How to occupy an layout 75% of the screen and another 25% in Android Layout

How to occupy an layout 75% of the screen and another  25% -----



Steps

Use Linear Layouts-------------

  Current scenerio 

  1:  A main Linear layout contains two child linear layouts.

  2:  We have a Main Linear layout(Orientation ="horizontal")  and two child as "linTop" and "linBottom".


What we want??

  Occupy 75% of the screen using "linTop"

  occupy  25% of the screen using "linBottom".





For that use the following


Step1: In our Main linear layout,use attribute "Weight_sum =3"

step2: in our "linTop" layout ,use "Weight=2" ,width =0dip,Height=match_parent.

step3: In our "linBottom" layout,use weight =1,width =0dip,height=match_parent.



sample xml




<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/relMain"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="fill_parent"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:orientation="vertical"
        android:weightSum="5" >

        <LinearLayout
            android:id="@+id/linTop"
            android:layout_width="fill_parent"
            android:layout_height="0dip"
            android:layout_weight="3"
            android:orientation="vertical" >

            <SurfaceView
                android:id="@+id/surCamera"
                android:layout_width="fill_parent"
                android:layout_height="match_parent"
                android:layout_gravity="center"
                android:layout_marginBottom="20dip"
                android:layout_marginLeft="20dip"
                android:layout_marginRight="20dip"
                android:layout_marginTop="20dip" />
        </LinearLayout>

        <LinearLayout
            android:id="@+id/linBottom"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dip"
            android:layout_weight="2"
            android:orientation="vertical" >

            <Button
                android:id="@+id/btnCapture"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="Capture" />
        </LinearLayout>
    </LinearLayout>

</RelativeLayout>