Switching between different layouts

How do you specify min/max? This is what I have…

<template background-color="~ GreyCColor" background-color-draw-style="filled and stroked" class="CViewContainer" mouse-enabled="true" name="sample_edit_view" opacity="1" origin="0, 0" size="600, 500" transparent="false" wants-focus="false">

Thanks
Yan