Android tabhost example

You can implement the tab effect in Android by referencing tabhost in the layout file, obtaining the tabhost instance by ID in the activity, or directly inheriting tabactivity, directly obtain the tabhost instance.

The main code of the program is as follows:
1. layout file tab. in the layout file, note that if the tabhost label references the tabwidget label, you must set its Android: Id = "@ Android: ID/tabs ", the framelayout tag ID must be set to Android: Id = "@ Android: ID/tabcontent". Otherwise, a null pointer exception occurs.

<? XML version = "1.0" encoding = "UTF-8"?>
<Tabhost xmlns: Android = "http://schemas.android.com/apk/res/android"
Android: Id = "@ + ID/tabhost"
Android: layout_width = "match_parent"
Android: layout_height = "match_parent">
<Relativelayout
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent">
<! -- Set the tab title attributes and set the title

Align the bottom -->
<Tabwidget
Android: Id = "@ Android: ID/tabs"
Android: layout_alignparentbottom = "true" // This

A statement is used to set tabwidget to the bottom of the screen, which is at the top of the screen by default.
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content">
</Tabwidget>
<! -- Set the tab body Attributes -->
<Framelayout
Android: Id = "@ Android: ID/tabcontent"
Android: layout_width = "match_parent"
Android: layout_height = "match_parent">
<Linearlayout
Android: Id = "@ + ID/tab1"
Android: Orientation = "vertical"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"
Android: paddingtop = "20dip">
<Imageview

Android: layout_width = "wrap_content"

Android: layout_height = "wrap_content"

Android: layout_gravity = "center"
Android: src = "@ drawable/home"/>
</Linearlayout>
<Linearlayout
Android: Id = "@ + ID/tab2"
Android: Orientation = "vertical"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"
Android: paddingtop = "20dip">
<Imageview

Android: layout_width = "wrap_content"

Android: layout_height = "wrap_content"

Android: layout_gravity = "center"

Android: src = "@ drawable/garbage"/>
</Linearlayout>
<Linearlayout
Android: Id = "@ + ID/tab3"
Android: Orientation = "vertical"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"
Android: paddingtop = "20dip">
<Imageview

Android: layout_width = "wrap_content"

Android: layout_height = "wrap_content"

Android: layout_gravity = "center"
Android: src = "@ drawable/help"/>
</Linearlayout>
</Framelayout>
</Relativelayout>
</Tabhost>

Activity file tabdemo. Java

Import Android. App. activity;
Import Android. OS. Bundle;
Import Android. View. gravity;
Import Android. widget. tabhost;
Import Android. widget. Toast;
Import Android. widget. tabhost. ontabchangelistener;

Import com. KF. samples5.r;

Public class tabdemo extends activity {

@ Override
Protected void oncreate (bundle savedinstancestate ){
// Todo auto-generated method stub
Super. oncreate (savedinstancestate );
Setcontentview (R. layout. Tab );
Tabhost host = (tabhost) findviewbyid (R. Id. tabhost );
Host. Setup ();

Tabhost. tabspec homespec = host. newtabspec ("home"); // This

Param will be used as Tabid.
Homespec. setindicator (null, // This param will diplay as title.
Getresources (). getdrawable (R. drawable. home_normal ));
Homespec. setcontent (R. Id. tab1 );
Host. addtab (homespec );

Tabhost. tabspec garbagespec = host. newtabspec ("garbage ");
Garbagespec. setindicator (null, getresources (). getdrawable

(R. drawable. garbage_normal ));
Garbagespec. setcontent (R. Id. tab2 );
Host. addtab (garbagespec );

Tabhost. tabspec maybespec = host. newtabspec ("help ");
Maybespec. setindicator (null, getresources (). getdrawable

(R. drawable. help_normal ));
Maybespec. setcontent (R. Id. tab3 );
Host. addtab (maybespec );

Host. setontabchangedlistener (New ontabchangelistener (){

@ Override
Public void ontabchanged (string Tabid ){
// Todo auto-generated method stub
Toast = toast. maketext (tabdemo. This, Tabid, Toast. length_short );
Toast. setgravity (gravity. center_horizontal, 0, 50 );
Toast. Show ();
}
});

// Host. setcurrenttabbytag ("home ");
Toast = toast. maketext (tabdemo. This, "home ",

Toast. length_short );
Toast. setgravity (gravity. center_horizontal, 0, 50 );
Toast. Show ();
}
}