To use layout_marginLeft in a button style applied as a theme?

Question

Hi,

I used an attribute layout_marginLeft="30dip" in a style defined for buttons. When I apply this style individually for each button, the left margin is placed as I wanted. But then I defined another style inheritting from theme. In this style, I assigned my button style to the attribute android:buttonStyle and applied this as theme. However, the left margin property is ignored. Any idea what I must do here?

style.xml as follows :

<style name="btnstyle" parent="@android:style/Widget.Button">
    <item name="android:layout_height">wrap_content</item>
             <item name="android:layout_width">wrap_content</item>
             <item name="android:layout_marginLeft">30dip</item>
    <item name="android:textColor">#FFFFFF</item>       
</style> 

<style name="appstyle" parent="android:Theme"> 
    <item name="android:buttonStyle">@style/btnstyle</item> 
</style>