MSDN - "ShellProc Function", "RegisterShellHookWindow Function":
HSHELL_WINDOWCREATED => A top-level, unowned window has been created.
HSHELL_WINDOWDESTROYED => A top-level, unowned window is about to be destroyed.
But:
we'll get HSHELL_WINDOWDESTROYED/HSHELL_WINDOWCREATED also when only do Hide/Show (or set/cancel WS_EX_TOOLWINDOW) to any top-level unowned window (with taskbar button).
Why? Taskbar button isn't "true" window, isn't it?
This question primarily for MS insiders here.
Related
When cursor honver over the title zone (HTCAPTION),press left mouse button, then you can drag a window and move it. When you release the left mouse button , you can stop this dragging action. When you move a window , it triggered the message WM_MOVE. When release the mouse button , I don't know which message should be handled for catching this action.
What I'm doing is when you drag a window(let's say window A) into another window's area(window B), make window A a child window of window B, when drag window A out of window B's area , make window A a WS_POPUP window, without WS_CHILD style.
I handled message WM_MOVE and WM_CAPTURECHANGED( I don't think it's the right one).
In WM_CAPTURECHANGED , I found something wired. The API SetWindowPos seemed not work well. To be percise, the 3rd and the 4th parmater , specified the window's position not work.
case WM_CAPTURECHANGED: {
RECT rcc;
GetClientRect(main,&rcc);
// here main is the handler of window B , hwnd is for window A,as referrence above.
if(docker_mode==DOCKER_LEFT) {
// docker_mode is assigned by WM_MOVE message handler. recording which area window A was moved into.
if((WS_CHILD&GetWindowLongPtr(hwnd,GWL_STYLE))!=WS_CHILD) {
SetWindowLongPtr(hwnd,GWL_STYLE,(~WS_POPUP)&(WS_CHILD|GetWindowLongPtr(hwnd,GWL_STYLE)));
SetParent(hwnd,main);
}
//The following code not work. It should be moved into the left-top corner of window B,
//but NOT in fact.
SetWindowPos(hwnd,NULL,0,0,300,rcc.bottom-rcc.top,SWP_NOZORDER);
}
else {
if((WS_CHILD&GetWindowLongPtr(hwnd,GWL_STYLE))==WS_CHILD) {
SetWindowLongPtr(hwnd,GWL_STYLE,((~WS_CHILD)&GetWindowLongPtr(hwnd,GWL_STYLE))|WS_POPUP);
SetParent(hwnd,NULL);
SetWindowPos(hwnd,NULL,300,0,0,0,SWP_NOMOVE|SWP_NOSIZE|SWP_NOZORDER|SWP_FRAMECHANGED);
}
}
} break;
SetWindowLongPtr(...,GWL_STYLE,...) was called to set the window style . A top level has no WS_CHILD style, and the handle of parent window should be NULL , I use SetParent(hwnd,NULL) to do this. A child window should have WS_CHILD style, and the parent window should be assigned.
I put a button into the window , and copy those code into the handle of button click event. When click the button it works well , change a popup window into a sub window , put the sub window into right position. SetWindowPos has no problem at all. I don't know why.
SetWindowPos is a very interesting API when working on WM_CAPTURECHANGED handler. What's wrong ?
If I recall correctly, when the user drags a window, that window receives a sequence of messages like this:
WM_ENTERSIZEMOVE
WM_WINDOWPOSCHANGING
WM_MOVING
WM_WINDOWPOSCHANGED
WM_MOVE
WM_EXITSIZEMOVE
(There are other messages, too, but I don't think you need to worry about those. There may be some final messages after WM_EXITSIZEMOVE with the final resting place for the window.)
The steps in the middle will happen repeatedly as the user drags the window. (In the Old Days, only some of those middle steps would happen, and there may still be an option to cut down on the messages during the drag operation.)
You can try using Spy++ (included with Visual Studio) to confirm the above.
