class Gdk::DisplayManager
- Gdk::DisplayManager
- GObject::Object
- Reference
- Object
Overview
A singleton object that offers notification when displays appear or disappear.
You can use Gdk::DisplayManager#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.
In the rare case that you need to influence which of the backends
is being used, you can use Gdk#allowed_backends=
. Note
that you need to call this function before initializing GTK.
Backend-specific code
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:
WARNING ⚠️ The following code is in c ⚠️
#ifdef GDK_WINDOWING_X11
if (GDK_IS_X11_DISPLAY (display))
{
// make X11-specific calls here
}
else
#endif
#ifdef GDK_WINDOWING_MACOS
if (GDK_IS_MACOS_DISPLAY (display))
{
// make Quartz-specific calls here
}
else
#endif
g_error ("Unsupported GDK backend");
Defined in:
auto/gdk-4.0/display_manager.crConstructors
-
.new
Initialize a new
DisplayManager
. - .new(*, default_display : Gdk::Display? = nil)
Class Method Summary
-
.g_type : UInt64
Returns the type id (GType) registered in GLib type system.
-
.get : Gdk::DisplayManager
Gets the singleton
GdkDisplayManager
object.
Instance Method Summary
-
#default_display : Gdk::Display?
Gets the default
GdkDisplay
. -
#default_display=(display : Gdk::Display) : Nil
Sets @display as the default display.
- #default_display=(value : Gdk::Display?) : Gdk::Display?
- #display_opened_signal
-
#list_displays : GLib::SList
List all currently open displays.
-
#open_display(name : String) : Gdk::Display?
Opens a display.
Instance methods inherited from class GObject::Object
bind_property(source_property : String, target : GObject::Object, target_property : String, flags : GObject::BindingFlags) : GObject::Binding
bind_property,
bind_property_full(source_property : String, target : GObject::Object, target_property : String, flags : GObject::BindingFlags, transform_to : GObject::Closure, transform_from : GObject::Closure) : GObject::Binding
bind_property_full,
data(key : String) : Pointer(Void)?
data,
finalize
finalize,
freeze_notify : Nil
freeze_notify,
getv(names : Enumerable(String), values : Enumerable(_)) : Nil
getv,
notify(property_name : String) : Nil
notify,
notify_by_pspec(pspec : GObject::ParamSpec) : Nil
notify_by_pspec,
notify_signal
notify_signal,
property(property_name : String, value : _) : Nil
property,
qdata(quark : UInt32) : Pointer(Void)?
qdata,
ref_count
ref_count,
run_dispose : Nil
run_dispose,
set_data(key : String, data : Pointer(Void)?) : Nil
set_data,
set_property(property_name : String, value : _) : Nil
set_property,
steal_data(key : String) : Pointer(Void)?
steal_data,
steal_qdata(quark : UInt32) : Pointer(Void)?
steal_qdata,
thaw_notify : Nil
thaw_notify,
to_unsafe : Pointer(Void)
to_unsafe,
watch_closure(closure : GObject::Closure) : Nil
watch_closure
Constructor methods inherited from class GObject::Object
cast(obj : GObject::Object) : self
cast,
cast?(obj : GObject::Object) : self?
cast?,
new
new,
newv(object_type : UInt64, parameters : Enumerable(GObject::Parameter)) : self
newv
Class methods inherited from class GObject::Object
compat_control(what : UInt64, data : Pointer(Void)?) : UInt64
compat_control,
g_type : UInt64
g_type,
interface_find_property(g_iface : GObject::TypeInterface, property_name : String) : GObject::ParamSpec
interface_find_property,
interface_list_properties(g_iface : GObject::TypeInterface) : Enumerable(GObject::ParamSpec)
interface_list_properties
Constructor Detail
Class Method Detail
Gets the singleton GdkDisplayManager
object.
When called for the first time, this function consults the
GDK_BACKEND
environment variable to find out which of the
supported GDK backends to use (in case GDK has been compiled
with multiple backends).
Applications can use #allowed_backends=
to limit what
backends wil be used.