Build UI from user controls

- [Instructor] As you start building your user interface…in your application, it'll get larger over time.…One thing you don't want to do is put all your UI…in a single file this modelithic main window.…You want to split it into parts.…There's a couple of approaches we could take.…One, instead of having these tabs like I have here,…I could have a single UI, the main window.…Then, I could create three separate windows:…a detail window, a weekly calendar window,…and a tour stops window.…Then, I could have some sort of navigation codes…that when you open up the main window and click on a button…or menu item, I would move over to the other windows.…

That works, but it's a bit awkward.…It's also hard to pass state between windows.…In WPF, there's some alternate approaches.…One approach is to to use what's called a page.…The other approach is to use a user control.…They're similar basically because they allow you…to build a composite UI in a page.…Then, you can use a navigation scheme…and something called a frame to move between pages.…