Copyright | Will Thompson Iñaki García Etxebarria and Jonas Platte |
---|---|
License | LGPL-2.1 |
Maintainer | Iñaki García Etxebarria (garetxe@gmail.com) |
Safe Haskell | None |
Language | Haskell2010 |
Gesture
is the base object for gesture recognition, although this
object is quite generalized to serve as a base for multi-touch gestures,
it is suitable to implement single-touch and pointer-based gestures (using
the special Nothing
EventSequence
value for these).
The number of touches that a Gesture
need to be recognized is controlled
by the Gesture
:n-points
property, if a gesture is keeping track of less
or more than that number of sequences, it won't check wether the gesture
is recognized.
As soon as the gesture has the expected number of touches, the gesture will
run the Gesture
::check
signal regularly on input events until the gesture
is recognized, the criteria to consider a gesture as "recognized" is left to
Gesture
subclasses.
A recognized gesture will then emit the following signals:
Gesture
::begin
when the gesture is recognized.- A number of
Gesture
::update
, whenever an input event is processed. Gesture
::end
when the gesture is no longer recognized.
Event propagation
In order to receive events, a gesture needs to either set a propagation phase
through eventControllerSetPropagationPhase
, or feed those manually
through eventControllerHandleEvent
.
In the capture phase, events are propagated from the toplevel down to the target widget, and gestures that are attached to containers above the widget get a chance to interact with the event before it reaches the target.
After the capture phase, GTK+ emits the traditional Widget
::button-press-event
,
Widget
::button-release-event
, Widget
::touch-event
, etc signals. Gestures
with the PropagationPhaseTarget
phase are fed events from the default Widget
::event
handlers.
In the bubble phase, events are propagated up from the target widget to the toplevel, and gestures that are attached to containers above the widget get a chance to interact with events that have not been handled yet.
Whenever input interaction happens, a single event may trigger a cascade of
GtkGestures
, both across the parents of the widget receiving the event and
in parallel within an individual widget. It is a responsibility of the
widgets using those gestures to set the state of touch sequences accordingly
in order to enable cooperation of gestures around the GdkEventSequences
triggering those.
Within a widget, gestures can be grouped through gestureGroup
,
grouped gestures synchronize the state of sequences, so calling
gestureSetSequenceState
on one will effectively propagate
the state throughout the group.
By default, all sequences start out in the GTK_EVENT_SEQUENCE_NONE
state,
sequences in this state trigger the gesture event handler, but event
propagation will continue unstopped by gestures.
If a sequence enters into the GTK_EVENT_SEQUENCE_DENIED
state, the gesture
group will effectively ignore the sequence, letting events go unstopped
through the gesture, but the "slot" will still remain occupied while
the touch is active.
If a sequence enters in the GTK_EVENT_SEQUENCE_CLAIMED
state, the gesture
group will grab all interaction on the sequence, by:
- Setting the same sequence to
GTK_EVENT_SEQUENCE_DENIED
on every other gesture group within the widget, and every gesture on parent widgets in the propagation chain. - calling
Gesture
::cancel
on every gesture in widgets underneath in the propagation chain. - Stopping event propagation after the gesture group handles the event.
Note: if a sequence is set early to GTK_EVENT_SEQUENCE_CLAIMED
on
GDK_TOUCH_BEGIN
/GDK_BUTTON_PRESS
(so those events are captured before
reaching the event widget, this implies GTK_PHASE_CAPTURE
), one similar
event will emulated if the sequence changes to GTK_EVENT_SEQUENCE_DENIED
.
This way event coherence is preserved before event propagation is unstopped
again.
Sequence states can't be changed freely, see gestureSetSequenceState
to know about the possible lifetimes of a EventSequence
.
