Android Tutorial

Android Tutorial 251

Using TabActivity

A screen layout with tabs consists of a TabActivity and a TabHost.

The TabHost consists of TabSpecs, a nested class of TabHost, which

contains the tab information including the tab title and the contents

of the tab. The contents of the tab can either be a predefined View,

an Activity launched through an Intent object, or the View can be

created with a factory provided by an implementation of

TabContentFactory.

Tabs aren’t as complex as they might sound at first. Each tab is

effectively a container for a View. That View can come from any

View that is ready to be shown, such as an XML layout file.

Alternatively, that View can come from launching an Activity. The

following example demonstrates each of these methods using View

objects and Activity objects created in the previous examples of

this chapter:

public class TabLayout extends TabActivity implements
android.control.TabHost.TabContentFactory {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
TabHost tabHost = getTabHost();
LayoutInflater.from(this).inflate(
R.layout.example_layout,tabHost.getTabContentView(), true);
tabHost.addTab(tabHost.newTabSpec(“tab1”).setIndicator
(“Grid”).setContent(new Intent(this, GridLayout.class)));
tabHost.addTab(tabHost.newTabSpec(“tab2”).setIndicator
(“List”).setContent(new Intent(this, List.class)));
tabHost.addTab(tabHost.newTabSpec(“tab3”).setIndicator
(“Basic”).setContent(R.id.two_texts));
tabHost.addTab(tabHost.newTabSpec(“tab4”).setIndicator
(“Factory”).setContent(this));
}
public View createTabContent(String tag) {
if (tag.compareTo(“tab4”) == 0) {