So you shouldn't need to deal with the mouse capture messages. Have window A watch for WM_EXITSIZEMOVE. At that point, window A can check its position to see if it overlaps the target window (B). If it does overlap, then it should send a message to window B to initiate the docking operation.
My window should be on top of a specific "target" window that I don't have control over.
When the target window is activated, I call SetWindowPos with HWND_TOPMOST to place my window on top of it while the target can still be the active window.
When the target window is no longer the foreground window, I want my window to still be on top of the target window, but no longer topmost, so other windows are not covered by it.
Two ideas I had:
Call SetWindowPos with hWndInsertAfter to be the just activated window. This fails when the just activated window is topmost, because my window then does not lose the topmost status. Another issue with this: If the just activated window is the desktop, then my window is placed below the target window.
Call SetWindowPos with HWND_NOTOPMOST to lose the topmost status. However, this brings my window to the top of all non-topmost windows, so it covers the just activated window. To fix this I have to bring the just activated window on top again with another SetWindowPos with HWND_TOP. This feels like the wrong way to do it and may cause flicker.
Is it possible to have a window just stop being topmost and placing it below the current foreground window?
The only automatic method to make a window permanently on top of another one whether the target window is top-most or not is an owner/owned relationship. You could try using SetParent to create this relationship but note that Raymond Chen does say it's not recommended.
Assuming you're tracking window activations somehow, I think your SetWindowPos idea (the first one) is the way to do it, with the following modification:
When the target window is active, set your window to HWND_TOPMOST
When the target loses activation, insert your window after the target window's immediate predecessor in the z-order (i.e. effectively still on top of the target window, but not top-most)
Something like this psuedo-code:
if (foregroundwindow == targetwindow)
SetWindowPos(my_window, HWND_TOPMOST, ...);
else
{
HWND hwndPred = GetWindow(targetwindow, GW_HWNDPREV);
if (!hwndPred)
{
// no predecessor so my_window will still be on top, just not top-most any more
if (GetWindowLong(targetwindow, GWL_EXSTYLE) & WS_EX_TOPMOST)
hwndPred = HWND_NOTOPMOST;
}
SetWindowPos(my_window, hwndPred, ...);
}
I'm writing a small window manager, that add a basic decoration around a window, but actually i have several question about adding/remove decoration of a window.
First Question
Actually the decoration is added during MapNotify event, but it seems to be not a good idea, because it add decoration also to a menu opened by an application everytime the mapnotify is fired with a new window, but i want only to add decoration to main window. Maybe i have to check if the current window is a child of another window ? Actually my code just create the decoration window with a specific name, so at every MapNotify request i give the decoration window a dummy name (Parent) to distinguish it from all other windows in that way if the MapNotify event is launched on a decoration window, at least it doesn't add another decoration.
But i don't understand if MapNotify is launched not only for parent window but also for childrend probably the risk is that i add more than one decoration window.
The actual code is the following:
void map_notify_handler(XEvent local_event, Display* display, ScreenInfos infos){
printf("Map Notify\n");
XWindowAttributes win_attr;
char *child_name;
XGetWindowAttributes(display, local_event.xmap.window, &win_attr);
XFetchName(display, local_event.xmap.window, &child_name);
printf("Attributes: W: %d - H: %d - Name: %s\n", win_attr.width, win_attr.height, child_name);
if(child_name!=NULL){
if(strcmp(child_name, "Parent")){
Window new_win = draw_window_with_name(display, RootWindow(display, infos.screen_num), "Parent", infos.screen_num,
win_attr.x, win_attr.y, win_attr.width, win_attr.height+DECORATION_HEIGHT, 0,
BlackPixel(display, infos.screen_num));
XMapWindow(display, new_win);
XReparentWindow(display,local_event.xmap.window, new_win,0, DECORATION_HEIGHT);
XSelectInput(display, local_event.xmap.window, SubstructureNotifyMask);
put_text(display, new_win, child_name, "9x15", 10, 10, BlackPixel(display,infos.screen_num), WhitePixel(display, infos.screen_num));
}
}
XFree(child_name);
}
So how to avoid adding of decoration on every window except the main application window (or the popup windows, there is a way to distinguish the type of window? How can i figure it out?)
