Wait for me to hide

Posted on 1998-07-19
Last Modified: 2013-11-20
I want to hide my application window then capture the screen. I tried the code below but the screen shot capture parts of my application window. How to make my application wait till its window is completely hidden?

 Here is the code that does not work:

IsHide = AfxGetMainWnd()->SetWindowPos(AfxGetMainWnd(),0,0,0,0,SWP_HIDEWINDOW);
      AfxGetMainWnd()->UpdateWindow();   //Make sure it is hidden
            // Wait until everybody repaints themselves
        while (PeekMessage(&msg,NULL,0,0,PM_REMOVE) != 0)

      keybd_event(VK_SNAPSHOT,1,0,0); //full screen

Question by:khaledo
  • 2

Accepted Solution

atari earned 100 total points
ID: 1319453
I had a similar problem, I wanted to save the content of a mdi-window as .bmp after showing a CFileDialog for selecting a filename for my .bmp-file. After selecting a filename and clicking on OK the CFileDialog-Box is still displayed on the screen, so I cannot grab the content of my window. I solved this a little bit complicated with two timers, because the WM_TIMER-message  doesn't block any other messages, so all other messages are still processed. The problem for not updating the window-content is, that only after the end of your member-function the updating of your windows start, so the VK_UPDATE-message is much to early and will together processed while updating your windows.

So I solved it a little bit complicated, but it does work:
Start your screen-snapshot by calling AfxGetMainWnd()->OnBeginSnapshot();

Here are the protected declared functions in CMainFrame (my name for AfxGetMainWnd() in the following):

void CMainFrame::OnBeginSnapshot()
  snapshot=TRUE;  // declared as protected in MainFrame.h
  endsnapshot=FALSE; // similar

void CMainFrame::OnSnapshot()
  keybd_event(VK_SNAPSHOT,1,0,0); //full screen

void CMainFrame::OnEndSnapshot()

void CMainFrame::OnTimer(UINT nIDEvent)
  if (snapshot)
    if (endsnapshot)


The OnTimer()-call you can create with classwizard clicking on WM_TIMER-function for CMainFrame.

Maybe you can change the timer duration to get your best solution.

I hope this helps,

Author Comment

ID: 1319454

It worked, even when I set the timer to zero (because I thought it will be just like Wait() function if timer is not zero). I still do not understand why it worked. If updating starts after the end of the member function then we could simply put the function ShowWindow(SW_HIDE) in a separate member function and call it before the screen capturing. But such solution did not work while yours worked fine. If you can explain more I will be gratefull but for now, you solved my problem and I will accept your answer.

Expert Comment

ID: 1319455
I worked this problem out for several hours, tried everything like WaitForSingleObject() or SendMessage(WM_PAINT,0,0) for instantaneously redrawing the mainframe-window, but nothing seems to work. Somewhere I had read that the WM_TIMER-message doesn't block any other windows-message and if you read in help-file of VC++ you find 'The WM_TIMER message is a low-priority message.', what means that all higher priority messages like windows-redrawing and something else are first processed and the WM_TIMER is the last one that will be processed. Sorry, the statement, that refreshes begin after ending of member-function was my own mistake. I hope that you got a little more ideas about that !


Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
function returning CString in a regular win32 DLL 8 163
Folder Comparison 12 53
List out all word 7 261
WinWaitActive parameters 12 31
If you use Adobe Reader X it is possible you can't open OLE PDF documents in the standard. The reason is the 'save box mode' in adobe reader X. Many people think the protected Mode of adobe reader x is only to stop the write access. But this fe…
Exception Handling is in the core of any application that is able to dignify its name. In this article, I'll guide you through the process of writing a DRY (Don't Repeat Yourself) Exception Handling mechanism, using Aspect Oriented Programming.
This video will show you how to get GIT to work in Eclipse.   It will walk you through how to install the EGit plugin in eclipse and how to checkout an existing repository.
Learn how to create flexible layouts using relative units in CSS.  New relative units added in CSS3 include vw(viewports width), vh(viewports height), vmin(minimum of viewports height and width), and vmax (maximum of viewports height and width).

867 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

18 Experts available now in Live!

Get 1:1 Help Now