I'm just getting started with wxWidgets, so please be kind on me.
How can i disable, that a frame appears around a Button, when the mouse enters the Button. Or is the another/easier way to make a Picture click-able ?
You might be looking for wxBitmapButton which allows you to set different bitmaps for its different states (focused, pressed, ...).
If not, then you really need to explain more clearly what are you after.
Related
I'm working on a Qt class project. We're supposed to develop an application like Microsoft Paint. Now I don't know how to enlarge a selected part of an image. Actually I don't even know how to "select" an area. You know, just like that on the desktop of Windows, you press the left button of the mouse and than move it, a dashed-line rectangle will show up. I hope to move or zoom in/out this particular area.
Any help will be appreciated, thanks!
It could be done by using mouse events. Here's example that might be useful to you:https://doc.qt.io/qt-5/qtwidgets-widgets-scribble-example.html
(this is not MFC)
I created a window which is transparent and covers the whole screen. However, I want it to be merely an overlay, not accepting any clicks or keyboard presses anywhere, only covering parts of the screen (and even there, don't accept input). It should be always on top (works so far) and should not block input to the windows below it. Is there a way to set this somewhere or a way to workaround this?
EnableWindow(hWnd, false); does not do what I want (obviously).
Ah, sorry for posting. Finally found it out!
WS_EX_TRANSPARENT is the style you want to add.
I need a GroupBox control for something else that showing it in application's window. That's why I want to disable the frame surrounding it (or at least make it invisible by, for example, drawing it with the color that matches with window's background). Both are harder than I thought though, I've been loking for the solution everywhere and found nothing. I don't want to use anything as straightforward as painting over it in WM_PAINT-case in window procedure because there will be that annoying sparkling when I move the window.
I'm running out of ideas, tried a few things on my own, none worked. Anyone have some tips?
I have implemented my custom button inheriting from CButton and drawing it by using uxtheme.dll (DrawThemeBackground with BP_PUSHBUTTON).
Everything works fine but I have two statuses (Normal and Pressed) which Hot status is the same. It means when the user places the cursor over the button it is drawn alike regardless the button status (Pressed or not).
This is a bit confusing to the user and I would like to change the way the button is drawn in Pressed & Hot status. Does anybody know a way?
I have also thought about custumizing the whole drawing but the buttons use gradients, borders, shadows, etc. So it is not easy to achive the same look&feel drawing everything by myself. Is there a way to find the source code of the dll or know how to do it?
Thanks in advance.
Javier
Note: I think I could be able to achive what I want to do by using CMFCButton and overriding the OnDraw method. Let the control draw the button on OnDrawBorder and then drawing the inside button myself. But I need to know how the control draws the inside button when pressed. It is a gradient and I can't guess how it's done. Does anybody have a clue?
In answer to your second question, if you derive from CMFCButton instead of CButton you can override OnDraw() or OnDrawText() instead of the usual DrawItem(). That way the default button background will be drawn, and then your drawing code is executed.
The only way I know of to really tackle this is to use 'custom draw', rather than 'owner draw'. Custom draw came in with Windows 2000, but is only used by button controls with comctrl32 6.0 (so Windows XP onwards), isn't very clearly documented, and isn't something MFC goes out of its way to support.
Anyway, the good thing about custom draw is that it lets you hook in at various points in the drawing process, unlike owner draw, which makes you deal with the whole thing. Have a look in MSDN at the NM_CUSTOMDRAW notification message.
For the other part of your problem, detecting the 'hot' state, the easiest way to do this is to use WM_MOUSEMOVE messages and the TrackMouseEvent() function to track whether the mouse is over your button.
Unfortunately this is a bit of a vague answer: the amount of code you need to demonstrate a button that uses custom draw is a bit too much to type into these answer boxes! I do have a project that demonstrates such techniques, using a custom draw button (falling back to owner draw on older Windows versions) that adds a little arrow to the button. You can have a look at the source code by getting
Windows_UI_source.zip
Open it and have a look at the "DropArrowButton" class. The important bit is the OnCustomDraw() handler and its helper function DrawControl(): these get called at the various button drawing phases, and use UxTheme to draw the control appropriately.
I finally figured out how to achive what I want to do. It's pretty easy indeed.
I use two calls to DrawThemeBackground. The first one with PBS_PRESSED and the second one with state PBS_HOT. Then I make a ExcludeClipRect to avoid from drawing over the center of the button.
Something like this:
DrawThemeBackground( hTheme,
pCustomDraw->hdc,
BP_PUSHBUTTON,
PBS_PRESSED,
&pCustomDraw->rc,
NULL);
CDC *pDC = CDC::FromHandle(pCustomDraw->hdc);
CRect rectClient;
GetClientRect(rectClient);
CRect rectInternal = rectClient;
rectInternal.DeflateRect(4,4);
pDC->SelectClipRgn(NULL);
pDC->ExcludeClipRect(&rectInternal);
DrawThemeBackground( hTheme,
pCustomDraw->hdc,
BP_PUSHBUTTON,
PBS_HOT,
&pCustomDraw->rc,
NULL);
pDC->SelectClipRgn(NULL);
Of course this is not the whole code but I think is enough to make my point.
Thanks.
I'm trying to implement some drag and drop functionality for a material system being developed at my work. Part of this system includes a 'Material Library' which acts as a repository, divided into groups, of saved materials on the user's hard drive.
As part of some UI polish, I was hoping to implement a 'highlight' type feature. When dragging and dropping, windows that you can legally drop a material onto will very subtly change color to improve feedback to the user that this is a valid action.
I am changing the bar with 'Basic Materials' (Just a CWnd with a CStatic) from having a medium gray background when unhighlighed to a blue background when hovered over. It all works well, the OnDragEnter and OnDragExit messages seem robust and set a flag indicating the highlight status. Then in OnCtrlColor I do this:
if (!m_bHighlighted) {
pDC->FillSolidRect(0, 0, m_SizeX, kGroupHeaderHeight, kBackgroundColour);
}
else {
pDC->FillSolidRect(0, 0, m_SizeX, kGroupHeaderHeight, kHighlightedBackgroundColour);
}
However, as you can see in the screenshot, the painting 'glitches' below the dragged object, leaving the original gray in place. It looks really ugly and basically spoils the whole effect.
Is there any way I can get around this?
Remote debugging is a godsend for debugging visual issues. It's a pain to set up, but having a VM ready for remote debugging will pay off for sure.
What I like to do is set a ton of breakpoints in my paint handling, as well as in the framework paint code itself. This allows you to effectively "freeze frame" the painting without borking it up by flipping into devenv. This way you can get the true picture of who's painting in what order, and where you've got the chance to break in a fill that rect the way you need to.
It almost looks like the CStatic doesn't know that it needs to repaint itself, so the background color of the draggable object is left behind. Maybe try to invalidate the CStatic, and see if that helps at all?
Thanks for the answers guys, ajryan, you seem to always come up with help for my questions so extra thanks.
Thankfully this time the answer was fairly straightforward....
ImageList_DragShowNolock(FALSE);
m_pDragDropTargetWnd->SendMessage(WM_USER_DRAG_DROP_OBJECT_DRAG_ENTER, (WPARAM)pDragDropObject, (LPARAM)(&dragDropPoint));
ImageList_DragShowNolock(TRUE);
This turns off the drawing of the dragged image, then sends a message to the window being entered to repaint in a highlighted state, then finally redraws the drag image over the top. Seems to have done the trick.