        "second", SecondFragment.class));
		actionBar.addTab(tab2);
	}

}

With ActionBarSherlock

Using ActionBarSherlock, the code looks almost exactly the same. First you must download ActionBarSherlock.zip. Import the code into Eclipse and mark the project as a library. Next, add the library to your application. Watch the video on the FAQ page for a detailed guide.

With ActionBarSherlock installed and added to your app, add the gist code as the SherlockTabListener within your application.

Once you have created the SherlockTabListener from this snippet within your app, simply setup the ActionBar and define which tabs you would like to display and attaches listeners for each tab:

public class ActionBarSherlockActivity extends SherlockFragmentActivity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_action_bar_sherlock);
		setupTabs();
	}

	private void setupTabs() {
		ActionBar actionBar = getSupportActionBar();
		actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
		actionBar.setDisplayShowHomeEnabled(true);
		actionBar.setDisplayShowTitleEnabled(true);

		Tab tabFirst = actionBar
			.newTab()
			.setText("First")
			.setIcon(R.drawable.ic_launcher)
			.setTabListener(
				new SherlockTabListener<FirstFragment>(R.id.flContainer, this, "First",
								FirstFragment.class));

		actionBar.addTab(tabFirst);
		actionBar.selectTab(tabFirst);

		Tab tabSecond = actionBar
			.newTab()
			.setText("Second")
			.setIcon(R.drawable.ic_launcher)
			.setTabListener(
				new SherlockTabListener<SecondFragment>(R.id.flContainer, this, "Second",
							SecondFragment.class));

		actionBar.addTab(tabSecond);
	}
}

With this approach you can have easy tab navigation switching quickly between fragments.

Reference a Fragment in the Activity

If you need to reference a fragment instance from within the activity, you can refer to the fragment by it's "tag". For example, if you created the following tab:

Tab tab1 = actionBar
  ...
  .setTabListener(new SupportFragmentTabListener<FirstFragment>(R.id.flContainer, this,
      "first", FirstFragment.class));

You have assigned the tag "First" to that fragment and you can access the fragment for this tab later using findFragmentByTag:

FirstFragment fragmentFirst = getSupportFragmentManager().findFragmentByTag("first");

This will return the fragment instance embedded for that tab.