CodeGuru Staff

Environment: .NET Framework SDK Beta 1, Visual C++ 6 SP4 Introduction : In this article, we’ll take a dip into how the Connection Points Event Handling mechanism in Classic COM Components can be used by .NET applications to receive event Notifications via the COM Interop. What’s interesting here is that, .NET applications can continue to use […]

Many maps come with both a Latitude/Longitude grid for a given datum/ellipsoid as well as a Universal Transverse Mercator (UTM) grid to determine coordinates. There are many applications today that utilize some form of mapping capability. That, along with the increasing need to integrate GPS units (which typically provide UTM coordinates) with applications, made me […]

Overview This article addresses a new implementation of a popular class of Edit Controls I’ve created that I call Multi-Field Edit Controls. A Multi-Field Edit Control is an Edit Control in which the edit box contains multiple fields, each of which may behave as though it were an individual control. I had the idea to […]

Environment: VC6 SP5, NT4 SP6 ( not tested on other OS ) To use this combo box, follow the following steps: Include TooltipComboBox.h, TooltipComboBox.cpp, TooltipListCtrl.h and TooltipListCtrl.cpp in your project. In the resource editor create a droplist combobox. Create a control member variable for the combobox in VC’s classwizard. Include TooltipComboBox.h and replace CComboBox with […]

However, it is not entirely good news. Let’s say that you have written class CMyDialog derived from CDialog that implements some handy features. You derive all your own dialogs from CMyDialog instead of CDialog, so they all have your new features. All is fine with the world. Now you want to add those same nice […]

First, let’s consider how one can go about adding new functionality to a group of classes. The most obvious, brute-force way to add the same functionality to a number of classes is to simple copy and paste the code into each one. This is far from an ideal solution- you only want to write the […]

In general, I am a fan of the way DDX works. It is quite a neat design and has many good points going for it. In particular, it neatly encapsulates the transfer of data between class member variables and dialog controls in a single place, and with a minimum of code. Let us take a […]

I was not too happy with my monolithic approach to the OnCustomdraw handler. There was just too much code in one lump, which is usually a sign that a programmer has not properly factored the design. Each of the cases in the big switch statement performed a distinct action and so should really be in […]

The next step is to add a handler for the NM_CUSTOMDRAW notification message. Usually, to add a handler, one can simply right-click on CListCtrlWithCustomDraw in the class view, or use the WizardBar, and “Add windows message handler.” However, this time there is a catch. NM_CUSTOMDRAW is nowhere to be seen in the list of available […]

The first is the most extreme. You handle the WM_PAINT messages and do all the painting yourself. You get no help at all from Windows with this method. You have to create a device context, determine where and how big your control is, what state it is in, and then draw it all yourself. Most […]

Overview The current MFC combobox class is insufficient. The pop-down choicelists provided for the application I was writing needed to reduce the amount of typing a user must do. The user is given a list of items from which they can choose any combination of selections. When a selection is chosen from the list, it […]

Have you ever had the need to make persistent some settings of your shell extensions? A shell extension is an extremely dynamic object and, as such, its user interface must be visible and affect the way you interact with Explorer. However, some of your users might find it sometimes too intrusive and would like to […]