Package org.gnome.gdk

Class Display

java.lang.Object

org.javagi.base.ProxyInstance

org.gnome.gobject.TypeInstance

org.gnome.gobject.GObject

org.gnome.gdk.Display

All Implemented Interfaces:

Proxy

@Generated("io.github.jwharm.JavaGI")
public class Display
extends GObject

A representation of a workstation.

Their purpose are two-fold:

• To manage and provide information about input devices (pointers, keyboards, etc)
• To manage and provide information about output devices (monitors, projectors, etc)

Most of the input device handling has been factored out into separate Seat objects. Every display has a one or more seats, which can be accessed with getDefaultSeat() and listSeats().

Output devices are represented by Monitor objects, which can be accessed with getMonitorAtSurface(org.gnome.gdk.Surface) and similar APIs.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Display.Builder<B extends Display.Builder<B>>	Inner class implementing a builder pattern to construct a GObject with properties.
static interface	Display.ClosedCallback	Functional interface declaration of the ClosedCallback callback.
static interface	Display.OpenedCallback	Functional interface declaration of the OpenedCallback callback.
static interface	Display.SeatAddedCallback	Functional interface declaration of the SeatAddedCallback callback.
static interface	Display.SeatRemovedCallback	Functional interface declaration of the SeatRemovedCallback callback.
static interface	Display.SettingChangedCallback	Functional interface declaration of the SettingChangedCallback callback.

Nested classes/interfaces inherited from class org.gnome.gobject.GObject

GObject.NotifyCallback, GObject.ObjectClass

Constructor Summary

Constructors

Constructor	Description
Display()	Creates a new Display.
Display(MemorySegment address)	Create a Display proxy instance for the provided memory address.

Method Summary

Modifier and Type	Method	Description
protected Display	asParent()	Returns this instance as if it were its parent type.
void	beep()	Emits a short beep on this Display
static Display.Builder<? extends Display.Builder>	builder()	A Display.Builder object constructs a Display with the specified properties.
void	close()	Closes the connection to the windowing system for the given display.
GLContext	createGlContext()	Creates a new GdkGLContext for the GdkDisplay.
boolean	deviceIsGrabbed(Device device)	Returns true if there is an ongoing grab on device for display.
void	emitClosed(boolean isError)	Emits the "closed" signal.
void	emitOpened()	Emits the "opened" signal.
void	emitSeatAdded(@Nullable Seat seat)	Emits the "seat-added" signal.
void	emitSeatRemoved(@Nullable Seat seat)	Emits the "seat-removed" signal.
void	emitSettingChanged(String setting)	Emits the "setting-changed" signal.
void	flush()	Flushes any requests queued for the windowing system.
AppLaunchContext	getAppLaunchContext()	Returns a GdkAppLaunchContext suitable for launching applications on the given display.
Clipboard	getClipboard()	Gets the clipboard used for copy/paste operations.
static @Nullable Display	getDefault()	Gets the default GdkDisplay.
@Nullable Seat	getDefaultSeat()	Returns the default GdkSeat for this display.
DmabufFormats	getDmabufFormats()	Returns the dma-buf formats that are supported on this display.
@Nullable Monitor	getMonitorAtSurface(Surface surface)	Gets the monitor in which the largest area of surface resides.
ListModel	getMonitors()	Gets the list of monitors associated with this display.
String	getName()	Gets the name of the display.
Clipboard	getPrimaryClipboard()	Gets the clipboard used for the primary selection.
boolean	getSetting(String name, Value value)	Retrieves a desktop-wide setting such as double-click time for the display.
@Nullable String	getStartupNotificationId()	Deprecated.
static @Nullable Type	getType()	Get the GType of the Display class
boolean	isClosed()	Finds out if the display has been closed.
boolean	isComposited()	Returns whether surfaces can reasonably be expected to have their alpha channel drawn correctly on the screen.
boolean	isRgba()	Returns whether surfaces on this this Display are created with an alpha channel.
List<Seat>	listSeats()	Returns the list of seats known to display.
boolean	mapKeycode(int keycode, @Nullable Out<KeymapKey[]> keys, @Nullable Out<int[]> keyvals)	Returns the keyvals bound to keycode.
boolean	mapKeyval(int keyval, @Nullable Out<KeymapKey[]> keys)	Obtains a list of keycode/group/level combinations that will generate keyval.
void	notifyStartupComplete(String startupId)	Deprecated. Using Toplevel.setStartupId(java.lang.String) is sufficient
SignalConnection<Display.ClosedCallback>	onClosed(Display.ClosedCallback handler)	Emitted when the connection to the windowing system for display is closed.
SignalConnection<Display.OpenedCallback>	onOpened(Display.OpenedCallback handler)	Emitted when the connection to the windowing system for display is opened.
SignalConnection<Display.SeatAddedCallback>	onSeatAdded(Display.SeatAddedCallback handler)	Emitted whenever a new seat is made known to the windowing system.
SignalConnection<Display.SeatRemovedCallback>	onSeatRemoved(Display.SeatRemovedCallback handler)	Emitted whenever a seat is removed by the windowing system.
SignalConnection<Display.SettingChangedCallback>	onSettingChanged(Display.SettingChangedCallback handler)	Emitted whenever a setting changes its value.
static @Nullable Display	open(@Nullable String displayName)	Opens a display.
boolean	prepareGl()	Checks that OpenGL is available for this Display and ensures that it is properly initialized.
void	putEvent(Event event)	Deprecated. This function is only useful in very special situations and should not be used by applications.
boolean	supportsInputShapes()	Returns true if the display supports input shapes.
boolean	supportsShadowWidth()	Returns whether it's possible for a surface to draw outside of the window area.
void	sync()	Flushes any requests queued for the windowing system and waits until all requests have been handled.
boolean	translateKey(int keycode, Set<ModifierType> state, int group, @Nullable Out<Integer> keyval, @Nullable Out<Integer> effectiveGroup, @Nullable Out<Integer> level, @Nullable Out<Set<ModifierType>> consumed)	Translates the contents of a GdkEventKey into a keyval, effective group, and level.
boolean	translateKey(int keycode, ModifierType state, int group, @Nullable Out<Integer> keyval, @Nullable Out<Integer> effectiveGroup, @Nullable Out<Integer> level, @Nullable Out<ModifierType> consumed)	Translates the contents of a GdkEventKey into a keyval, effective group, and level.

