Resizing problems when applying a layout

Hi,

I have a Line Edit, a Horizontal Spacer, and a Push Button that I want to put into a layout. I have sized each widget to the geometry that I require, but when I put them into a layout, the layout changes the dimentions of the widgets! I've tried to Layout Horizontally, Layout in a Grid, and Layout Horizontally in a Splitter, and I can not get the sizes and placement that I want! Please tell me what I'm doing wrong.

Thank you.

First add the widgets, then the layout and finally tweak the sizePolicy, horizontalStretch, verticalStretch, minimumSize and maximumSize properties of those widgets.