Losing Focus in a DirectX Project

[Electroman]

I bet most people in this forum have came across this one before, when say you press Alt + Tab and your DirectX App loses focus it doesn't like it, yeah? Well I know you can Restore Surfaces then reload the images but does anyone know if theres a way just to stop it from losing the surfaces in the first place?
Thanx,

Paul

[Madboy]

you mean like how DOS is made exclusively?

Not sure, but im sure theres some API for it, did you look at PSC?

[Electroman]

Originally posted by Madboy
you mean like how DOS is made exclusively?

Not sure, but im sure theres some API for it, did you look at PSC?

Well even if you set DirectX to Exclusive its still happens, I don't know if theres some kind of setting in Dx or something. PSC??

Originally posted by Madboy
Not sure, but im sure

.

[Madboy]

Originally posted by Electroman
PSC??

Planet-Source-Code

link in signature

[Electroman]

doh!

[NoteMe]

Yeah you can disable the Alt+Tab buttons, but it is not recomended at all. It is really anoying, and all real DX books are trying to make you understand how irritating it is. And an other thing is that some IMs and other stuff might pop up in the window on some machines too, and that will make you loos the focus too, so the best thing to do is to always check if you have the focus and if not, restore it...

[Electroman]

As soon as you lose focus tho you need to retsore all the surfaces right, and how exactly do you check for focus and get focus back?

[Son of Makuta]

You can check for focus by using GetActiveWindow, a minor API call:

Public Declare Function GetActiveWindow Lib "user32" () As Long

If GetActiveWindow = Form1.hWnd Then
    'You've got the focus
Else
    'You've not
End If

Dunno about restoring surfaces though...? My program throws automation errors when it restores, but this method might work for you though, 'cos I'm not using many surfaces, mostly textures and sprites and stuff. (And because I'm hideously error-prone at times.) I presume your Form_Load sub holds all the surface-loading code, yeah? You can cheat: whenever the form reactivates, bomb it out and load it again.

The best way to go about that is just to use a little sub called Form_Activate and a variable saying when the program's tabbed out.

Private Sub Form_Load
    'The lot
    TabOut = False
End Sub

Private Sub Form_Activate
    If TabOut = True Then
        Unload Me   'Not sure if this is necessary
        Form_Load
    End If
End Sub

'Later on, in the main loop...
Private Sub RenderAll         'Called by the main loop
    If GetActiveWindow = Me.hWnd Then
        'Do the funky rendering gibbon
    Else
        TabOut = True
    End If
End Sub

That any good for you?

Edit: You do know that [VBCode] thing [/VBCode] in your sig doesn't work, don't you?