I have this XP app (win32 C++) that I am just now testing under Windows7 (vista actually, but it does the same thing in windows 7).
I'm surprised that virtually the only issue I'm encountering is the following:
None of the scroll bars in a complex modelless dialog are functioning correctly. The main problem is the scroll thumb is not responding - just stays locked in position if you try and move it. Have had no issues going all the way back to win98, win2000, and winxp. Only in windows 7/Vista just now
But there is no commonality in the scrollbars in this dialog to explain it: One is in a plain richtext control created through a resource file. Another is in a richtext created through CreateWindow. And yet a third scrollbar is in a custom window class. None of them are working correctly (although you can make them scroll by right clicking and selected "Scroll Here".)
So I'm presuming maybe most encountered this a few years ago when porting to Window7/Vista for the first time, but I'm not finding anything in google now.
For modeless dialogs, you have to run IsDialogMessage in the main application GetMessage Loop, so messages for modeless dialogs are not subject to TranslateMessage and DispatchMessage. So I was doing that previously. However, Vista/Win7 doesn't like WM_MOUSEMOVE, and WM_LBUTTONDOWN and WM_LBUTTONUP to be bypassed like that for the dialog (i.e. they need to stay in the main App message loop). At least this was the problem in my case. I check for those message types now in the main message loop and that solved my problem. Can't explain it necessarily. Also couldn't explain why no one's encountered this previously (could be some idiosyncracy of my set up I guess). THanks for those who looked into this.
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I have a modeless dialog that is sometimes left up on the screen when I go to close my main app. If I close it manually, all destructors get called properly. But so far, if I try to do it through C++ code, I encounter problems in the Debug build that don't give me confidence in what is happening in the Release build.
What is the correct way to close a modelss dialog? Documentation for PostQuitMessage() indicates it closes entire threads (is a modeless dialog run in a separate thread, or just part of the single MFC App UI thread?). Calling DestroyWindow() gives me issues in practice. Sending a WM_CLOSE doesn't feel like the right thing to do. And CWnd::EndDialog() only applies to Modal dialogs. Does the correct answer lie among these... or somewhere else?
I'm trying to use SendMessage to post mouse clicks to a background window (Chrome), which works fine, but brings the window to front after every click. Is there any way to avoid that?
Before anyone says this is a duplicate question, please make sure that the other topic actually mentions not activating the target window, because I couldn't find any.
Update: aha, hiding the window does the trick, almost. It receives simulated mouse/keyboard events as intended, and doesn't show up on screen. However, I can just barely use my own mouse to navigate around the computer, and keyboard input is completely disrupted.
So my question is, how does sending messages to a window affect other applications? Since I'm not actually simulating mouse/keyboard events, shouldn't the other windows be completely oblivious to this?
Is it possibly related to the window calling SetCapture when it receives WM_LBUTTONDOWN? And how would I avoid that, other than hooking the API call (which would be very, very ugly for such a small task)?
The default handling provided by the system (via DefWindowProc) causes windows to come to the front (when clicked on) as a response to the WM_MOUSEACTIVATE message, not WM_LBUTTONDOWN.
The fact that Chrome comes to the front in response to WM_LBUTTONDOWN suggests that it's something Chrome is specifically doing, rather than default system behaviour that you might be able to prevent in some way.
The source code to Chrome is available; I suggest you have a look at it and see if it is indeed something Chrome is doing itself. If so, the only practical way you would be able to prevent it (short of compiling your own version of Chrome) is to inject code into Chrome's process and sub-class its main window procedure.
Using mixed managed/unmanaged C++ (Visual Studio 2008) I'm opening a windows form child window from a DirectX application. Weird stuff indeed, but it works, mostly. If I use showDialog() the child window works perfectly, but obviously the main app stops running (until the child is closed). If I use show() life is good, but the child has subtle issues. A textbox works and accepts input for example, but you can no longer use the Tab key to move to different controls. Mnemonics (Alt+hotkey) have stopped working as well.
I'm a huge keyboard shortcut fan, so this is very annoying. To make it worse, I'm not even sure how to Google this issue. Any help would be greatly appreciated.
To resolve the tabbing problem either use a separate thread to create the dialog and call showDialog(), or call IsDialogMessage in your main message loop.
How would one prevent the little dotted square that appears on a button when it has the keyboard focus in a dialog. (w/ apologies for the technical jargon). At one point I hacked together a solution by subclassing a button WindowProc and subverting some windows messages, but wanted to know the correct way.
There's actually a problem with another control in the dialog also involving the keyboard. This other control is actually also a button, but being used as a group box or panel, not as a functioning button. But when I hit the tab key in the dialog, this group box "button" comes to the foreground obscuring the static controls on top of it, so I wanted to prevent that.
For both of the above, I tried turning off WS_TABSTOP - didn't help.)
Both of my problems mentioned above were solved by subclassing the WndProcs and returning 0 in response to message 0x128 and discarding it. Even Spy++ could not identify this message 0x128, and I don't have it in any header. But its sent to every control in the dialog the first time tab is hit in the dialog.
(I did try BN_SETFOCUS as described above and also WM_SETFOCUS but it didn't help.)
So if anyone knows where to find what windows message 0x128 is...
The correct way is to write your own button control instead of using the default Windows one.
Alternatively, you can prevent if from ever getting keyboard focus.
Is there a way to create a modeless dialog box in C++ MFC which always stays on top of the other windows in the application? I'm thinking sort of like the Find dialog in Visual Studio 2005 - where it stays on top, but you can still edit the underlying text.
(If it makes any difference, it's not MDI; it's a dialog-based app)
Note: This does not work under Windows 10, and may not work under Windows 7 and 8 (Reports vary).
From Nish:
###Making your dialog stay on top
Haven't you seen programs which have
an "always-stay-on-top" option? Well
the unbelievable thing is that you can
make your dialog stay on top with just
one line of code. Simply put the
following line in your dialog class's
OnInitDialog() function.
SetWindowPos(&this->wndTopMost,0,0,0,0,SWP_NOMOVE|SWP_NOSIZE);
Basically what we are doing is to use
the SetWindowPos function to change
the Z-order of our dialog window. We
make our dialog stay on top of all
other windows by moving it to the top
of the Z-order. Now even when you
activate some other window, our window
will stay on top. But I'd advise you
to make sure you know exactly what you
are doing when you do this, for it
might annoy people if they can't get
your window out of the way when they
want to do that.
As you mentioned in the comments, the above line makes the window sit on top of every application. You'll need to do
SetWindowPos(&this->wndTop,0,0,0,0,SWP_NOMOVE|SWP_NOSIZE);
To make a window sit on top of only your application.
The accepted answer fails for Windows 7 or above. (Or perhaps its me)
But making the modeless dialog as popup instead of child solves it.
It now gets positioned wrt main dialog window but you can write code to constrain anywhere.
Using the no border or top bar makes it a simple window.
It worked for me in Microsoft Windows Version 10.0.18362.476. Had to put SetWindowPos(&this->wndTopMost,0,0,0,0,SWP_NOMOVE|SWP_NOSIZE); in OnInitDialog and make the dialog as a PopUp.