DisplayManagerProtocol

public protocol DisplayManagerProtocol : ObjectProtocol

The DisplayManagerProtocol protocol exposes the methods and properties of an underlying GdkDisplayManager instance. The default implementation of these can be found in the protocol extension below. For a concrete class that implements these methods and properties, see DisplayManager. Alternatively, use DisplayManagerRef as a lighweight, unowned reference if you already have an instance you just want to use.

The purpose of the GdkDisplayManager singleton object is to offer notification when displays appear or disappear or the default display changes.

You can use gdk_display_manager_get() to obtain the GdkDisplayManager singleton, but that should be rarely necessary. Typically, initializing GTK+ opens a display that you can work with without ever accessing the GdkDisplayManager.

The GDK library can be built with support for multiple backends. The GdkDisplayManager object determines which backend is used at runtime.

When writing backend-specific code that is supposed to work with multiple GDK backends, you have to consider both compile time and runtime. At compile time, use the GDK_WINDOWING_X11, GDK_WINDOWING_WIN32 macros, etc. to find out which backends are present in the GDK library you are building your application against. At runtime, use type-check macros like GDK_IS_X11_DISPLAY() to find out which backend is in use:

Backend-specific code ##

(C Language Example):

#ifdef GDK_WINDOWING_X11
  if (GDK_IS_X11_DISPLAY (display))
    {
      // make X11-specific calls here
    }
  else
#endif
#ifdef GDK_WINDOWING_QUARTZ
  if (GDK_IS_QUARTZ_DISPLAY (display))
    {
      // make Quartz-specific calls here
    }
  else
#endif
  g_error ("Unsupported GDK backend");
  • ptr

    Untyped pointer to the underlying GdkDisplayManager instance.

    Declaration

    Swift

    var ptr: UnsafeMutableRawPointer! { get }
  • display_manager_ptr Default implementation

    Typed pointer to the underlying GdkDisplayManager instance.

    Default Implementation

    Return the stored, untyped pointer as a typed pointer to the GdkDisplayManager instance.

    Declaration

    Swift

    var display_manager_ptr: UnsafeMutablePointer<GdkDisplayManager>! { get }
  • Required Initialiser for types conforming to DisplayManagerProtocol

    Declaration

    Swift

    init(raw: UnsafeMutableRawPointer)

DisplayManager Class

  • Bind a DisplayManagerPropertyName source property to a given target object.

    Declaration

    Swift

    @discardableResult
    @inlinable
    func bind<Q, T>(property source_property: DisplayManagerPropertyName, to target: T, _ target_property: Q, flags f: BindingFlags = .default, transformFrom transform_from: @escaping GLibObject.ValueTransformer = { $0.transform(destValue: $1) }, transformTo transform_to: @escaping GLibObject.ValueTransformer = { $0.transform(destValue: $1) }) -> BindingRef! where Q : PropertyNameProtocol, T : ObjectProtocol

    Parameters

    source_property

    the source property to bind

    target

    the target object to bind to

    target_property

    the target property to bind to

    flags

    the flags to pass to the Binding

    transform_from

    ValueTransformer to use for forward transformation

    transform_to

    ValueTransformer to use for backwards transformation

    Return Value

    binding reference or nil in case of an error

  • get(property:) Extension method

    Get the value of a DisplayManager property

    Declaration

    Swift

    @inlinable
    func get(property: DisplayManagerPropertyName) -> GLibObject.Value

    Parameters

    property

    the property to get the value for

    Return Value

    the value of the named property

  • set(property:value:) Extension method

    Set the value of a DisplayManager property. Note that this will only have an effect on properties that are writable and not construct-only!

