Detailed Description

GlgControl provides callback methods that are invoked to handle various events in the control's drawing. The callbacks may be overridden by control's subclasses to implement custom event processing logic.

AddListener can also be used to add GLG listeners that will handle events as an alternative to subclassing.

Functions
virtual Object	AddListener (GlgCallbackType listener_type, Object listener)
	Adds an event listener to the control. More...

virtual void	HCallback (GlgObject viewport)
	H callback. More...

virtual void	HierarchyCallback (GlgObject top_viewport, GlgHierarchyData hierarchy_info)
	Hierarchy callback. More...

virtual void	InputCallback (GlgObject vp, GlgObject message_obj)
	Input callback. More...

virtual void	ReadyCallback (GlgObject viewport)
	Ready callback. More...

virtual void	SelectCallback (GlgObject vp, Object[] name_array, int button)
	Select callback. More...

virtual void	Trace2Callback (GlgObject top_viewport, GlgTraceData trace_info)
	This method is invoked to handle any events in the control's drawing and may be overridden by control's subclasses to implement custom event handling logic. More...

virtual void	TraceCallback (GlgObject top_viewport, GlgTraceData trace_info)
	Trace callback. More...

virtual void	VCallback (GlgObject viewport)
	V callback. More...

Function Documentation

◆ AddListener()

virtual Object AddListener	(	GlgCallbackType	listener_type,
		Object	listener
	)

virtual

Adds an event listener to the control.

Only a single event listener for each listener type is enabled. Setting a new event listener overrides any previous settings. Hierarchy listener must be attached before loading the control's drawing.

By default, the control itself is used as a listener for all GLG events; adding a listener disables the corresponding event-handling callback of the control (for example, adding the INPUT_CB listener disables the control's InputCallback). Therefore, the application must use only one type of the event handling: either a control's callback or a listener.

The control's callback method is usually used for applications which subclass the control to provide different event-handling functionality for derived classes.

The control's C# events are handled independently and are not affected if a corresponding listener is added: both the listener and an event handler will be invoked.

Parameters

listener_type

The type of listener to add. May be one of the following:

listener

The listener to be added. Must implement one of the following interfaces that match the listener_type parameter:

A null value may be used to remove a listener for the events specified by the listener_type parameter.

Returns: Previous listener of the specified type.

◆ HCallback()

virtual void HCallback ( GlgObject viewport )

virtual

H callback.

This method is invoked after the control's drawing has been loaded, but before its object hierarchy has been setup.

The method can be used for setting initial parameters of the loaded drawing before its hierarchy has been setup.

Parameters

viewport The top viewport object of the control's drawing.

Implements GlgHListener.

◆ HierarchyCallback()

virtual void HierarchyCallback	(	GlgObject	top_viewport,
		GlgHierarchyData	hierarchy_info
	)

virtual

Hierarchy callback.

is used to get access to the drawing to be displayed in the SubWindow and SubDrawing objects before the drawing is displayed.

This method is invoked when a SubWindow object in the control's drawing loads its template drawing, or when a SubDrawing loads its template. The method is invokes several times at different stages of the template setup and may used to configure the SubWindow and SubDrawing instances before they are displayed.

The method may be overridden by control's subclasses to implement custom instance setup logic.

A Hierarchy listener can be added using AddListener as an alternative to subclassing.

Parameters

top_viewport	The top-level viewport object.
hierarchy_info	GlgHierarchyData object containing information about the subdrawing that triggered the callback. See GlgHierarchyData for more information.

The method is invoked with the same parameters as the HierarchyCallback method of GlgHierarchyListener. See HierarchyCallback for more information.

Implements GlgHierarchyListener.

◆ InputCallback()

virtual void InputCallback	(	GlgObject	vp,
		GlgObject	message_obj
	)

virtual

Input callback.

This method is invoked to handle user interaction with input objects, as well as to perform object selection and action processing, and may be overridden by control's subclasses to implement custom interaction logic.

An Input listener can be added using AddListener as an alternative to subclassing.

Parameters

vp	The top-level viewport object.
message_obj	Message object containing input event information.

The method is invoked with the same parameters as the InputCallback method of GlgInputListener. See InputCallback for more information.

Implements GlgInputListener.

◆ ReadyCallback()

virtual void ReadyCallback ( GlgObject viewport )

virtual

Ready callback.

This method is invoked when the control has finished initializing, loading and displaying its drawing. This method may be overridden by control's subclasses to provide a custom control initialization logic.

The IsReady method can also be used to query the control's readiness.

Parameters

viewport The top viewport object of the loaded drawing.

Implements GlgReadyListener.

◆ SelectCallback()

virtual void SelectCallback	(	GlgObject	vp,
		Object[]	name_array,
		int	button
	)

virtual

Select callback.

This method provides a simplified name-based interface to handle object selection. It is invoked when objects are selected with the mouse and may be overridden by control's subclasses to implement custom selection logic.

A Select listener can be added using AddListener as an alternative to subclassing.

InputCallback provides an alternative callback that provides more elaborate selection information.

Parameters

vp	The top-level viewport object.
name_array	A null-terminated list of names of all named objects selected with the mouse, or null if no objects were selected.
button	The mouse button that was pressed to select objects.

The method is invoked with the same parameters as the SelectCallback method of GlgSelectListener. See SelectCallback for more information.

Implements GlgSelectListener.

◆ Trace2Callback()

virtual void Trace2Callback	(	GlgObject	top_viewport,
		GlgTraceData	trace_info
	)

virtual

This method is invoked to handle any events in the control's drawing and may be overridden by control's subclasses to implement custom event handling logic.

The method is similar to the TraceCallback, but is invoked after the event has been processed.

A Trace2 listener can be added using AddListener as an alternative to subclassing.

Parameters

top_viewport	The top-level viewport object.
trace_info	A GlgTraceData object containing detailed event information. See GlgTraceData for more information.

The method is invoked with the same parameters as the TraceCallback method of GlgTraceListener. See TraceCallback for more information.

◆ TraceCallback()

virtual void TraceCallback	(	GlgObject	top_viewport,
		GlgTraceData	trace_info
	)

virtual

Trace callback.

This method is invoked to handle any events in the control's drawing and may be overridden by control's subclasses to implement custom event handling logic. The method is invoked before the event has been processed.

A Trace listener can be added using AddListener as an alternative to subclassing.

Parameters

top_viewport	The top-level viewport object.
trace_info	A GlgTraceData object containing detailed event information. See GlgTraceData for more information.

The method is invoked with the same parameters as the TraceCallback method of GlgTraceListener. See TraceCallback for more information.

Implements GlgTraceListener.

◆ VCallback()

virtual void VCallback ( GlgObject viewport )

virtual

V callback.

This method is invoked after the object hierarchy of the control's drawing has been setup.

The method can be used for setting initial parameters of the loaded drawing after its hierarchy has been setup, but before the drawing is displayed.

Parameters

viewport The top viewport object of the control's drawing.

Implements GlgVListener.

Detailed Description

Functions

Function Documentation

◆ AddListener()

◆ HCallback()

◆ HierarchyCallback()

◆ InputCallback()

◆ ReadyCallback()

◆ SelectCallback()

◆ Trace2Callback()

◆ TraceCallback()

◆ VCallback()