I am trying to find or create an event handler for when my item is dragged outside a form, im using C++ Builder 2007.
You can use Mouse Leave and also use WndProc but this will only work when the user is not dragging (ie has the mouse button pressed too).
Any ideas?
Thanks
VCL drag-and-drop only works within the VCL window, and only when dragging over VCL controls. In order to drag something outside of the window, you have to use OLE drag-and-drop instead by implementing the IDropSource and IDataObject interfaces and pass them to the DoDragDrop() function.
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I'm using raw Win32 and C++ for a project. As I understand it, I am able to superclass Windows controls by retrieving the class information, replacing the procedure, then registering this as a new class and using it when creating a new window. Subclassing is done by replacing the window's procedure after the window is created. The advantage of superclassing is that you are able to process messages before CreateWindow() returns.
I'm looking to see if it's possible to superclass a dialog box created with CreateDialog() because I'd like to use a resource file for the dialog layout. The problem is that I don't know how I would provide my superclass when I create a dialog box. Is it even possible? Any idea how MFC handles this?
If you use an extended dialog box template to create your dialog, you can specify a custom window class as part of the DLGTEMPLATEEX definition.
The dialog manager will create and layout your dialog as normal, and call your window procedure for any dialog messages. You can use the DefDlgProc function to obtain default processing for any dialog messages you don't want to handle yourself.
I am developing an application using the MFC library and I am currently trying to prevent the user accidentally changing one of the combo box controls when they are scrolling the mouse wheel.
I am looking for a solution without deriving a new class from the CComboBox class and preventing the mouse scrolling there.
My understanding of the system is that Windows passes the WM_MOUSEWHEEL message to the Combo box control which handles it (scrolling the combo box) and then this is propagated up the chain of parent controls (so them to my CFormView etc.), which means I cannot prevent the scrolling by capturing the event in my form view.
Does anyone have a solution to this problem? Thanks in advance!
You can always derive a control from CComboBox and trap the WM_MOUSEWHEEL message in the control itself. Then simply use your new derived combo box in your form view.
If you don't want to create a derived class (perhaps it's too big a change for your project), you can subclass the combo box and trap the WM_MOUSEWHEEL there.
Override the PreTranslateMessage handler in the main window class and look for WM_MOUSEWHEEL messages. Compare the pMsg->hwnd handle in PreTranslateMessage handler with the combobox handle, if found, filter the messages away.
Using a Windows 7 touch device Windows shows this little touch-keyboard indicator (tabing this will bring up the touch on screen keyboard) when you tab/focus a textbox or kind of input field (Notepad etc.).
I want to write an application that gets notified when exactly that happens, a textbox (etc.) gets focused (no matter which application).
Are applications informed about focusing in other applications, do I need to hook something?
Is there a way in doing so in c++?
I believe the SetWinEventHook function and specifically the EVENT_OBJECT_FOCUS event is what you are looking for.
From the MSDN description:
An object has received the keyboard focus. The system sends this event for the following user interface elements: list-view control, menu bar, pop-up menu, switch window, tab control, tree view control, and window object. Server applications send this event for their accessible objects.
The hwnd parameter of the WinEventProc callback function identifies the window that receives the keyboard focus.
I use IWebBrowser2 to implement a GUI for my application. I have a custom frameless window which hosts IWebBrowser2. Javascript and window.external I use to communicate with the application.
My question is how to implement moving my host window (with IWebBrowser2 of course)?
I draw a pseudo-Header in html and I need to detect mouse-down event (this is possible)
inside and detect mouse-move event after... and I don't know how can I do it?
Thanks
Don't use IWebBrowser2 directly for this. Instead, use the Win32 API. You can get a HWND with IWebBrowser2::get_HWND. With that, it's easy to subclass its windowproc (via SetWindowLong(GWL_WNDPROC)) and intercept WM_MOUSEMOVE.
I want to make a custom made component (a line chart), that would be used in other applications.
I don't know 2 things:
Where should I use (within component class!) the methods for drawing, like FillRect
or PolyLine? In OnPaint handler that I should define and map it in MESSAGE MAP? Will
it (OnPaint handler) be called from OnPaint handler of the dialog of the application
or where from?
How to connect the component, once it is made, to the test application, which will
for example be dialog based? Where should I instantiate that component? From an
OnCreate method of the MyAppDialog.cpp?
I started coding in MFC few days ago and I'm so confused about it.
Thanks in advance,
Cheers.
Painting the control is handled exactly like it would be if it wasn't a control. Given that you're using MFC, that (at least normally) means you do the drawing in the View class' OnDraw (MFC normally handles OnPaint internally, so you rarely touch it).
Inserting the resulting ActiveX control in the host application will be done like inserting any other ActiveX control. Assuming you're doing your development in Visual Studio, you'll normally do that by opening the dialog, right clicking inside the dialog box, and clicking "Insert ActiveX Control..." in the menu that pops up. Pick your control from the list, and it'll generate a wrapper class for the control and code to create an object of that class as needed. From the viewpoint of the dialog code, it's just there, and you can use it about like any other control.
For create new component in MFC, you must create a class from the window class (CWND),
after that you can have your MessageMap for the component and your methods and also can override CWND::OnDraw method to draw the thing you want.
Before that I suggest you to take a look to device context
http://msdn.microsoft.com/en-us/library/azz5wt61(VS.80).aspx
Good Luck friend.