Nevron .NET Vision
User Interface for .NET / User's Guide / Command Bars / Commands Overview

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    Commands Overview
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    Commands could be considered visualizations of the "Command" abstraction. They are the visual part of the command concept observed by Nevron Command Bars (see Command Bars Overview). They are generic objects carrying information about how to be visualized and information about their current state on the parent. The object model is tree-based - a single command may act as a simple/toggle button or a drop-down menu. It is a command container and is responsible for creating and displaying a menu window to visualize its children commands. Each command container has a Commands property which gives you access to its collection of command objects. Each command has a great number of visual representation properties, all encapsulated in the NCommandProperties class. A command can also behave like a label when specified as non-selectable - it simply displays some information.


    The command itself does not care where it is visualized and what the type of its current parent is. All measuring and drawing is handled by the parent. You are able, however, to specify explicitly that you want to handle measure and paint events. For more information about handling events see Command Behaviour.


    The bridge between command visualizations and common functionality is the NCommandContext object. It is a shareable object among commands, which provides information about how a command is visualized, as well as a common behaviour for all commands that share the context. When assigned a valid context, a command's click event will be delegated to the context. Using this approach you may create a single context and have many commands that share it - they will all expose the same functionality when clicked. For more information about contexts see Command Contexts Overview .

     Predefined Commands

    The following table describes available command types in Nevron UI:

    Command Type Description
    NCommand Base class for all commands. Provides basic implementation of command visualization and behaviour.
    NComboBoxCommand Predefined NControlHostCommand which hosts a NComboBox control.
    NListBoxCommand Predefined NCommand object that contains nested NControlHostCommand which hosts a NListBox control.
    See Also