This part focusses on the Calcium integration of the Task Model.
This project is a Desktop and Silverlight user action management system, with undo, redo, and repeat. Allowing actions to be monitored, and grouped according to a context (such as a UI control), executed sequentially or in parallel, and even to be rolled back on failure.
A 'task' is the term I use to describe application work units,
instigated by the user or the system.
The main features of the task management system provided in this article are:
- Tasks can be undone, redone, and repeated.
- Task execution may be cancelled.
- Composite tasks allow sequential and parallel execution of tasks with automatic rollback on failure of an individual task.
- Tasks can be associated with a context, such as a UserControl, so that the undo, redo, and repeat actions can be, for example, enabled according to UI focus.
- Tasks can be global, having no context association.
- The task system can be wired to ICommands.
- Tasks can be chained, in that one task can use the Task Service to perform another.
- Return to a point in history by specifying an undo point.
- Coherency in the system is preserved by disallowing the execution of tasks outside of the Task Service.
- Task Model compatible with both the Silverlight and Desktop CLRs