tab菜单的实现

 

 

下面的是res下drawable文件夹下的一个selector文件，作用主要是当每一个tab选项被点击，获得焦点以及被选中的时候背景都会发生变化 

<?xml version="1.0" encoding="UTF-8"?>
<selector
  xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_focused="false" android:state_selected="false" android:state_pressed="false" android:drawable="@drawable/tab_timeline_normal" /></span>
    <item android:state_focused="false" android:state_selected="true" android:state_pressed="false" android:drawable="@drawable/tab_timeline_active" /></span>
    <item android:state_focused="true" android:state_selected="false" android:state_pressed="false" android:drawable="@drawable/tab_timeline_normal" /></span>
    <item android:state_focused="true" android:state_selected="true" android:state_pressed="false" android:drawable="@drawable/tab_timeline_active" /></span>
    <item android:state_pressed="true" android:drawable="@drawable/tab_timeline_normal" /></span>
</selector>

注意一定要继承TabActivity  

public class MainActivity extends TabActivity {
    private TabHost tabHost;
    private RadioGroup mainbtGroup;
    private static final String HOME = "主页";
    private static final String REFER = "提及";
    private static final String SECRET = "私信";
    private static final String SEARCH = "搜索";
    private static final String ATTENTIION = "关注";


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.tabhost);//设置选项卡使用的布局文件

        tabHost = this.getTabHost();

        View view1 = View.inflate(MainActivity.this, R.layout.tab, null);
        ((ImageView) view1.findViewById(R.id.tab_imageview_icon)).setImageResource(R.drawable.tab_timeline_selector);//设置每一个tab的图标
        ((TextView) view1.findViewById(R.id.tab_textview_title)).setText(HOME);

        TabHost.TabSpec spec1 = tabHost.newTabSpec(HOME)
                .setIndicator(view1)
                .setContent(new Intent(this, HomeTimeLineActivity.class));
        tabHost.addTab(spec1);

        View view2 = View.inflate(MainActivity.this, R.layout.tab, null);
        ((ImageView) view2.findViewById(R.id.tab_imageview_icon)).setImageResource(R.drawable.tab_atme_selector);
        ((TextView) view2.findViewById(R.id.tab_textview_title)).setText(REFER);

        TabHost.TabSpec spec2 = tabHost.newTabSpec(REFER)
                .setIndicator(view2)
                .setContent(new Intent(this, ReferActivity.class));
        tabHost.addTab(spec2);

        View view3 = View.inflate(MainActivity.this, R.layout.tab, null);
        ((ImageView) view3.findViewById(R.id.tab_imageview_icon)).setImageResource(R.drawable.tab_message_selector);
        ((TextView) view3.findViewById(R.id.tab_textview_title)).setText(SECRET);

        TabHost.TabSpec spec3 = tabHost.newTabSpec(SECRET)
                .setIndicator(view3)
                .setContent(new Intent(this, MessageActivity.class));
        tabHost.addTab(spec3);

        View view4 = View.inflate(MainActivity.this, R.layout.tab, null);
        ((ImageView) view4.findViewById(R.id.tab_imageview_icon)).setImageResource(R.drawable.tab_explore_selector);
        ((TextView) view4.findViewById(R.id.tab_textview_title)).setText(SEARCH);

        TabHost.TabSpec spec4 = tabHost.newTabSpec(SEARCH)
                .setIndicator(view4)
                .setContent(new Intent(this, SearchActivity.class));
        tabHost.addTab(spec4);

        View view5 = View.inflate(MainActivity.this, R.layout.tab, null);
        ((ImageView) view5.findViewById(R.id.tab_imageview_icon)).setImageResource(R.drawable.tab_focus_selector);
        ((TextView) view5.findViewById(R.id.tab_textview_title)).setText(ATTENTIION);

        TabHost.TabSpec spec5 = tabHost.newTabSpec(ATTENTIION)
                .setIndicator(view5)
                .setContent(new Intent(this, AttentionActivity.class));
        tabHost.addTab(spec5);
    }

下面的就是tabhost布局文件 关键是tabhost，tabcontent和tabs这三个id一定要正确  

<?xml version="1.0" encoding="UTF-8"?>
<TabHost android:id="@android:id/tabhost"  android:layout_width="fill_parent" android:layout_height="fill_parent" xmlns:android="http://schemas.android.com/apk/res/android">
    <RelativeLayout android:orientation="vertical"
        android:layout_width="fill_parent" android:layout_height="fill_parent">
        <FrameLayout android:id="@android:id/tabcontent"
            android:layout_width="fill_parent" android:layout_height="fill_parent" />
        <TabWidget android:id="@android:id/tabs" <span style="background-color: #ff0000;">android:background="@drawable/tab_bkg"</span> android:fadingEdge="none"
            android:fadingEdgeLength="0.0px" android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true" />
    </RelativeLayout>
</TabHost>

android:layout_alignParentBottom="true" 把tab的五个按钮挨着父控件的底部，在android里面RelativeLayout很好用

下面的是每一个tab项的布局文件上面是图片下面是文字  

<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="wrap_content"
  xmlns:android="http://schemas.android.com/apk/res/android">
    <ImageView android:id="@+id/tab_imageview_icon" android:layout_width="fill_parent" android:layout_height="32.0dip" android:scaleType="fitCenter" />
    <TextView android:id="@+id/tab_textview_title" android:textSize="11.0sp"  android:ellipsize="marquee" android:gravity="center" android:layout_width="fill_parent" android:layout_height="wrap_content" android:singleLine="true" android:marqueeRepeatLimit="1" />
</LinearLayout>

 
是一张.9.png格式的图片，这个很有用哟在android里，经常用来处理图片拉升的问题。左边和上面的小点表示要拉伸的地方，右边和下面的表示内容区。关于.9.png格式图片在android里面得更多应用看 http://developer.android.com/guide/developing/tools/draw9patch.html