Methods inherited from class org.gnome.gobject.GObject

addToggleRef, addWeakPointer, bindProperty, bindProperty, bindProperty, bindPropertyFull, bindPropertyFull, bindPropertyWithClosures, bindPropertyWithClosures, compatControl, connect, connect, connect, constructed, disconnect, dispatchPropertiesChanged, dispose, dupData, dupQdata, emit, emitNotify, finalize_, forceFloating, freezeNotify, get, getData, getMemoryLayout, getProperty, getProperty, getProperty, getQdata, getv, interfaceFindProperty, interfaceInstallProperty, interfaceListProperties, isFloating, newInstance, newInstance, newv, notify, notify, notifyByPspec, onNotify, ref, refSink, removeToggleRef, removeWeakPointer, replaceData, replaceQdata, runDispose, set, setData, setDataFull, setProperty, setProperty, setProperty, setQdata, setQdataFull, setv, stealData, stealQdata, takeRef, thawNotify, unref, watchClosure, weakRef, weakUnref, withProperties

Methods inherited from class org.gnome.gobject.TypeInstance

callParent, callParent, cast, getPrivate, readGClass, writeGClass

Methods inherited from class org.javagi.base.ProxyInstance

equals, handle, hashCode

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Display

public Display(MemorySegment address)

Create a Display proxy instance for the provided memory address.

Parameters:

address - the memory address of the native object

Display

public Display()

Creates a new Display.

Method Details

getType

public static @Nullable Type getType()

Get the GType of the Display class

Returns:

the GType

asParent

protected Display asParent()

Returns this instance as if it were its parent type. This is mostly synonymous to the Java super keyword, but will set the native typeclass function pointers to the parent type. When overriding a native virtual method in Java, "chaining up" with super.methodName() doesn't work, because it invokes the overridden function pointer again. To chain up, call asParent().methodName(). This will call the native function pointer of this virtual method in the typeclass of the parent type.

Overrides:

asParent in class GObject

getDefault

public static @Nullable Display getDefault()

Gets the default GdkDisplay.

This is a convenience function for:

gdk_display_manager_get_default_display (gdk_display_manager_get ())

Returns:

a GdkDisplay, or null if there is no default display

open

public static @Nullable Display open(@Nullable String displayName)

Opens a display.

If opening the display fails, NULL is returned.

