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void (*GdkSeatGrabPrepareFunc) (GdkSeat *seat
,GdkSurface *surface
,gpointer user_data
);
Type of the callback used to set up surface
so it can be
grabbed. A typical action would be ensuring the surface is
visible, although there's room for other initialization
actions.
seat |
the GdkSeat being grabbed |
|
surface |
the GdkSurface being grabbed |
|
user_data |
user data passed in |
GdkDisplay *
gdk_seat_get_display (GdkSeat *seat
);
Returns the GdkDisplay this seat belongs to.
GdkGrabStatus gdk_seat_grab (GdkSeat *seat
,GdkSurface *surface
,GdkSeatCapabilities capabilities
,gboolean owner_events
,GdkCursor *cursor
,const GdkEvent *event
,GdkSeatGrabPrepareFunc prepare_func
,gpointer prepare_func_data
);
Grabs the seat so that all events corresponding to the given capabilities
are passed to this application until the seat is ungrabbed with gdk_seat_ungrab()
,
or the surface becomes hidden. This overrides any previous grab on the
seat by this client.
As a rule of thumb, if a grab is desired over GDK_SEAT_CAPABILITY_POINTER
,
all other "pointing" capabilities (eg. GDK_SEAT_CAPABILITY_TOUCH
) should
be grabbed too, so the user is able to interact with all of those while
the grab holds, you should thus use GDK_SEAT_CAPABILITY_ALL_POINTING
most
commonly.
Grabs are used for operations which need complete control over the events corresponding to the given capabilities. For example in GTK this is used for Drag and Drop operations, popup menus and such.
Note that if the event mask of a GdkSurface has selected both button press
and button release events, or touch begin and touch end, then a press event
will cause an automatic grab until the button is released, equivalent to a
grab on the surface with owner_events
set to TRUE
. This is done because most
applications expect to receive paired press and release events.
If you set up anything at the time you take the grab that needs to be cleaned up when the grab ends, you should handle the GdkEventGrabBroken events that are emitted when the grab ends unvoluntarily.
seat |
a GdkSeat |
|
surface |
the GdkSurface which will own the grab |
|
capabilities |
capabilities that will be grabbed |
|
owner_events |
if |
|
cursor |
the cursor to display while the grab is active. If
this is |
[nullable] |
event |
the event that is triggering the grab, or |
[nullable] |
prepare_func |
function to
prepare the surface to be grabbed, it can be |
[nullable][scope call][closure prepare_func_data] |
prepare_func_data |
user data to pass to |
void
gdk_seat_ungrab (GdkSeat *seat
);
Releases a grab added through gdk_seat_grab()
.
GdkSeatCapabilities
gdk_seat_get_capabilities (GdkSeat *seat
);
Returns the capabilities this GdkSeat currently has.
GdkDevice *
gdk_seat_get_pointer (GdkSeat *seat
);
Returns the master device that routes pointer events.
a master GdkDevice with pointer capabilities. This object is owned by GTK and must not be freed.
[transfer none][nullable]
GdkDevice *
gdk_seat_get_keyboard (GdkSeat *seat
);
Returns the master device that routes keyboard events.
a master GdkDevice with keyboard capabilities. This object is owned by GTK and must not be freed.
[transfer none][nullable]
GList * gdk_seat_get_slaves (GdkSeat *seat
,GdkSeatCapabilities capabilities
);
Returns the slave devices that match the given capabilities.
A list of GdkDevices.
The list must be freed with g_list_free()
, the elements are owned
by GDK and must not be freed.
[transfer container][element-type GdkDevice]
GList * gdk_seat_get_master_pointers (GdkSeat *seat
,GdkSeatCapabilities capabilities
);
Returns all master pointers with the given capabilities driven by this seat
.
On most backends this function will return a list with a single element (meaning
that all input devices drive the same onscreen cursor).
In other backends where there can possibly be multiple foci (eg. wayland), this function will return all master GdkDevices that represent these.
typedef struct _GdkSeat GdkSeat;
The GdkSeat struct contains only private fields and should not be accessed directly.
Flags describing the seat capabilities.
Returned by gdk_device_grab()
to indicate success or the reason for the
failure of the grab attempt.
the resource was successfully grabbed. |
||
the resource is actively grabbed by another client. |
||
the resource was grabbed more recently than the specified time. |
||
the grab surface or the |
||
the resource is frozen by an active grab of another client. |
||
the grab failed for some other reason |
“display”
property“display” GdkDisplay *
GdkDisplay of this seat.
Owner: GdkSeat
Flags: Read / Write / Construct Only
“device-added”
signalvoid user_function (GdkSeat *seat, GdkDevice *device, gpointer user_data)
The ::device-added signal is emitted when a new input device is related to this seat.
seat |
the object on which the signal is emitted |
|
device |
the newly added GdkDevice. |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run Last
“device-removed”
signalvoid user_function (GdkSeat *seat, GdkDevice *device, gpointer user_data)
The ::device-removed signal is emitted when an input device is removed (e.g. unplugged).
seat |
the object on which the signal is emitted |
|
device |
the just removed GdkDevice. |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run Last
“tool-added”
signalvoid user_function (GdkSeat *seat, GdkDeviceTool *tool, gpointer user_data)
The ::tool-added signal is emitted whenever a new tool is made known to the seat. The tool may later be assigned to a device (i.e. on proximity with a tablet). The device will emit the “tool-changed” signal accordingly.
A same tool may be used by several devices.
seat |
the object on which the signal is emitted |
|
tool |
the new GdkDeviceTool known to the seat |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run Last
“tool-removed”
signalvoid user_function (GdkSeat *seat, GdkDeviceTool *tool, gpointer user_data)
This signal is emitted whenever a tool is no longer known
to this seat
.
seat |
the object on which the signal is emitted |
|
tool |
the just removed GdkDeviceTool |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run Last