Class Responder

Responder base class implemented by objects that want to participate on keyboard and mouse input.
Inheritance
System.Object
Responder
View
Inherited Members
System.Object.Equals(System.Object)
System.Object.Equals(System.Object, System.Object)
System.Object.GetHashCode()
System.Object.GetType()
System.Object.MemberwiseClone()
System.Object.ReferenceEquals(System.Object, System.Object)
System.Object.ToString()
Namespace: Terminal.Gui
Assembly: Terminal.Gui.dll
Syntax
public class Responder

Properties

CanFocus

Gets or sets a value indicating whether this Responder can focus.
Declaration
public virtual bool CanFocus { get; set; }
Property Value
Type Description
System.Boolean true if can focus; otherwise, false.

HasFocus

Gets or sets a value indicating whether this Responder has focus.
Declaration
public virtual bool HasFocus { get; }
Property Value
Type Description
System.Boolean true if has focus; otherwise, false.

Methods

MouseEvent(MouseEvent)

Method invoked when a mouse event is generated
Declaration
public virtual bool MouseEvent(MouseEvent mouseEvent)
Parameters
Type Name Description
MouseEvent mouseEvent Contains the details about the mouse event.
Returns
Type Description
System.Boolean true, if the event was handled, false otherwise.

OnEnter()

Method invoked when a view gets focus.
Declaration
public virtual bool OnEnter()
Returns
Type Description
System.Boolean true, if the event was handled, false otherwise.

OnKeyDown(KeyEvent)

Method invoked when a key is pressed.
Declaration
public virtual bool OnKeyDown(KeyEvent keyEvent)
Parameters
Type Name Description
KeyEvent keyEvent Contains the details about the key that produced the event.
Returns
Type Description
System.Boolean true if the event was handled

OnKeyUp(KeyEvent)

Method invoked when a key is released.
Declaration
public virtual bool OnKeyUp(KeyEvent keyEvent)
Parameters
Type Name Description
KeyEvent keyEvent Contains the details about the key that produced the event.
Returns
Type Description
System.Boolean true if the event was handled

OnLeave()

Method invoked when a view loses focus.
Declaration
public virtual bool OnLeave()
Returns
Type Description
System.Boolean true, if the event was handled, false otherwise.

OnMouseEnter(MouseEvent)

Method invoked when a mouse event is generated for the first time.
Declaration
public virtual bool OnMouseEnter(MouseEvent mouseEvent)
Parameters
Type Name Description
MouseEvent mouseEvent
Returns
Type Description
System.Boolean true, if the event was handled, false otherwise.

OnMouseLeave(MouseEvent)

Method invoked when a mouse event is generated for the last time.
Declaration
public virtual bool OnMouseLeave(MouseEvent mouseEvent)
Parameters
Type Name Description
MouseEvent mouseEvent
Returns
Type Description
System.Boolean true, if the event was handled, false otherwise.

ProcessColdKey(KeyEvent)

This method can be overwritten by views that want to provide accelerator functionality (Alt-key for example), but without interefering with normal ProcessKey behavior.
Declaration
public virtual bool ProcessColdKey(KeyEvent keyEvent)
Parameters
Type Name Description
KeyEvent keyEvent Contains the details about the key that produced the event.
Returns
Type Description
System.Boolean
Remarks

After keys are sent to the subviews on the current view, all the view are processed and the key is passed to the views to allow some of them to process the keystroke as a cold-key.

This functionality is used, for example, by default buttons to act on the enter key. Processing this as a hot-key would prevent non-default buttons from consuming the enter keypress when they have the focus.

ProcessHotKey(KeyEvent)

This method can be overwritten by view that want to provide accelerator functionality (Alt-key for example).
Declaration
public virtual bool ProcessHotKey(KeyEvent kb)
Parameters
Type Name Description
KeyEvent kb
Returns
Type Description
System.Boolean
Remarks

Before keys are sent to the subview on the current view, all the views are processed and the key is passed to the widgets to allow some of them to process the keystroke as a hot-key.

For example, if you implement a button that has a hotkey ok "o", you would catch the combination Alt-o here. If the event is caught, you must return true to stop the keystroke from being dispatched to other views.

ProcessKey(KeyEvent)

If the view is focused, gives the view a chance to process the keystroke.
Declaration
public virtual bool ProcessKey(KeyEvent keyEvent)
Parameters
Type Name Description
KeyEvent keyEvent Contains the details about the key that produced the event.
Returns
Type Description
System.Boolean
Remarks

Views can override this method if they are interested in processing the given keystroke. If they consume the keystroke, they must return true to stop the keystroke from being processed by other widgets or consumed by the widget engine. If they return false, the keystroke will be passed using the ProcessColdKey method to other views to process.

The View implementation does nothing but return false, so it is not necessary to call base.ProcessKey if you derive directly from View, but you should if you derive other View subclasses.