    Declaration

    Swift

    @inlinable
    func set(property: DisplayManagerPropertyName, value v: GLibObject.Value)

    Parameters

    property

    the property to get the value for

    Return Value

    the value of the named property

DisplayManager signals

  • Connect a Swift signal handler to the given, typed DisplayManagerSignalName signal

    Declaration

    Swift

    @discardableResult
    @inlinable
    func connect(signal s: DisplayManagerSignalName, flags f: ConnectFlags = ConnectFlags(0), handler h: @escaping SignalHandler) -> Int

    Parameters

    signal

    The signal to connect

    flags

    The connection flags to use

    data

    A pointer to user data to provide to the callback

    destroyData

    A GClosureNotify C function to destroy the data pointed to by userData

    handler

    The Swift signal handler (function or callback) to invoke on the given signal

    Return Value

    The signal handler ID (always greater than 0 for successful connections)

  • Connect a C signal handler to the given, typed DisplayManagerSignalName signal

    Declaration

    Swift

    @discardableResult
    @inlinable
    func connect(signal s: DisplayManagerSignalName, flags f: ConnectFlags = ConnectFlags(0), data userData: gpointer!, destroyData destructor: GClosureNotify? = nil, signalHandler h: @escaping GCallback) -> Int

    Parameters

    signal

    The signal to connect

    flags

    The connection flags to use

    data

    A pointer to user data to provide to the callback

    destroyData

    A GClosureNotify C function to destroy the data pointed to by userData

    signalHandler

    The C function to be called on the given signal

    Return Value

    The signal handler ID (always greater than 0 for successful connections)

  • The display-opened signal is emitted when a display is opened.

    Note

    This represents the underlying display-opened signal

    Declaration

    Swift

    @discardableResult
    @inlinable
    func onDisplayOpened(flags: ConnectFlags = ConnectFlags(0), handler: @escaping (_ unownedSelf: DisplayManagerRef, _ display: DisplayRef) -> Void) -> Int

    Parameters

    flags

    Flags

    unownedSelf

    Reference to instance of self

    display

    the opened display

    handler

    The signal handler to call Run the given callback whenever the displayOpened signal is emitted

  • displayOpenedSignal Extension method

    Typed display-opened signal for using the connect(signal:) methods

    Declaration

    Swift

    static var displayOpenedSignal: DisplayManagerSignalName { get }
  • The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.

    Note that getting this signal doesn’t itself guarantee that the value of the property has actually changed. When it is emitted is determined by the derived GObject class. If the implementor did not create the property with G_PARAM_EXPLICIT_NOTIFY, then any call to g_object_set_property() results in notify being emitted, even if the new value is the same as the old. If they did pass G_PARAM_EXPLICIT_NOTIFY, then this signal is emitted only when they explicitly call g_object_notify() or g_object_notify_by_pspec(), and common practice is to do that only when the value has actually changed.

    This signal is typically used to obtain change notification for a single property, by specifying the property name as a detail in the g_signal_connect() call, like this: (C Language Example):

    g_signal_connect (text_view->buffer, "notify::paste-target-list",
                      G_CALLBACK (gtk_text_view_target_list_notify),
                      text_view)
    

    It is important to note that you must use canonical parameter names as detail strings for the notify signal.

    Note

    This represents the underlying notify::default-display signal

    Declaration

    Swift

    @discardableResult
    @inlinable
    func onNotifyDefaultDisplay(flags: ConnectFlags = ConnectFlags(0), handler: @escaping (_ unownedSelf: DisplayManagerRef, _ pspec: ParamSpecRef) -> Void) -> Int

    Parameters

    flags

    Flags

    unownedSelf

    Reference to instance of self

    pspec

    the GParamSpec of the property which changed.

    handler

    The signal handler to call Run the given callback whenever the notifyDefaultDisplay signal is emitted

  • notifyDefaultDisplaySignal Extension method

    Typed notify::default-display signal for using the connect(signal:) methods

    Declaration

    Swift

    static var notifyDefaultDisplaySignal: DisplayManagerSignalName { get }

DisplayManager Class: DisplayManagerProtocol extension (methods and fields)