NTool implements the core tool features, which each tool possesses. They are:

• Name - each tool has a name, which can be modified from the Name property. It is important to know that the names of the tools, which reside in the NToolCollection (accessible from the Tools property of the controller) must be unique. In fact the tools collection will not let you add a tool with a duplicate name.
• Enabled/disabled state - in order for tools to activate they need to be enabled. This is controlled by the Enabled property.
• Ability to Activate and Deactivate or Abort - tools can operate in two states - active and inactive. When a tool is active it will receive all view mouse and keyboard events. The transition between these states is performed by the Activate and Deactivate methods. You must call the CanActivate method prior to calling the Activate method and the CanDeactivate method prior to calling the Deactivate method. The actual work performed by tools, which can activate is performed by the Deactivate method. If a tool is active you can always abort it by calling its Abort method.

The type of the tool in general is determined by the interfaces it implements. Currently supported are the following primary types of tools:

• Mouse and Keyboard tools - these are tools, which implement the INMouseEventProcessor and INKeyboardEventProcessor interfaces. The base class for such tools is the NMouseAndKeyboardTool abstract class.
• Drag and Drop tools - these are tools, which implement the INDragDropEventProcessor interface. The base class for such tools is the NDragDropTool abstract class.

Drag tools are Mouse and Keyboard tools, which can be activated and support double pass activation. The base class for such tools is the NDragTool abstract class (derived from NMouseAndKeyboardTool).

Since the controller is assigned to each NView instance, but tools need to know the actual view and document type (drawing or library), the component logically separates the tools by the instancable view type in which they can reside.

In this way all drawing tools derive from the base NDrawingMouseAndKeyboardTool, NDrawingDragDropTool and NDrawingDragTool. Analogously library tools derive from the base NLibraryMouseAndKeyboardTool, NLibraryDragDropTool and NLibraryDragTool.

As already mentioned the tool enabled/disabled state is determined by the value of its Enabled property. The NToolCollection however provides several methods, which help you enable/disable single or multiple tools by their names (that is why the name of the tool must be unique in the context of this collection).

It is important to know that the tool collection maintains a list of the tool names, which are considered to be ambient. The ambient tools are tools, which are by default enabled and are not disabled if you use the SingleEnableTool or SingleEnableTools methods to enable a configuration of tools. For example:

// enable only the rectangle tool, but do not disable the ambient tools
drawingView.Controller.Tools.SingleEnableTool(NDWFR.ToolCreateRectangle);

' enable only the rectangle tool, but do not disable the ambient tools
drawingView.Controller.Tools.SingleEnableTool(NDWFR.ToolCreateRectangle)

Following is a list of the currently available drawing tools:

Following is a list of the currently available library tools: