ShowWindow(SW_HIDE) problem

hi, im using visual c++ 6.0 with MFC and if i minimize my dialog window to the taskbar (not by code) and then use ShowWindow(SW_HIDE); on it, then i use ShowWindow(SW_RESTORE); to show it back again and then if i click the window from the taskbar to minimize it it just won't work anymore, i have to right click the window from the taskbar to fix it and make it minimize by clicking the window from the taskbar again..


note that there isn't any problem if i just minimize it first by code by using ShowWindow(SW_MINIMIZE);

does anybody know how to fix this? or is it a windows bug that cannot be fixed?

I'm assuming you have a mainwindow then create a modeless dialog.

I made a VS6 project. Created a dialog with min and max boxes, and parented to the desktop. Made menu items for showing the dialog, hiding the dialog, and restoring the dialog.

I run the application. Click the menu item to show the dialog (this creates it and shows it). Then I minimize the dialog with the min box. This puts the dialog in the taskbar. Both the application and dialog show in the taskbar. Then I click the hide menu item. This removes the dialog from the taskbar. Then I click the restore menu item. This shows the dialog back where it was before it was minimized. It is on top of the main window and it shows in the taskbar. I right click on the dialog in the taskbar and select minimize. It works for me.

If you did things differently you'll have to explain what you did.

Quote:

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Originally Posted by DaveH

I'm assuming you have a mainwindow then create a modeless dialog.

I made a VS6 project. Created a dialog with min and max boxes, and parented to the desktop. Made menu items for showing the dialog, hiding the dialog, and restoring the dialog.

I run the application. Click the menu item to show the dialog (this creates it and shows it). Then I minimize the dialog with the min box. This puts the dialog in the taskbar. Both the application and dialog show in the taskbar. Then I click the hide menu item. This removes the dialog from the taskbar. Then I click the restore menu item. This shows the dialog back where it was before it was minimized. It is on top of the main window and it shows in the taskbar. I right click on the dialog in the taskbar and select minimize. It works for me.

If you did things differently you'll have to explain what you did.

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ah sorry for not explaining things better, here is my code:

Code:

---

void CTESTDlg::OnClose()
{
    ShowWindow(SW_HIDE);
    ShowWindow(SW_RESTORE);
//  CDialog::OnClose();
}

---

anyway thanks to somebody who helped me i have found a solution and it seems to work:

Code:

---

void CTESTDlg::OnClose()
{
    ShowWindow(SW_HIDE);
    ShowWindow(SW_RESTORE);
    SendMessage(WM_NCLBUTTONDOWN, HTCAPTION, NULL);
//  CDialog::OnClose();
}

---

thing is im not 100% sure it is the right way, it seems that problem happens because i commented CDialog::OnClose(); which must be doing something important..

is there a way to see the CDialog::OnClose() source code to see what it is happening there?

thanks

Why are you hiding then restoring in onclose?

this is just a test project but my program hides the window on Close event and adds it to system tray where it is restored from there.. its like any program that goes to tray when you close it instead of just closing

But hiding and restoring in succession isn't doing anything. It just keeps the window where it is, no?

Quote:

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Originally Posted by DaveH

But hiding and restoring in succession isn't doing anything. It just keeps the window where it is, no?

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its just a test program and i placed restore there so it saves me a lot of trouble

i know it never closes unless you end task it but it reproduces the problem like on my main program

try and test it if you want..


edit:
its the same thing if i place the restore code in a button in a different window

actually the solution i posted doesn't work good all the time

on double click events it does weird things

if anybody knows a solution for this please post one..

thanks

I would suggest adding a delay between the hide and show. Sleep(1000); shoudl do the trick. That will give your message loop time to process the WM_ messages generted.

I'm still confused on how you are making your dialog. Is it the main window of the application or is it a secondary window?

CDialog::OnClose is going to destroy the window. I'm sure thats not what you want to do.


Edit : This link may help. http://www.codeproject.com/KB/shell/systemtray.aspx

Quote:

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Originally Posted by DaveH

I'm still confused on how you are making your dialog. Is it the main window of the application or is it a secondary window?

