C win32 tab control

Question

Alright so first im coding in C using the win32 api, no mfc, no .net, no wxwidgets. I've created a window with the WC_TABCONTROL class, and have added tabs to it, everything works fine except... I need to have content in each tab, I got the impression from msdn that I needed to create a dialog for each page, and then load the dialog when the user selects a tab. Only problem with this is my main window isnt a dialog, so making the dialog box for the tab fit perfectly is not working too good.

So I'm wondering if there's a better way to do this? I thought about just hiding and showing different controls per tab but that doesn't seem like a good idea.

What I'd like is when my application starts it will resize the window and the tab control to the minimal size needed to fit all the tabs (3-4 tabs), and the window isn't going to be resizable which I guess simplifies things a little bit. I did this by following the example on msdn (Loading each dialog box into memory, looping thru each one and setting a RECT to the minimal size needed then resizing everything), problem is that the size is in dialog box units and I can't convert it to pixels because I don't have a HWND to the dialog box yet.

Basically my question is what is the best way to manage controls on a window with a tab control. So if I have a tab control and the user changes from tab1 to tab2, I want different controls to be displayed to the user.

Answer 1

The basic idea that MSDN is getting at is to have the controls for each tab within their own HWND. The benefit of this is that you can hide/show all the controls within a HWND by hiding/showing that parent HWND. This means that going from one tab to another is just a case of hiding one container HWND, and showing another, which is simpler and more elegant than having to hide/show groups of controls. (It also keeps the dialog handler code for each pane separate, which is usually what you want.) Both approaches are allowed, though: it's often more convenient to create a dialog, but you are not required to.

These container HWNDs don't have to be dialogs, but using a dialog means that windows will populate the contents from a .rc file for you and handle keyboard tabbing automatically. If you create your own HWND, you'll have to do this yourself. You could take a hybrid approach: start off with a dialog, but add your own controls in the WM_INITDIALOG handler if you need to, and even handle WM_SIZE to do custom layout so that the controls fit better.

If you go the create-your-own-HWND route, look up IsDialogMessage() for a simple way to add keyboard tabbing support to your own HWND; and also check out the WS_EX_CONTROLPARENT style so that tabbing between the tabs themselves and the controls in the container HWND work.

Re: "problem is that the size is in dialog box units and i cant convert it to pixels because i dont have a HWND to the dialog box yet." - you may be able to use CreateDialog to create the dialog as invisible - omit WS_VISIBLE from the .rc file - then you can measure/resize as appropriate before you show it.