Responder

public protocol Responder

Responder base class implemented by objects that want to participate on keyboard and mouse input.

  • Gets or sets a value indicating whether this Responder can focus.

    Declaration

    Swift

    var canFocus: Bool { get set }

  • Gets or sets a value indicating whether this Responder has focus.

    Declaration

    Swift

    var hasFocus: Bool { get }

  • This method can be overwritten by view that want to provide accelerator functionality (Alt-key for example).

    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.

    Declaration

    Swift

    func processHotKey(event: KeyEvent) -> Bool

  • If the view is focused, gives the view a chance to process the keystroke.

    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.

    Declaration

    Swift

    func processKey(event: KeyEvent) -> Bool

  • This method can be overwritten by views that want to provide accelerator functionality (Alt-key for example), but without interefering with normal ProcessKey behavior.

    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.

    Declaration

    Swift

    func processColdKey(event: KeyEvent) -> Bool

  • Method invoked when a mouse event is generated

    Declaration

    Swift

    func mouseEvent(event: MouseEvent) -> Bool

    Parameters

    event

    Contains the details about the mouse event.

    Return Value

    true if the event was handled, false otherwise

  • Method invoked when a mouse event is generated for the first time.

    Declaration

    Swift

    func mouseEnter(event: MouseEvent) -> Bool

    Parameters

    event

    Contains the details about the mouse event.

    Return Value

    true if the event was handled, false otherwise

  • Method invoked when a mouse event is generated for the last time.

    Declaration

    Swift

    func mouseLeave(event: MouseEvent) -> Bool

    Parameters

    event

    Contains the details about the mouse event.

    Return Value

    true if the event was handled, false otherwise

  • Makes this the first responder object (has the focus)

    Declaration

    Swift

    func becomeFirstResponder() -> Bool

    Return Value

    true if this became the first responder, false if not.

  • Notifies this object that it should no longer have the focus (the first responder)

    Declaration

    Swift

    func resignFirstResponder() -> Bool

    Return Value

    true if this gave up being the first responder, false if not.