If iObjectType <> FrameWnd Then lRet = objSurface.Blt(rectBitmap, objBitmap, rectObject, lBltFlags)
If bDrawCaption Then
lOldColor = objSurface.GetForeColor
objSurface.SetForeColor RGB(255, 255, 255)
objSurface.DrawText iCaptionX, iCaptionY, sCaption, False
objSurface.SetForeColor lOldColor
End If
For iLp = 1 To colChildren.Count
colChildren(iLp).DrawObject objSurface
Next iLp
Exit Function
DrawObjectErr:
objErr.WriteLine "Error drawing " & sName & " - " & Err.Description
Exit Function
End Function
As you can see the changes are pretty extensive. The function now has to handle the two new controls and the new Caption member. The RadioBtn is fairly simple since it pretty much acts like the ChkBox inside the class. If you looked at the files included with this project you抣l notice that there抯 no bitmap for the frame object. That抯 because it uses DirectDraw抯 DrawLine function to draw the outline of the frame. Open the framesample.bmp file and zoom in to see how it抯 actually drawn.
We抳e added a function in the class to return a child object. This is necessary to change the RadioBtn抯 ObjectState member when one radio button in a group is clicked:
Public Function GetChild(ByVal sKey As String) As clsWindow
Set GetChild = colChildren(sKey)
End Function
The AddChild method was changed to specify a key when adding a child in order to support this function:
Public Sub AddChild(clsChild As clsWindow)
colChildren.Add clsChild, clsChild.WindowName
End Sub
Take a minute to run the app and play with the new controls. There are a couple of things that could be changed to make the class better but I抣l leave them up to you. Some things could be:
- Add members to allow the font type, size and color to be changed.
- Add a Style member to allow the ChkBox and RadioBtn objects to be graphical similar to the way the VB controls act.
- Change the frame drawing to not draw under the caption.
- Adapt the class to add a LabelWnd object type. This would just use the Caption property
That抯 it for this lesson. I hope it抯 been fun and interesting. The next lesson will attempt to cover listboxes and comboboxes. Hope to see you there.
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