Windows 7 has the snapping feature which 'snaps' a window to the edges, and changes the one dimension of the window size to match the same dimension of the screen, and then choses another size for the other dimension.
I want to detect that it has happened so that in my WindowStyle.None window with custom chrome, I can implement the proper behavior for double clicking the titlebar.
The snapping does not alter the WindowState, so I cannot detect that it has happened. Since only one dimension of window is set to match the the screen, I can not distinquish between a snapped window and a user resized window. Does Win7 send out a specific message, or include a flag in the WM_xxxx messages when it causes a resize? Is the formula to the other dimension (not the one matching the screen) defined anywhere so that I can check if both dimensions match that of a snapped window?
have you tried using spy++ to watch window messages to see what gets sent in what order? maybe there's an extra mesage in there that windows is using.
Related
I have a ListView with which I'd like to use a context menu that changes depending on selection. I'm making sure that I'm first able to display a menu when the right mouse button has been released (as per normal context menu behaviour).
In my ListView WNDPROC I'm using WM_CONTEXTMENU to display the context menu. The menu however is displayed at the location the cursor began the selection, not at the end.
From the MS documentation:
DefWindowProc generates the WM_CONTEXTMENU message when it processes the WM_RBUTTONUP or WM_NCRBUTTONUP message or when the user types SHIFT+F10. The WM_CONTEXTMENU message is also generated when the user presses and releases the VK_APPS key.
When I inspect the call stack, with a breakpoint in WM_CONTEXTMENU, I see that the message sent prior to WM_CONTEXTMENU was 0x0204 or WM_RBUTTONDOWN containing the coordinates of the cursor at this time. This probably explains the menu location issue, but why would this be happening?
When I hold the RMB down outside of the ListView and release it inside, the context menu still appears and I can see from the call stack that the last message was 0x0205 or WM_RBUTTONUP.
Not sure whether I have something wrong in my code, or I'm not understanding something. Any help on this issue would be greatly appreciated, thanks.
Rather than relying on the WM_RBUTTON(DOWN|UP) messages to determine the mouse coordinates, the WM_CONTEXTMENU's own lParam gives you the mouse's screen coordinates of the message that generated the WM_CONTEXTMENU. If those coordinates are not what you are expecting, you can use GetMessagePos() instead, which will report the screen coordinates at the time WM_CONTEXTMENU was generated. Either way, you can then convert the screen coordinates into ListView client coordinates using ScreenToClient() or MapWindowPoints().
Just be sure you also handle the case where the popup menu is being invoked by the user via keyboard input rather than mouse click. In that case, the lParam of WM_CONTEXTMENU will carry the screen coordinates [x=-1,y=-1], and you can query the ListView for the position of its selected item(s) using LVM_GETITEMPOSITION or LVM_GETITEMRECT as needed, then convert that position to screen coordinates using ClientToScreen() or MapWindowPoints(), and then display the popup menu at that screen location.
I have a WPF application that I want permanently maximised.
The application starts off maximised and that's fine.
I have set the ResizeMode="NoResize" and while this does prevent the window from being resized (by dragging the edges of the window), I find I can drag the title bar down, and the window will resize to a "Restore" state - i.e. partially filling the screen. At this point the window can't be resized (as I'd expect) or maximised once again (even if I drag the title bar back to the top of the screen)
Is there a setting that will just not allow the "restore" functionality and force the Window to always be maximised?
Edit
I've discovered this is actually a window setting, and if I turn off "Arrange windows automatically by dragging them to the corners of the screen" in Settings / System / Multitasking it prevents this (I also needed to remove the ResizeMode="NoResize" funnily enough otherwise dragging the title bar just drags the entire maximised window down).
However, I can still "Restore" it by double-clicking on the title bar. I can maximise once again by doing it again, but I don't want the user to be able to restore the window at all.
Strangely enough, doing it this way ResizeMode="NoResize" lets me restore a maximised window, but not maximise a restored normal window... I'd be happy with the other way around...
I could begin by asking the question outright or by citing my sources (this, this, this, and this) descriptively, but I'll walk you ll through what I'm trying to do instead.
