CODEWITHSUNDEEP
windowswinapi
KnowNothing
KnowNothing

Reputation: 119

my app cannot receive wm_timer msg

After created the window, i started a timer to do sth. the code like this:

SetTimer(hWnd, 1, 40, NULL);  //tick each 40 ms.

I traced the last error, which was 0. but i cannot receive wm_timer! code like this:

case WM_TIMER:
{
     //...
}

My IDE is VS2010, and OS is Windows7, so is there some speical case about my used environment?

P.S. okay i provide more code, it's a win32 app so in WinMain:

HWND hWnd = CreateWindow(...);  //style : WS_POPUP | WS_VISIBLE , return is good
SetTimer(hWnd, 1, 40, NULL);    //return is good too.
while (GetMessage(&msg, NULL, 0, 0))
{
    TranslateMessage(&msg);
    DispatchMessage(&msg);
}

and the WndProc:

switch(message)
{
case WM_TIMER:
{
    DebugBreak();  //no reaction
}
break;
.......
}

Upvotes: 2

Views: 1434

Answers (3)

Paul Daynes
Paul Daynes

Reputation: 1

I have the same problem. If I put "SetTimer()" in the WM_CREATE section it does not start. However, if I create a menu option that I need to click on, and the put the "SetTimer()" function in there, it works.

  case WM_CREATE:
    {
        SetTimer(hWnd, 1, 1000, NULL); // does not work here
        return 0:
    }
    case ID_TIMER_START:
    {
       SetTimer(hWnd, 1, 1000, NULL); // works here
       return 0;
    }

Upvotes: 0

JasonD
JasonD

Reputation: 16582

WM_TIMER won't fire if you're failing to consume other messages, as they will take priority. One cause of that, for example, is not correctly processing WM_PAINT messages (you must BeginPaint() / EndPaint() )

Upvotes: 2

mkey
mkey

Reputation: 535

To the best of my recollection, the problem stems from the fact you placed the SetTimer call too early. Place it in WM_CREATE.

switch(message)
{
    case WM_CREATE:
    {
        SetTimer(hWnd, 1, 40, NULL);
    }
    case WM_TIMER:
    {
        DebugBreak();  //no reaction
    }
    break;
    .......
}

I don't see any other reason why this should malfunction.

Upvotes: 1

Related Questions