很多个ImageView在RelativeLayout中放置一个横排，怎样使整体居中

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<LinearLayout xmlns:android="url/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"唯稿纳
android:layout_height="fill_parent">敬孙

<TextView
android:background="@drawable/red"
android:layout_width="0dip"
android:layout_height="fill_parent"
android:layout_weight="1"/>

<TextView
android:background="@drawable/green"
android:layout_width="0dip"
android:layout_height="fill_parent"
android:layout_weight="1"/指没>

<TextView
android:background="@drawable/blue"
android:layout_width="0dip"
android:layout_height="fill_parent"
android:layout_weight="1"/>

<TextView
android:background="@drawable/yellow"
android:layout_width="0dip"
android:layout_height="fill_parent"
android:layout_weight="1"/>

</LinearLayout>

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