Let's start with a main window. It has its own window class whose hbrBackground is set to COLOR_BTNFACE + 1. Now let's do
EnableThemeDialogTexture(hwnd, ETDT_ENABLE | ETDT_USETABTEXTURE)
so the tab control we're about to add will be drawn with visual styles. (Try Windows XP with the standard Luna theme for best results.) Now let's add a tab control and two tabs.
On the first tab, we create an instance (let's call it container) of a new window class. This window class is going to hold various controls. I could set hbrBackground to COLOR_BTNFACE + 1, but then it will draw over the tab background. So I want this new child window to be transparent. So what I do is
set the class hbrBackground to GetStockObject(HOLLOW_BRUSH)
set container's extended style to WS_EX_TRANSPARENT
set the class WM_ERASEBKGND handler to do SetBkMode((HDC) wParam, TRANSPARENT); return 0; to set the device context and have Windows draw the transparent background.
So far so good, right? I'm not sure if I'm really doing all this correctly, and I'd like this to also be flicker-free, which doesn't seem to happen: when I resize the window (at least in wine) I get either flicker or garbage drawn (even in child controls, somehow!). Windows XP in a VM just shows flicker. I tried tweaking some settings but to no avail.
But wait, now I want to have another control, one that just draws some bitmap data. On the next tab, create another container, then have a third window class area as a child of that. area only draws in the upper-left 100x100 area and has scrollbars; the rest of the window area should be transparent.
Right now, what I have for area is:
the window class hbrBackground set to NULL and styles CS_HREDRAW and CS_VREDRAW set
the extended window style being 0
the WM_ERASEBKGND simply doing return 1;
the WM_PAINT filling the entire update rect with COLOR_BTNFACE + 1 before drawing, and rendering all of it
This is flicker-free, but obviously not transparent. NOW I'm really not sure what to do, because I want the area to be transparent in such a way that it shows the tab control background. Again, I tried tweaking settings to bring them closer to what I tried above with container, but I got either flicker or invalidation leftovers when I tried.
So how do I get both of these custom control types (the container and the drawing area) to be both flicker-free and transparent?
I presently must target Windows XP at a minimum, though if the solution would be easier with Vista+ only I'd be happy to keep that solution on the side in case I ever drop XP support (unfortunately Stack Overflow doesn't let me hand out silver medals...).
Thanks!
To paint your window in a manner that is "flicker free", you will need to paint your window to a bitmap, then copy the bitmap to the destination device context. On Windows XP, you will need to create a bitmap, adjust the origin of the drawing DC and then paint your window. On Vista and later you can use BeginBufferedPaint and its associated routines to do the buffering for you.
Once you have buffered painting working, you can then use WM_PRINTCLIENT to paint your window's parent window into the your drawing DC before you do any actual drawing. Unfortunately, not all windows will support WM_PRINTCLIENT.
You could consider using DrawThemeParentBackground, rather than WM_PRINTCLIENT directly.
Combining these two methods together will leave you with transparent flicker-free drawing.
I need to fit the window's width and height to its content. I'm aware of existance of SizeToClient property of Window, however, if one chooses WidthAndHeight as the value of SizeToClient, window events are fired in invalid way, such that several components raise an exception during Loaded event: "Hwnd of zero is not valid" (for example GlassWindow's SetAeroGlassTransparency from Windows API CodePack).
Is there a workaround? I may calculate the window size manually, but I do not know, how to retrieve the window's chrome sizes (in other words, the real window's content margin sizes).
Details of WPF bug
Best regards -- Spook.
You could use SystemParameters to determine the size of the chrome. For example, SystemParameters.CaptionHeight.
I cannot not find any way to restore the Saved Window Position without seeing the Window jump from its initial default Position to the Restored Position. The problem is that the first time I get access to the Window its already visible to the user. Am I missing something or is there currently no way to do this?
Try adjusting OOB Settings, Width=1, Height=1
It is not ideal, but tolerable.
The window opens very small, then resizes correctly.
I also found that when restoring the window position, you have to set the Width and Height first, then Top and Left. Otherwise there appears to be a bug which sometimes resets the top or left.