레이아웃 잡는 설정법좀 봐주세요

+-----------------------------------------------+
+                                                              +
+             웹뷰                                          +
+                                                               +
+ +-------------------------------------------+ +
+ + 버튼1, 버튼2            버튼3(우측)++
+ +-------------------------------------------+ +

이런식으로 만들고 싶은데요.

가로보기를 하면 "버튼3" 이 우측으로 안가더라구요.

하단 설정좀 한번 부주세요


<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <WebView
     android:id="@+id/webview"
     android:layout_width="match_parent"   
     android:layout_height="0dp"
     android:layout_weight="1"
 />
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:background="#a0afc2">
       
 <Button android:id="@+id/prv_button"
            android:layout_width="wrap_content"
            android:layout_height="40dip"
            android:ellipsize="marquee"
            android:layout_marginLeft="5dip"
            android:drawableTop="@drawable/icon_prev"
            android:layout_marginTop="5dip"
   android:paddingTop="10dip"/>

 <Button android:id="@+id/next_button"
            android:layout_width="wrap_content"
            android:layout_height="40dip"
            android:ellipsize="marquee"
            android:drawableTop="@drawable/icon_next"
            android:layout_marginTop="5dip"
   android:paddingTop="10dip"/>        
              
 <Button android:id="@+id/home_button"
            android:layout_width="wrap_content"
            android:layout_height="40dip"
            android:ellipsize="marquee"
   android:layout_gravity="right"
            android:drawableTop="@drawable/icon_home"
            android:layout_marginTop="5dip"
   android:paddingTop="10dip"/>  
 
 </LinearLayout>
</LinearLayout>