Touchpad gestures
On the platforms that support it, Gesture
will handle transparently
touchpad gesture events. The only precautions users of Gesture
should do
to enable this support are:
- Enabling
EventMaskTouchpadGestureMask
on theirGdkWindows
- If the gesture has
PropagationPhaseNone
, ensuring events of typeEventTypeTouchpadSwipe
andEventTypeTouchpadPinch
are handled by theGesture
Synopsis
- newtype Gesture = Gesture (ManagedPtr Gesture)
- class GObject o => IsGesture o
- toGesture :: (MonadIO m, IsGesture o) => o -> m Gesture
- noGesture :: Maybe Gesture
- gestureGetBoundingBox :: (HasCallStack, MonadIO m, IsGesture a) => a -> m (Bool, Rectangle)
- gestureGetBoundingBoxCenter :: (HasCallStack, MonadIO m, IsGesture a) => a -> m (Bool, Double, Double)
- gestureGetDevice :: (HasCallStack, MonadIO m, IsGesture a) => a -> m (Maybe Device)
- gestureGetGroup :: (HasCallStack, MonadIO m, IsGesture a) => a -> m [Gesture]
- gestureGetLastEvent :: (HasCallStack, MonadIO m, IsGesture a) => a -> Maybe EventSequence -> m (Maybe Event)
- gestureGetLastUpdatedSequence :: (HasCallStack, MonadIO m, IsGesture a) => a -> m (Maybe EventSequence)
- gestureGetPoint :: (HasCallStack, MonadIO m, IsGesture a) => a -> Maybe EventSequence -> m (Bool, Double, Double)
- gestureGetSequenceState :: (HasCallStack, MonadIO m, IsGesture a) => a -> EventSequence -> m EventSequenceState
- gestureGetSequences :: (HasCallStack, MonadIO m, IsGesture a) => a -> m [EventSequence]
- gestureGetWindow :: (HasCallStack, MonadIO m, IsGesture a) => a -> m (Maybe Window)
- gestureGroup :: (HasCallStack, MonadIO m, IsGesture a, IsGesture b) => a -> b -> m ()
- gestureHandlesSequence :: (HasCallStack, MonadIO m, IsGesture a) => a -> Maybe EventSequence -> m Bool
- gestureIsActive :: (HasCallStack, MonadIO m, IsGesture a) => a -> m Bool
- gestureIsGroupedWith :: (HasCallStack, MonadIO m, IsGesture a, IsGesture b) => a -> b -> m Bool
- gestureIsRecognized :: (HasCallStack, MonadIO m, IsGesture a) => a -> m Bool
- gestureSetSequenceState :: (HasCallStack, MonadIO m, IsGesture a) => a -> EventSequence -> EventSequenceState -> m Bool
- gestureSetState :: (HasCallStack, MonadIO m, IsGesture a) => a -> EventSequenceState -> m Bool
- gestureSetWindow :: (HasCallStack, MonadIO m, IsGesture a, IsWindow b) => a -> Maybe b -> m ()
- gestureUngroup :: (HasCallStack, MonadIO m, IsGesture a) => a -> m ()
- constructGestureNPoints :: IsGesture o => Word32 -> IO (GValueConstruct o)
- getGestureNPoints :: (MonadIO m, IsGesture o) => o -> m Word32
- clearGestureWindow :: (MonadIO m, IsGesture o) => o -> m ()
- constructGestureWindow :: (IsGesture o, IsWindow a) => a -> IO (GValueConstruct o)
- getGestureWindow :: (MonadIO m, IsGesture o) => o -> m (Maybe Window)
- setGestureWindow :: (MonadIO m, IsGesture o, IsWindow a) => o -> a -> m ()
- type C_GestureBeginCallback = Ptr () -> Ptr EventSequence -> Ptr () -> IO ()
- type GestureBeginCallback = EventSequence -> IO ()
- afterGestureBegin :: (IsGesture a, MonadIO m) => a -> GestureBeginCallback -> m SignalHandlerId
- genClosure_GestureBegin :: GestureBeginCallback -> IO Closure
- mk_GestureBeginCallback :: C_GestureBeginCallback -> IO (FunPtr C_GestureBeginCallback)
- noGestureBeginCallback :: Maybe GestureBeginCallback
- onGestureBegin :: (IsGesture a, MonadIO m) => a -> GestureBeginCallback -> m SignalHandlerId
- wrap_GestureBeginCallback :: GestureBeginCallback -> C_GestureBeginCallback
- type C_GestureCancelCallback = Ptr () -> Ptr EventSequence -> Ptr () -> IO ()
- type GestureCancelCallback = EventSequence -> IO ()
- afterGestureCancel :: (IsGesture a, MonadIO m) => a -> GestureCancelCallback -> m SignalHandlerId
- genClosure_GestureCancel :: GestureCancelCallback -> IO Closure
- mk_GestureCancelCallback :: C_GestureCancelCallback -> IO (FunPtr C_GestureCancelCallback)
- noGestureCancelCallback :: Maybe GestureCancelCallback
- onGestureCancel :: (IsGesture a, MonadIO m) => a -> GestureCancelCallback -> m SignalHandlerId
- wrap_GestureCancelCallback :: GestureCancelCallback -> C_GestureCancelCallback
- type C_GestureEndCallback = Ptr () -> Ptr EventSequence -> Ptr () -> IO ()
- type GestureEndCallback = EventSequence -> IO ()
- afterGestureEnd :: (IsGesture a, MonadIO m) => a -> GestureEndCallback -> m SignalHandlerId
- genClosure_GestureEnd :: GestureEndCallback -> IO Closure
- mk_GestureEndCallback :: C_GestureEndCallback -> IO (FunPtr C_GestureEndCallback)
