C / C++ / MFC

24-Aug-09 13:41

Hi guys,
I am relatively new to programming dx.

I just want to know if it is possible to draw a small blue semi transparent object on the desktop so that it will not affect the desktop. I mean you could still click your icons etc.
thanks !

Code-o-mat24-Aug-09 21:51

Code-o-mat

24-Aug-09 21:51

You could do that with an always-on-top Layered Window[^] (this would take care of the semi-transparency) with the WS_EX_TRANSPARENT[^] extended style set. How you can fit that in with DirectX is another question...

p.s: This[^] might be usefull too.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

nirishere25-Aug-09 0:00

25-Aug-09 0:00

Thanks !
And would you know how I can paint that window blue ?

Code-o-mat25-Aug-09 0:13

Code-o-mat

25-Aug-09 0:13

Well, that depends which path you took, if you checked out this[^] link and read the Using Layered Windows section you can either simply paint it blue in OnPaint or create a bitmap, paint it blue and use UpdateLayeredWindow. It mostly depends on your needs. Since you want a blue triangle, as i understood, you could use the WM_PAINT aproach with SetLayeredWindowAttributes[^] and next to the alpha value specify a colorkey, then fill your dialog in WM_PAINT with the "hollow color" and then paint a blue triangle onto this.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

nirishere25-Aug-09 0:45

25-Aug-09 0:45

Quote: "Hit testing of a layered window is based on the shape and transparency of the window. This means that the areas of the window that are color-keyed or whose alpha value is zero will let the mouse messages through."

I think layered windows is JUST what I need, thank you so much.

It might sound odd, but since I am really new to all this, would you know of a place where I can find a project for Layered windows so I can explore it a bit more ?

Code-o-mat25-Aug-09 0:56

Code-o-mat

25-Aug-09 0:56

Well, not really, sorry, but Google[^] is your friend and your search is as good as mine, and also you can look around here at Codeproject, there should be such articles or examples like this one[^] for example. Good luck.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

nirishere25-Aug-09 1:54

How to get the cursor position?

25-Aug-09 1:54

ok, thanks a bunch Code-o-mat ! Smile | :)

Orchus24-Aug-09 8:01

24-Aug-09 8:01

Hi,

In a nutshell: I need to display the location of the cursor when I click somewhere in the Windows Calculator window (or any other app beside my own).

I need to get the cursor position on the click event (WM_LBUTTONDOWN) when the click occurs in another window. In my test I am using calculator. I display with GetMessagePos or GetCursorPos the coordinates in 2 textboxes under the mouse move but whenever it goes beyond my app window, of course, my app message loop stop receiving those mouse move events.

This is in a barebone win32 no MFC app.

Thanks!!!

Antoine

Rajesh R Subramanian24-Aug-09 8:10

Rajesh R Subramanian

24-Aug-09 8:10

Orchus wrote:
In a nutshell: I need to display the location of the cursor when I click somewhere in the Windows Calculator window (or any other app beside my own).

You will need a global mouse hook to trap mouse events that occur outside of your application window. The following tutorial describes about hooks and DLLs in general, and has a sample mouse hook as well: http://www.flounder.com/hooks.htm[^]

It is a crappy thing, but it's life -^ Carlo Pallini

David Crow24-Aug-09 10:24

David Crow

24-Aug-09 10:24

Are you looking for SetCapture()?

"Old age is like a bank account. You withdraw later in life what you have deposited along the way." - Unknown

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

Orchus25-Aug-09 3:03

25-Aug-09 3:03

Hi,

Thank you for answering.
In this case I may have done something wrong it did not work...

case WM_MOUSEMOVE:
            //Set the position of the mouse in two textboxes (hX and hY)
    SetCapture(hWndTarget);
    TCHAR temp[256],temp2[256];
            long x,y;
    x=LOWORD(GetMessagePos());
    y=HIWORD(GetMessagePos());
        wsprintf(temp,_T("%d"),x);
    SetWindowText(hX,temp);
        wsprintf(temp2,_T("%d"),y);
    SetWindowText(hY,temp2);

Should this work?
I am running Windows 7 b7600 and VS2010 beta 1.

Thank you,

David Crow25-Aug-09 3:06

David Crow

25-Aug-09 3:06

Call SetCapture() when your app first starts up.

Orchus25-Aug-09 6:29

25-Aug-09 6:29

Hi,

It did not work either, at the end of the InitInstance() function.
If you have a small sample and you have the time to share it I would really appreciate it.

Thanks,

P.S.: The documentation, http://msdn.microsoft.com/en-us/library/ms646262%28VS.85%29.aspx[^], says that it will not work in non client area. ???

David Crow25-Aug-09 6:40

David Crow

25-Aug-09 6:40

Orchus wrote:
It did not work either...

Which means what exactly? Does SetCapture() return NULL? Are you not receiving any WM_MOUSEMOVE messages? Does the window handle belong to the current thread? Is it a foreground or background window?

Orchus25-Aug-09 10:03