Change Eclipse Layout Orientation

I want to know how to change the orientation of my layout. In manifest I have:

android:screenOrientation="landscape"

In layout.xml I have

andro开发者_开发百科id:orientation="horizontal"

but when I click the "layout" button it still appears as a vertical layout.

Thank You.

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There is a dropdown within the layout editor that allows you to select landscape or portrait orientation.