Parameters:

displayName - the name of the display to open

Returns:

a GdkDisplay

beep

public void beep()

Emits a short beep on this Display

close

public void close()

Closes the connection to the windowing system for the given display.

This cleans up associated resources.

createGlContext

public GLContext createGlContext()
                          throws GErrorException

Creates a new GdkGLContext for the GdkDisplay.

The context is disconnected from any particular surface or surface and cannot be used to draw to any surface. It can only be used to draw to non-surface framebuffers like textures.

If the creation of the GdkGLContext failed, error will be set. Before using the returned GdkGLContext, you will need to call GLContext.makeCurrent() or GLContext.realize().

Returns:

the newly created GdkGLContext

Throws:

GErrorException - see GError

Since:

4.6

deviceIsGrabbed

public boolean deviceIsGrabbed(Device device)

Returns true if there is an ongoing grab on device for display.

Parameters:

device - a GdkDevice

Returns:

true if there is a grab in effect for device.

flush

public void flush()

Flushes any requests queued for the windowing system.

This happens automatically when the main loop blocks waiting for new events, but if your application is drawing without returning control to the main loop, you may need to call this function explicitly. A common case where this function needs to be called is when an application is executing drawing commands from a thread other than the thread where the main loop is running.

This is most useful for X11. On windowing systems where requests are handled synchronously, this function will do nothing.

getAppLaunchContext

public AppLaunchContext getAppLaunchContext()

Returns a GdkAppLaunchContext suitable for launching applications on the given display.

Returns:

a new GdkAppLaunchContext for this Display

getClipboard

public Clipboard getClipboard()

Gets the clipboard used for copy/paste operations.

Returns:

the display's clipboard

getDefaultSeat

public @Nullable Seat getDefaultSeat()

Returns the default GdkSeat for this display.

Note that a display may not have a seat. In this case, this function will return null.

Returns:

the default seat.

getDmabufFormats

public DmabufFormats getDmabufFormats()

Returns the dma-buf formats that are supported on this display.

GTK may use OpenGL or Vulkan to support some formats. Calling this function will then initialize them if they aren't yet.

The formats returned by this function can be used for negotiating buffer formats with producers such as v4l, pipewire or GStreamer.

To learn more about dma-bufs, see DmabufTextureBuilder.

This function is threadsafe. It can be called from any thread.

Returns:

a GdkDmabufFormats object

Since:

4.14

getMonitorAtSurface

public @Nullable Monitor getMonitorAtSurface(Surface surface)

Gets the monitor in which the largest area of surface resides.

Parameters:

surface - a GdkSurface

Returns:

the monitor with the largest overlap with surface

getMonitors

public ListModel getMonitors()

Gets the list of monitors associated with this display.

Subsequent calls to this function will always return the same list for the same display.

You can listen to the GListModel::items-changed signal on this list to monitor changes to the monitor of this display.

Returns:

a GListModel of GdkMonitor

getName

public String getName()

Gets the name of the display.

Returns:

a string representing the display name. This string is owned by GDK and should not be modified or freed.

getPrimaryClipboard

public Clipboard getPrimaryClipboard()

Gets the clipboard used for the primary selection.

On backends where the primary clipboard is not supported natively, GDK emulates this clipboard locally.

Returns:

the primary clipboard

getSetting

public boolean getSetting(String name,
 Value value)

Retrieves a desktop-wide setting such as double-click time for the display.

Parameters:

name - the name of the setting

value - location to store the value of the setting

Returns:

true if the setting existed and a value was stored in value, false otherwise

getStartupNotificationId

@Deprecated
public @Nullable String getStartupNotificationId()

Deprecated.

Gets the startup notification ID for a Wayland display, or null if no ID has been defined.

Returns:

the startup notification ID for this Display

isClosed

public boolean isClosed()

Finds out if the display has been closed.

Returns:

true if the display is closed.

isComposited

public boolean isComposited()

Returns whether surfaces can reasonably be expected to have their alpha channel drawn correctly on the screen.

Check isRgba() for whether the display supports an alpha channel.

On X11 this function returns whether a compositing manager is compositing on display.

On modern displays, this value is always true.

Returns:

Whether surfaces with RGBA visuals can reasonably be expected to have their alpha channels drawn correctly on the screen.

isRgba

public boolean isRgba()

Returns whether surfaces on this this Display are created with an alpha channel.