- noGestureEndCallback :: Maybe GestureEndCallback
- onGestureEnd :: (IsGesture a, MonadIO m) => a -> GestureEndCallback -> m SignalHandlerId
- wrap_GestureEndCallback :: GestureEndCallback -> C_GestureEndCallback
- type C_GestureSequenceStateChangedCallback = Ptr () -> Ptr EventSequence -> CUInt -> Ptr () -> IO ()
- type GestureSequenceStateChangedCallback = EventSequence -> EventSequenceState -> IO ()
- afterGestureSequenceStateChanged :: (IsGesture a, MonadIO m) => a -> GestureSequenceStateChangedCallback -> m SignalHandlerId
- genClosure_GestureSequenceStateChanged :: GestureSequenceStateChangedCallback -> IO Closure
- mk_GestureSequenceStateChangedCallback :: C_GestureSequenceStateChangedCallback -> IO (FunPtr C_GestureSequenceStateChangedCallback)
- noGestureSequenceStateChangedCallback :: Maybe GestureSequenceStateChangedCallback
- onGestureSequenceStateChanged :: (IsGesture a, MonadIO m) => a -> GestureSequenceStateChangedCallback -> m SignalHandlerId
- wrap_GestureSequenceStateChangedCallback :: GestureSequenceStateChangedCallback -> C_GestureSequenceStateChangedCallback
- type C_GestureUpdateCallback = Ptr () -> Ptr EventSequence -> Ptr () -> IO ()
- type GestureUpdateCallback = EventSequence -> IO ()
- afterGestureUpdate :: (IsGesture a, MonadIO m) => a -> GestureUpdateCallback -> m SignalHandlerId
- genClosure_GestureUpdate :: GestureUpdateCallback -> IO Closure
- mk_GestureUpdateCallback :: C_GestureUpdateCallback -> IO (FunPtr C_GestureUpdateCallback)
- noGestureUpdateCallback :: Maybe GestureUpdateCallback
- onGestureUpdate :: (IsGesture a, MonadIO m) => a -> GestureUpdateCallback -> m SignalHandlerId
- wrap_GestureUpdateCallback :: GestureUpdateCallback -> C_GestureUpdateCallback
Exported types
Memory-managed wrapper type.
Instances
GObject Gesture Source # | |
Defined in GI.Gtk.Objects.Gesture gobjectType :: Gesture -> IO GType # | |
IsObject Gesture Source # | |
Defined in GI.Gtk.Objects.Gesture | |
IsEventController Gesture Source # | |
Defined in GI.Gtk.Objects.Gesture | |
IsGesture Gesture Source # | |
Defined in GI.Gtk.Objects.Gesture |
class GObject o => IsGesture o Source #
Instances
(GObject a, (UnknownAncestorError Gesture a :: Constraint)) => IsGesture a Source # | |
Defined in GI.Gtk.Objects.Gesture | |
IsGesture Gesture Source # | |
Defined in GI.Gtk.Objects.Gesture | |
IsGesture GestureDrag Source # | |
Defined in GI.Gtk.Objects.GestureDrag | |
IsGesture GestureSingle Source # | |
Defined in GI.Gtk.Objects.GestureSingle | |
IsGesture GestureZoom Source # | |
Defined in GI.Gtk.Objects.GestureZoom | |
IsGesture GestureSwipe Source # | |
Defined in GI.Gtk.Objects.GestureSwipe | |
IsGesture GestureStylus Source # | |
Defined in GI.Gtk.Objects.GestureStylus | |
IsGesture GestureRotate Source # | |
Defined in GI.Gtk.Objects.GestureRotate | |
IsGesture GesturePan Source # | |
Defined in GI.Gtk.Objects.GesturePan | |
IsGesture GestureMultiPress Source # | |
Defined in GI.Gtk.Objects.GestureMultiPress | |
IsGesture GestureLongPress Source # | |
Defined in GI.Gtk.Objects.GestureLongPress |
Methods
getBoundingBox
gestureGetBoundingBox Source #
If there are touch sequences being currently handled by gesture
,
this function returns True
and fills in rect
with the bounding
box containing all active touches. Otherwise, False
will be
returned.
Note: This function will yield unexpected results on touchpad
gestures. Since there is no correlation between physical and
pixel distances, these will look as if constrained in an
infinitely small area, rect
width and height will thus be 0
regardless of the number of touchpoints.
Since: 3.14
getBoundingBoxCenter
getDevice
getGroup
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> m [Gesture] | Returns: The list
of |
Returns all gestures in the group of gesture
Since: 3.14
getLastEvent
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> Maybe EventSequence |
|
-> m (Maybe Event) | Returns: The last event from |
Returns the last event that was processed for sequence
.
Note that the returned pointer is only valid as long as the sequence
is still interpreted by the gesture
. If in doubt, you should make
a copy of the event.
getLastUpdatedSequence
gestureGetLastUpdatedSequence Source #
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> m (Maybe EventSequence) | Returns: The last updated sequence |
Returns the EventSequence
that was last updated on gesture
.
