Derived class OnPaint() question

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Hi guys, I am creating a CEdit derived class and I notice the overriden OnPaint() will not get called if I don't use Create() to create the control. If I draw a CEdit control on my dialog from Resource Editor and uses it by a pointer (assuming the CEdit derived class is CMyEdit:

	pMyEdit = (CMyEdit *)GetDlgItem(IDC_MY_EDIT);
	pMyEdit->SetFont(&editFont, TRUE);
	pMyEdit->SetWindowText(_T("Testing"));

the OnPaint() is never called. But the following will do:

	pMyEdit->Create(dwStyle, Rect, this, IDC_MY_EDIT);

Why is that? What does it mean when a control has been created from the resource editor, compared to created manually in the code? Also, is there a member function for CEdit that can be overriden to let redraw of only the content (text) and background colour? Pretty much the same as DrawItem() for CListCtrl. Thanks alot

valikac

The two member functions SetFont() and SetWindowText() send different messages to the edit window rather than WM_PAINT. For example, SetWindowText() sends WM_SETTEXT. You can override OnDraw() in the edit view. Kuphryn

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Thanks kuphryn, So it seems that for CEdit control not all display related operations will go through WM_PAINT (i.e. in MFC, OnPaint()) at the end. I found it a bit odd: using different ways when they all lead to the CEdit control's display needing to be refreshed eventually. I happened to find this post[^] which the guy asks exactly what I was looking. The control is the CEdit type, so I won't be able to overriding OnDraw(). I need something that has the appearance and functionalities of the CEdit and which then I can have/create a general function to customise its output(display) content (e.g. text, background colours), once for all. Thanks.

valikac

It is possible to override OnDraw() in an edit view. What type of CEdit object is it? Kuphryn

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Hi Kuphryn, I creat and use the CEdit control from the resource view, it's Edit Control by the name. I'd use a CEdit derived class with it, like in my original post. And I'm hoping to handle the text content painting operation myself. I looked on MSDN and I couldn't find possible OnDraw() for CEdit, can you kindly give me an example? Thanks again.

valikac

Okay. In that case, add a message handler to WM_PAINT in the CEdit subclass. Kuphryn

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Hi Kuphryn, perhaps my original post wasn't not clear. That's exactly what I was doing in the first place, to add the WM_PAINT handler by overriding OnPaint() in the sub-class. The problem I am having is that OnPaint() is never called if I use the sub-class directly with the control I created from the resource view. But if I explicitly create the control in run-time using Create(), OnPant() gets called no problem. You can look my first post for the example. Thanks.