Even if a true is returned, it is possible that the surface’s alpha channel won’t be honored when displaying the surface on the screen: in particular, for X an appropriate windowing manager and compositing manager must be running to provide appropriate display. Use isComposited() to check if that is the case.

On modern displays, this value is always true.

Returns:

true if surfaces are created with an alpha channel or false if the display does not support this functionality.

listSeats

public List<Seat> listSeats()

Returns the list of seats known to display.

Returns:

the list of seats known to the GdkDisplay

mapKeycode

public boolean mapKeycode(int keycode,
 @Nullable Out<KeymapKey[]> keys,
 @Nullable Out<int[]> keyvals)

Returns the keyvals bound to keycode.

The Nth GdkKeymapKey in keys is bound to the Nth keyval in keyvals.

When a keycode is pressed by the user, the keyval from this list of entries is selected by considering the effective keyboard group and level.

Free the returned arrays with g_free().

Parameters:

keycode - a keycode

keys - return location for array of GdkKeymapKey

keyvals - return location for array of keyvals

Returns:

true if there were any entries

mapKeyval

public boolean mapKeyval(int keyval,
 @Nullable Out<KeymapKey[]> keys)

Obtains a list of keycode/group/level combinations that will generate keyval.

Groups and levels are two kinds of keyboard mode; in general, the level determines whether the top or bottom symbol on a key is used, and the group determines whether the left or right symbol is used.

On US keyboards, the shift key changes the keyboard level, and there are no groups. A group switch key might convert a keyboard between Hebrew to English modes, for example.

GdkEventKey contains a group field that indicates the active keyboard group. The level is computed from the modifier mask.

The returned array should be freed with g_free().

Parameters:

keyval - a keyval, such as GDK_KEY_a, GDK_KEY_Up, GDK_KEY_Return, etc.

keys - return location for an array of GdkKeymapKey

Returns:

true if keys were found and returned

notifyStartupComplete

@Deprecated
public void notifyStartupComplete(String startupId)

Deprecated.

Using Toplevel.setStartupId(java.lang.String) is sufficient

Indicates to the GUI environment that the application has finished loading, using a given identifier.

GTK will call this function automatically for GtkWindow with custom startup-notification identifier unless gtk_window_set_auto_startup_notification() is called to disable that feature.

Parameters:

startupId - a startup-notification identifier, for which notification process should be completed

prepareGl

public boolean prepareGl()
                  throws GErrorException

Checks that OpenGL is available for this Display and ensures that it is properly initialized. When this fails, an error will be set describing the error and this function returns false.

Note that even if this function succeeds, creating a GdkGLContext may still fail.

This function is idempotent. Calling it multiple times will just return the same value or error.

You never need to call this function, GDK will call it automatically as needed. But you can use it as a check when setting up code that might make use of OpenGL.

Returns:

true if the display supports OpenGL

Throws:

GErrorException - see GError

Since:

4.4

putEvent

@Deprecated
public void putEvent(Event event)

Deprecated.

This function is only useful in very special situations and should not be used by applications.

Adds the given event to the event queue for display.

Parameters:

event - a GdkEvent

supportsInputShapes

public boolean supportsInputShapes()

Returns true if the display supports input shapes.

This means that Surface.setInputRegion(org.freedesktop.cairo.Region) can be used to modify the input shape of surfaces on display.

On modern displays, this value is always true.

Returns:

true if surfaces with modified input shape are supported

supportsShadowWidth

public boolean supportsShadowWidth()

Returns whether it's possible for a surface to draw outside of the window area.

If true is returned the application decides if it wants to draw shadows. If false is returned, the compositor decides if it wants to draw shadows.

Returns:

true if surfaces can draw shadows or false if the display does not support this functionality.

Since:

4.14

sync

public void sync()

Flushes any requests queued for the windowing system and waits until all requests have been handled.

This is often used for making sure that the display is synchronized with the current state of the program. Calling sync() before org.gnome.gdk.Display#errorTrapPop makes sure that any errors generated from earlier requests are handled before the error trap is removed.

This is most useful for X11. On windowing systems where requests are handled synchronously, this function will do nothing.

translateKey

public boolean translateKey(int keycode,
 Set<ModifierType> state,
 int group,
 @Nullable Out<Integer> keyval,
 @Nullable Out<Integer> effectiveGroup,
 @Nullable Out<Integer> level,
 @Nullable Out<Set<ModifierType>> consumed)

Translates the contents of a GdkEventKey into a keyval, effective group, and level.