CDialog::OnClose is going to destroy the window. I'm sure thats not what you want to do.


Edit : This link may help. http://www.codeproject.com/KB/shell/systemtray.aspx

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it is the main window created modally, why is that so important?

the problem is that CDialog::OnClose() function does something which i don't know (i wish i knew), i deleted that line to prevent the window from closing and it probably expects the window to be closed which isn't, thats why clicking the window from the taskbar won't minimize it anymore..

edit: and by that i mean LEFT CLICKING the window from the taskbar not right clicking - select minimize menu that never has a problem and always works, its just that left clicking it won't minimize it anymore

edit2: sorry that link doesn't help because my problem is about using ShowWindow(SW_HIDE) line code in the WM_CLOSE event of the dialog and deleting the CDialog::OnClose() line from it (which seems to not be a good idea, because it does some important things i don't know about, thats why on a double click event on a system tray icon for example, showing the window and then left clicking the window from the taskbar won't minimize it anymore, it probably expects the window to be closed or something, it is closed by right clicking the window from the taskbar - Close)

The dialog creation was important because I couldn't reproduce your problem. I was trying to help, but couldn't without all the information.

The link could help because it is about sending a window to the system tray and re-opening the window from the tray icon. I looked at the code and it works. Again trying to help.

Quote:

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Originally Posted by DaveH

The dialog creation was important because I couldn't reproduce your problem. I was trying to help, but couldn't without all the information.

The link could help because it is about sending a window to the system tray and re-opening the window from the tray icon. I looked at the code and it works. Again trying to help.

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i wasn't trying to be mean, sorry if i made you think that :P

im just having a lot of problems and it never ends

by the way my application doesn't hide or go to tray when i click the minimize button, only when i click the close button

thanks

Quote:

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Originally Posted by eXistenZ

it is the main window created modally, why is that so important?

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Because MFC calls CDialog::EndDialog() on modal dialogs but calls an over-ride to CWnd::OnClose() for modeless ones?

Quote:

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Originally Posted by novacain

Because MFC calls CDialog::EndDialog() on modal dialogs but calls an over-ride to CWnd::OnClose() for modeless ones?

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oh sorry then, i didn't know about that

i still tested on both modeless and modal dialogs and it is the same problem and i handle only WM_CLOSE on them

thanks

i made a simple test project if you didn't get my problem and never reproduced it, it will say what to do exactly..

edit: please rename it to TEST.zip lol

I looked at your sample and I now see what you are talking about, but this doesn't send the window to the system tray, just to the task bar. In one of your replies you mentioned the system tray. Thats part of what confused me.

Quote:

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Originally Posted by DaveH

I looked at your sample and I now see what you are talking about, but this doesn't send the window to the system tray, just to the task bar. In one of your replies you mentioned the system tray. Thats part of what confused me.

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oh, this one doesn't but double clicking the second window is like double clicking the tray icon which should be pretty much the same, atleast it reproduces the problem exactly the same.. :P

sorry for not explaining things

i have found a way to make it work good using the SendMessage(WM_NCLBUTTONDOWN, HTCAPTION, 0); line of code in double click events..

Code:

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void CTEST2Dlg::OnLButtonDblClk(UINT nFlags, CPoint point)
{
        ((CTESTDlg*)m_parent)->ShowWindow(SW_RESTORE);
        ((CTESTDlg*)m_parent)->SetCapture(); //solution <-
        ((CTESTDlg*)m_parent)->SendMessage(WM_NCLBUTTONDOWN, HTCAPTION, 0);
        ReleaseCapture(); //solution <-
        DestroyWindow();
        CDialog::OnLButtonDblClk(nFlags, point);
}

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please get the test project again to test my solution if you want.. please rename it to TEST.zip..

can there be any "side effects" by using my code?

also can there be a better way to do this? this problem seems to happen ONLY when you click the Close menu from the taskbar from the window when it is minimized, i just don't understand why.. i even handled WM_SYSCOMMAND looking for SC_CLOSE hiding the dialog from there.. and it still didn't solve anything..

you can also remove the 2 lines of code commented with "//solution <-" to see what happens without them..

thanks