Android腾讯微博客户端开发一:在下方的Tab的实现

红色的是res下drawable文件夹下的一个selector文件，内容是
Selector文件代码

<?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=<span style="background-color: #00ff00;">"@drawable/tab_timeline_normal" /></span>
<item android:state_focused="false" android:state_selected="true" android:state_pressed="false" android:drawable=<span style="background-color: #00ff00;">"@drawable/tab_timeline_active" /></span>
<item android:state_focused="true" android:state_selected="false" android:state_pressed="false" android:drawable=<span style="background-color: #00ff00;">"@drawable/tab_timeline_normal" /></span>
<item android:state_focused="true" android:state_selected="true" android:state_pressed="false" android:drawable=<span style="background-color: #00ff00;">"@drawable/tab_timeline_active" /></span>
<item android:state_pressed="true" android:drawable=<span style="background-color: #00ff00;">"@drawable/tab_timeline_normal" /></span>

</selector>

也是你按下时，和不按时等有一个效果上的改变，具体的可以参看关于selector的知识。绿色的就是两张不同效果的图片

[align=left]Mainactivity代码 [/align]

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);

tabHost = this.getTabHost();

View view1 = View.inflate(MainActivity.this, R.layout.tab, null);

((ImageView) view1.findViewById(R.id.tab_imageview_icon)).setImageResource(<span style="background-color: #ff0000;">R.drawable.tab_timeline_selector)</span>;

((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(<span style="background-color: #ff0000;">R.drawable.tab_atme_selector)</span>;
((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(<span style="background-color: #ff0000;">R.drawable.tab_message_selector)</span>;

((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(<span style="background-color: #ff0000;">R.drawable.tab_explore_selector</span>);

((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(<span style="background-color: #ff0000;">R.drawable.tab_focus_selector</span>);
((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);
}

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<a href="http://developer.android.com/guide/developing/tools/draw9patch.html">这里</a>

[align=left]Tabhost布局文件代码[/align]

<?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>

Tabhost布局文件代码

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

Tab布局文件，就是你看到的那5个按钮的布局文件代码

<?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>

[align=left] [/align]