Modifiers that affected the translation and are thus unavailable for application use are returned in consumedModifiers.

The effectiveGroup is the group that was actually used for the translation; some keys such as Enter are not affected by the active keyboard group. The level is derived from state.

consumedModifiers gives modifiers that should be masked out from state when comparing this key press to a keyboard shortcut. For instance, on a US keyboard, the plus symbol is shifted, so when comparing a key press to a <Control>plus accelerator <Shift> should be masked out.

This function should rarely be needed, since GdkEventKey already contains the translated keyval. It is exported for the benefit of virtualized test environments.

Parameters:

keycode - a keycode

state - a modifier state

group - active keyboard group

keyval - return location for keyval

effectiveGroup - return location for effective group

level - return location for level

consumed - return location for modifiers that were used to determine the group or level

Returns:

true if there was a keyval bound to keycode/state/group.

translateKey

public boolean translateKey(int keycode,
 ModifierType state,
 int group,
 @Nullable Out<Integer> keyval,
 @Nullable Out<Integer> effectiveGroup,
 @Nullable Out<Integer> level,
 @Nullable Out<ModifierType> consumed)

Translates the contents of a GdkEventKey into a keyval, effective group, and level.

Modifiers that affected the translation and are thus unavailable for application use are returned in consumedModifiers.

The effectiveGroup is the group that was actually used for the translation; some keys such as Enter are not affected by the active keyboard group. The level is derived from state.

consumedModifiers gives modifiers that should be masked out from state when comparing this key press to a keyboard shortcut. For instance, on a US keyboard, the plus symbol is shifted, so when comparing a key press to a <Control>plus accelerator <Shift> should be masked out.

This function should rarely be needed, since GdkEventKey already contains the translated keyval. It is exported for the benefit of virtualized test environments.

Parameters:

keycode - a keycode

state - a modifier state

group - active keyboard group

keyval - return location for keyval

effectiveGroup - return location for effective group

level - return location for level

consumed - return location for modifiers that were used to determine the group or level

Returns:

true if there was a keyval bound to keycode/state/group.

onClosed

public SignalConnection<Display.ClosedCallback> onClosed(Display.ClosedCallback handler)

Emitted when the connection to the windowing system for display is closed.

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

See Also:

• Display.ClosedCallback.run(boolean)

emitClosed

public void emitClosed(boolean isError)

Emits the "closed" signal. See onClosed(org.gnome.gdk.Display.ClosedCallback).

onOpened

public SignalConnection<Display.OpenedCallback> onOpened(Display.OpenedCallback handler)

Emitted when the connection to the windowing system for display is opened.

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

See Also:

• Display.OpenedCallback.run()

emitOpened

public void emitOpened()

Emits the "opened" signal. See onOpened(org.gnome.gdk.Display.OpenedCallback).

onSeatAdded

public SignalConnection<Display.SeatAddedCallback> onSeatAdded(Display.SeatAddedCallback handler)

Emitted whenever a new seat is made known to the windowing system.

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

See Also:

• Display.SeatAddedCallback.run(org.gnome.gdk.Seat)

emitSeatAdded

public void emitSeatAdded(@Nullable Seat seat)

Emits the "seat-added" signal. See onSeatAdded(org.gnome.gdk.Display.SeatAddedCallback).

onSeatRemoved

public SignalConnection<Display.SeatRemovedCallback> onSeatRemoved(Display.SeatRemovedCallback handler)

Emitted whenever a seat is removed by the windowing system.

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

See Also:

• Display.SeatRemovedCallback.run(org.gnome.gdk.Seat)

emitSeatRemoved

public void emitSeatRemoved(@Nullable Seat seat)

Emits the "seat-removed" signal. See onSeatRemoved(org.gnome.gdk.Display.SeatRemovedCallback).

onSettingChanged

public SignalConnection<Display.SettingChangedCallback> onSettingChanged(Display.SettingChangedCallback handler)

Emitted whenever a setting changes its value.

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

See Also:

• Display.SettingChangedCallback.run(java.lang.String)

emitSettingChanged

public void emitSettingChanged(String setting)

Emits the "setting-changed" signal. See onSettingChanged(org.gnome.gdk.Display.SettingChangedCallback).

builder

public static Display.Builder<? extends Display.Builder> builder()

A Display.Builder object constructs a Display with the specified properties. Use the various set...() methods to set properties, and finish construction with Display.Builder.build().

Returns:

the builder object