Android应用中怎么在底端显示选项卡

<&#63;xml version="1.0" encoding="utf-8" &#63;><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="vertical" android:layout_width="fill_parent"android:layout_height="fill_parent">  <TabHost android:id="@+id/edit_item_tab_host"  android:layout_width="fill_parent" android:layout_height="fill_parent">    <LinearLayout android:orientation="vertical"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:padding="5dp">      <FrameLayout android:id="@android:id/tabcontent"      android:layout_width="fill_parent"      android:layout_height="wrap_content"      android:padding="5dp" android:layout_weight="1">        <LinearLayout android:id="@+id/widget_layout_Blue"        android:layout_width="fill_parent"        android:layout_height="fill_parent"        android:orientation="vertical">          <RelativeLayout android:layout_width="fill_parent"          android:layout_height="wrap_content"          android:paddingLeft="3px"          android:paddingRight="3px">            <LinearLayout android:id="@+id/titleLayout_person_check_road_add"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:orientation="vertical">            </LinearLayout>            <LinearLayout            android:id="@+id/layout_person_check_road_add"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_toRightOf="@id/titleLayout_person_check_road_add"            android:layout_alignTop="@id/titleLayout_person_check_road_add"            android:orientation="vertical">            </LinearLayout>        </RelativeLayout>    </LinearLayout>    <LinearLayout android:id="@+id/widget_layout_red"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:orientation="vertical">      <RelativeLayout android:layout_width="fill_parent"      android:layout_height="wrap_content"      android:paddingLeft="3px" android:paddingRight="3px">        <LinearLayout android:id="@+id/titleLayout_person_check_road_add1"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:orientation="vertical">        </LinearLayout>        <LinearLayout        android:id="@+id/layout_person_check_road_add1"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_toRightOf="@id/titleLayout_person_check_road_add1"        android:layout_alignTop="@id/titleLayout_person_check_road_add1"        android:orientation="vertical">        </LinearLayout>    </RelativeLayout></LinearLayout><LinearLayout android:id="@+id/widget_layout_green"android:layout_width="fill_parent" android:layout_height="fill_parent"android:orientation="vertical">  <RelativeLayout android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:paddingLeft="3px" android:paddingRight="3px">    <LinearLayout android:id="@+id/titleLayout_person_check_road_add2"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:orientation="vertical"> </LinearLayout>    <LinearLayout android:id="@+id/layout_person_check_road_add2"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_toRightOf="@id/titleLayout_person_check_road_add2"    android:layout_alignTop="@id/titleLayout_person_check_road_add2"    android:orientation="vertical"> </LinearLayout>  </RelativeLayout></LinearLayout><LinearLayout android:id="@+id/widget_layout_yellow"android:layout_width="fill_parent" android:layout_height="fill_parent"android:orientation="vertical">  <RelativeLayout android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:paddingLeft="3px" android:paddingRight="3px">    <LinearLayout android:id="@+id/titleLayout_person_check_road_add3"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:orientation="vertical"> </LinearLayout>    <LinearLayout android:id="@+id/layout_person_check_road_add3"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_toRightOf="@id/titleLayout_person_check_road_add3"    android:layout_alignTop="@id/titleLayout_person_check_road_add3"    android:orientation="vertical"> </LinearLayout>  </RelativeLayout></LinearLayout></FrameLayout><TabWidget android:id="@android:id/tabs"android:layout_width="fill_parent" android:layout_height="wrap_content"android:layout_weight="0" /> </LinearLayout></TabHost></LinearLayout>