Advanced MFC Programming

Chapter 9. Font
CFont *ptrFont;
if(!CDocument::OnNewDocument())return FALSE;
ptrFont=dc.GetCurrentFont();
ptrFont->GetLogFont(&lf);
VERIFY(m_ftDraw.CreateFontIndirect(&lf));
}
return TRUE;
This function will be called when the document is initialized. Within the function, variable m_ftDraw is
used to create a default font. Since the document is always created before the view, creating the font in this
function will guarantee that m_ftDraw will be a valid font when the view is created. This procedure can also
be done in the constructor.
To let the user select different types of fonts, a new command Dialog | Font is added to application’s
mainframe menu IDR_MAINFRAME. The resource ID of this command is ID_DIALOG_FONT and the
corresponding message handler is CGDIDoc::OnDialogFont(), which is implemented as follows:
void CGDIDoc::OnDialogFont()
{
CFontDialog dlg;
LOGFONT lf;
}
if(dlg.DoModal() == IDOK)
{
dlg.GetCurrentFont(&lf);
m_ftDraw.DeleteObject();
VERIFY(m_ftDraw.CreateFontIndirect(&lf));
UpdateAllViews(NULL);
}
After a new font is selected by the user, we delete the old font and create a new one, then call function
CDocument::UpdateAllViews(…) to update the client window.
On the view side, we need to modify function CGDIView::OnDraw(…). In this function, the text string
and the font are retrieved from the document, and are used to draw text in the client window:
void CGDIView::OnDraw(CDC *pDC)
{
CString szText;
CFont *ptrFontOld;
}
CGDIDoc *pDoc=GetDocument();
ASSERT_VALID(pDoc);
szText=pDoc->GetText();
ptrFontOld=pDC->SelectObject(pDoc->GetFont());
pDC->TextOut(0, 0, szText);
pDC->SelectObject(ptrFontOld);
With the above implementation, the application will display a static string. Although we still can not
input any character, the font for drawing the text can be changed through executing Dialog | Font
command.
9.5 One Line Text Editor, Step 2: Adding Caret
Caret Functions
Caret is a very important feature for text editor, it indicates the current editing position. This makes the
interface more user friendly. Because there are many types of fonts in the system, and for each font, the
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