Qt Mobile App: Screen Size must be numerical?

[DooziiInc]

Greetings all,
Ive been evaluating using Qt for a new mobile app but have been a little perplexed at some of the design structures. I notice that page content can be aligned with regards to the parent, but there doesnt seem to be any way to have the page (the parent for the content) automatically adjust its size to the individual device (Android or iOS). Instead the QML file declares 640 x 480 as a default. When using Qt, do we have to compile a different value for each device we want to support? Is there no way to declare height and width as 100%?

Thanks

[DooziiInc]

I figured it out I think, by using Screen.width and Screen.height instead of a numerical value.