Apps Layout: Landscape doesn't work properly?

[Jan123]

Hello,

if I want to support multiple screen sizes (in Eclipse) I work with the sizes small, normal, large and xlarge. That works fine in portrait-modus, but not in landscape Modus. For instance If I create a layout for a 3,2" device in landscape-modus, it doesn't fit for a 3,3" device in landscape Modus. Because it Looks not symetric in a 3,3" device then. It seems like I am doing s.th. wrong?

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <Button
        android:id="@+id/Button01"
        android:layout_width="150dp"
        android:layout_height="75dp"
        android:layout_alignLeft="@+id/button1"
        android:layout_alignParentBottom="true"
        android:layout_marginBottom="50dp"
        android:text="Button" />

    <Button
        android:id="@+id/Button02"
        android:layout_width="150dp"
        android:layout_height="75dp"
        android:layout_alignBaseline="@+id/button1"
        android:layout_alignBottom="@+id/button1"
        android:layout_marginLeft="25dp"
        android:layout_toRightOf="@+id/button1"
        android:text="Button" />

    <Button
        android:id="@+id/Button03"
        android:layout_width="150dp"
        android:layout_height="75dp"
        android:layout_alignBaseline="@+id/Button01"
        android:layout_alignBottom="@+id/Button01"
        android:layout_alignLeft="@+id/Button02"
        android:text="Button" />

    <Button
        android:id="@+id/button1"
        android:layout_width="150dp"
        android:layout_height="75dp"
        android:layout_above="@+id/Button01"
        android:layout_alignParentLeft="true"
        android:layout_marginBottom="46dp"
        android:layout_marginLeft="78dp"
        android:text="Button" />

</RelativeLayout>

Beste regards,
Jan123