In this chapter you will learn how to use an Outlook COM addin to extend tasks to create a hierarchical task system. The Task Management System addin lets you add child tasks to an existing task, and uses a custom task pane to display related tasks in a treeview control.
Outlook tasks have always been isolated items, only suitable for use as a to-do list. A task can be linked to a contact but you can't relate one task to another to provide for parent-child relationships, something necessary for use as a task manager. The Task Management System adds the basic essentials for a task manager and can be used as the basis for a more sophisticated set of task management features.
The code is provided as two addin projects, one in VB.NET and the other in C#. Both are specific to Outlook 2007, using the
PropertyAccessor object and the Ribbon, which aren't available in earlier versions of Outlook. Both projects require Visual Studio 2005 and Framework 2.0 or higher.
The projects are available for download from the Wrox web site (
www.wrox.com) as well as from
www.slovaktech.com. These projects also include setup projects configured to create debug installations. Shims used to provide unique application domains for shared addins are not provided for the projects.
The user interface for adding child tasks and displaying related tasks is provided by a custom Ribbon tab with two controls, shown in Figure 10-1.
The Show Related Tasks ...