TabHosting can be used to explore and switch between different views or functional aspects of your app. In this tutorial we will make an activity and host three activities to its tab by using tab hosting . Tab layout is used for this purpose.

this code can be used to set the tabs.

        // Set TabChangeListener called when tab changed

                tabHost = getTabHost();
        tabHost.setOnTabChangedListener(this);

        TabHost.TabSpec spec;
        Intent intent;

        /************* TAB1 ************/
        // Create Intents to launch an Activity for the tab (to be reused)
        intent = new Intent().setClass(this, Tab1.class);
        spec = tabHost.newTabSpec("First").setIndicator("").setContent(intent);

        // Add intent to tab
        tabHost.addTab(spec);

        /************* TAB2 ************/
        intent = new Intent().setClass(this, Tab2.class);
        spec = tabHost.newTabSpec("Second").setIndicator("sd").setContent(intent);
        tabHost.addTab(spec);

        /************* TAB3 ************/
        intent = new Intent().setClass(this, Tab3.class);
        spec = tabHost.newTabSpec("Third").setIndicator("").setContent(intent);
        tabHost.addTab(spec);

        // Set drawable images to tab
        tabHost.getTabWidget().getChildAt(1)
                .setBackgroundResource(R.drawable.games);
        tabHost.getTabWidget().getChildAt(2)
                .setBackgroundResource(R.drawable.sports);

        // Set Tab1 as Default tab and change image
        tabHost.getTabWidget().setCurrentTab(0);
        tabHost.getTabWidget().getChildAt(0)
                .setBackgroundResource(R.drawable.foods);

Put the following code for the onTabChange Listner

@Override
    public void onTabChanged(String tabId) {

        /************ Called when tab changed *************/

        // ********* Check current selected tab and change according images
        // *******/

        for (int i = 0; i < tabHost.getTabWidget().getChildCount(); i++) {
            if (i == 0)
                tabHost.getTabWidget().getChildAt(i)
                        .setBackgroundResource(R.drawable.foods);
            else if (i == 1)
                tabHost.getTabWidget().getChildAt(i)
                        .setBackgroundResource(R.drawable.games);
            else if (i == 2)
                tabHost.getTabWidget().getChildAt(i)
                        .setBackgroundResource(R.drawable.sports);
        }

        Log.i("tabs", "CurrentTab: " + tabHost.getCurrentTab());

        if (tabHost.getCurrentTab() == 0)
            tabHost.getTabWidget().getChildAt(tabHost.getCurrentTab())
                    .setBackgroundResource(R.drawable.foods);
        else if (tabHost.getCurrentTab() == 1)
            tabHost.getTabWidget().getChildAt(tabHost.getCurrentTab())
                    .setBackgroundResource(R.drawable.games);
        else if (tabHost.getCurrentTab() == 2)
            tabHost.getTabWidget().getChildAt(tabHost.getCurrentTab())
                    .setBackgroundResource(R.drawable.sports);

    }

Put the three activities that has to be hosted .

Refrence from http://www.androidhive.info/2011/08/android-tab-layout-tutorial/,

http://developer.android.com/design/building-blocks/tabs.html