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ToolTip with Popup Sound

Wednesday Aug 5th 1998 by Giancarlo Iovino

ToolTip with Popup Sound

  Download Source Code and Example


Introduction

Can we do something to make a tooltip attracts the user attention on it a little more? If the tooltip plays a sound when it pops up then maybe the things should get better. Well, this is a small class called CWavTipCtrl that inherits from CToolTipCtrl and adds exactly this feature.

Implementation details

The key points in the control implementation are:

  • How to play a wave file resource?
  • How to understand when the tooltip window pops up?

The first argument is covered by the article "Play Wav Resource" by Anthony Petruso.
The answer to the second question isn't so trivial as you can think. The first idea that comes in mind is to handle the WM_SHOWWINDOW message: wrong! To find the solution, I browsed in the MFC source code. Reading the code, it was clear that the tooltip "pops up" thanks to a call to SetWindowPos() that moves its window at the top of the Z-order (the depth order of all the visible windows). The message to be handled is therefore WM_WINDOWPOSCHANGED. But this message is sent also when the tooltip window is dismissed. For this reason, in the OnWindowPosChanged() function, it is necessary to check if the lpwndpos->flag field contains the SWP_SHOWWINDOW flag. Here is the code:

void CWavTipCtrl::OnWindowPosChanged(WINDOWPOS FAR* lpwndpos) 
{
	CToolTipCtrl::OnWindowPosChanged(lpwndpos);
	
	if (lpwndpos->flags & SWP_SHOWWINDOW)
		if (m_wWaveResourceID)
			PlayResource(m_wWaveResourceID);
}

How to use CWavTipCtrl

Using this class is very simple. Include the WavTipCtrl.cpp (and .h) in your project. Then add a tooltip to your window. For example, if you want to add CWavTipCtrl to a dialog, first add a tooltip component to it, then go in to the header file of the dialog class, #include "WavTipCtrl.h" and replace CToolTipCtrl with CWavTipCtrl. Include a custom wave resource in your project (e.g. IDR_TOOLTIP_SOUND). Now, just add a call to SetPopupSound(IDR_TOOLTIP_SOUND) in the OnInitDialog() body of your dialog. A last important thing: be aware that your program should be linked with the 'winmm.lib' static library, or a link error will occur.

Operations for CWawTipCtrl

void SetPopupSound(WORD wResourceID);
WORD GetPopupSound() const;

Note: If you don't want your CWavTipCtrl uses the popup sound, call SetPopupSound(NULL): NULL is considered as an invalid wave resource ID.

Author's note

I'm continuously working to improve this control. I'll be grateful to you if you mail me your comments, advice, or bug apparition reports!.

Updated: May, 21 1998

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