Second Question
WHen i exit a program the window that is destroyed is just the application window not the parent decoration, how to destroy the current window and also the decoration?
I tried with the following:
void destroy_notify_handler(XEvent local_event, Display *display){
Window window = local_event.xdestroywindow.event;
XDestroyWindow(display, window);
}
But i receive the following error:
Error occurred: BadWindow (invalid Window parameter)
I use event instead of window because it seems that it contains the parent window (i read it from there: http://tronche.com/gui/x/xlib/events/window-state-change/destroy.html)
But even if i use window i have the same problem.
Or maybe i have to destroy the parent window earlier? Maybe during UnMapNotify? But how to understand if the event is launched just because the window is going to be closed or for some other reasons?
Thanks for the help :)
Read EWMH spec and you'll find answers to all questions.
Check "override redirect" window flag
You are trying
to destroy window which is already destroyed. Instead of using
event.xdestroywindow.event window id just delete your decoration
window.
Don't forget to add client window to save set if you are
writing reparenting WM. That way if you kill wm application windows
are not destroyed but reparented back to root window
I don't quite understand what the difference between a window that I create via CreateWindowEx and a "top-level" window.
What is a top level window in win32 programming?
The MSDN entry About Windows offers the following definition:
A window that has no parent, or whose parent is the desktop window, is called a top-level window.
A more practical explanation is given in the blog post A window can have a parent or an owner but not both:
A window can be created as a child window (WS_CHILD set) or a top-level window (WS_CHILD not set).
A top-level window is a window that is not a child window, or has no parent window (which is the same as having the "desktop window" as a parent).
I have an MFC application. In my application if I run on Windows XP it's working fine. But if I run in Windows Vista the MFC dialog hides behind the taskbar.
bool bHide=true;
CRect rectWorkArea = CRect(0,0,0,0);
CRect rectTaskBar = CRect(0,0,0,0);
CWnd* pWnd = CWnd::FindWindow("Shell_TrayWnd", "");
pWnd->ShowWindow(SW_SHOW);
if( bHide )
{ // Code to Hide the System Task Bar
SystemParametersInfo(SPI_GETWORKAREA,0,(LPVOID)&rectWorkArea,0);
if( pWnd )
{
pWnd->GetWindowRect(rectTaskBar);
// rectWorkArea.bottom -= rectTaskBar.Height();
rectWorkArea.bottom += rectTaskBar.Height();//-----to hide taskbar
SystemParametersInfo(SPI_SETWORKAREA,0,(LPVOID)&rectWorkArea,0);
// pWnd->ShowWindow(SW_SHOW);
pWnd->ShowWindow(SW_HIDE); //--to hide taskbar
}
}
I used this code but it hides the taskbar. But I want to show the application above the task bar.
You don't own the taskbar, so you are not supposed to hide it. You have the option to auto-minimize it by the way. You have another option of using secondary monitor without taskbar there.
On the primary monitor your app is given work area, you are being able to locate (judging from the code snippet provided above). It is the best to position your window within this area without interfering with the taskbar, whether it is above or beyond.
If you still feel like making it more like a competition "who is on top" with the task bar, you might want to take a look at SetWindowPos API and window Z-Order.
finally i found the solution , what we want to do is we should add the below code in our oninitdialog,
SetWindowPos(&this->wndTopMost,0,0,0,0,SWP_NOMOVE|SWP_NOSIZE);
the above line is enough to show the mfc dialog on above the taskbar . but sometimes the focus of the dialog get changed looks hanged(no response in dialog) the application.if it occurs put the below code.
SetWindowPos(&this->wndBottom,0,0,0,0,SWP_NOMOVE|SWP_NOSIZE);