Since: 3.14
getPoint
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> Maybe EventSequence |
|
-> m (Bool, Double, Double) | Returns: |
If sequence
is currently being interpreted by gesture
, this
function returns True
and fills in x
and y
with the last coordinates
stored for that event sequence. The coordinates are always relative to the
widget allocation.
Since: 3.14
getSequenceState
gestureGetSequenceState Source #
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> EventSequence |
|
-> m EventSequenceState | Returns: The sequence state in |
Returns the sequence
state, as seen by gesture
.
Since: 3.14
getSequences
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> m [EventSequence] | Returns: A list
of |
Returns the list of GdkEventSequences
currently being interpreted
by gesture
.
Since: 3.14
getWindow
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> m (Maybe Window) | Returns: the user defined window, or |
Returns the user-defined window that receives the events
handled by gesture
. See gestureSetWindow
for more
information.
Since: 3.14
group
:: (HasCallStack, MonadIO m, IsGesture a, IsGesture b) | |
=> a |
|
-> b |
|
-> m () |
Adds gesture
to the same group than groupGesture
. Gestures
are by default isolated in their own groups.
When gestures are grouped, the state of GdkEventSequences
is kept in sync for all of those, so calling gestureSetSequenceState
,
on one will transfer the same value to the others.
Groups also perform an "implicit grabbing" of sequences, if a
EventSequence
state is set to GTK_EVENT_SEQUENCE_CLAIMED
on one group,
every other gesture group attached to the same Widget
will switch the
state for that sequence to GTK_EVENT_SEQUENCE_DENIED
.
Since: 3.14
handlesSequence
gestureHandlesSequence Source #
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> Maybe EventSequence |
|
-> m Bool | Returns: |
Returns True
if gesture
is currently handling events corresponding to
sequence
.
Since: 3.14
isActive
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> m Bool | Returns: |
Returns True
if the gesture is currently active.
A gesture is active meanwhile there are touch sequences
interacting with it.
Since: 3.14
isGroupedWith
:: (HasCallStack, MonadIO m, IsGesture a, IsGesture b) | |
=> a |
|
-> b |
|
-> m Bool | Returns: whether the gestures are grouped |
Returns True
if both gestures pertain to the same group.
Since: 3.14
isRecognized
setSequenceState
gestureSetSequenceState Source #
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> EventSequence |
|
-> EventSequenceState |
|
-> m Bool | Returns: |
Sets the state of sequence
in gesture
. Sequences start
in state GTK_EVENT_SEQUENCE_NONE
, and whenever they change
state, they can never go back to that state. Likewise,
sequences in state GTK_EVENT_SEQUENCE_DENIED
cannot turn
back to a not denied state. With these rules, the lifetime
of an event sequence is constrained to the next four:
- None
- None → Denied
- None → Claimed
- None → Claimed → Denied
Note: Due to event handling ordering, it may be unsafe to
set the state on another gesture within a Gesture
::begin
signal handler, as the callback might be executed before
the other gesture knows about the sequence. A safe way to
perform this could be:
static void first_gesture_begin_cb (GtkGesture *first_gesture, GdkEventSequence *sequence, gpointer user_data) { gtk_gesture_set_sequence_state (first_gesture, sequence, GTK_EVENT_SEQUENCE_CLAIMED); gtk_gesture_set_sequence_state (second_gesture, sequence, GTK_EVENT_SEQUENCE_DENIED); } static void second_gesture_begin_cb (GtkGesture *second_gesture, GdkEventSequence *sequence, gpointer user_data) { if (gtk_gesture_get_sequence_state (first_gesture, sequence) == GTK_EVENT_SEQUENCE_CLAIMED) gtk_gesture_set_sequence_state (second_gesture, sequence, GTK_EVENT_SEQUENCE_DENIED); }
If both gestures are in the same group, just set the state on the gesture emitting the event, the sequence will be already be initialized to the group's global state when the second gesture processes the event.
Since: 3.14
setState
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> EventSequenceState |
|
-> m Bool | Returns: |
Sets the state of all sequences that gesture
is currently
interacting with. See gestureSetSequenceState
for more details on sequence states.
Since: 3.14
setWindow
Sets a specific window to receive events about, so gesture
will effectively handle only events targeting window
, or
a child of it. window
must pertain to eventControllerGetWidget
.
Since: 3.14
ungroup
:: (HasCallStack, MonadIO m, IsGesture a) | |
=> a |
|
-> m () |
Separates gesture
into an isolated group.
Since: 3.14
Properties
nPoints
The number of touch points that trigger recognition on this gesture,
Since: 3.14
constructGestureNPoints :: IsGesture o => Word32 -> IO (GValueConstruct o) Source #
Construct a GValueConstruct
with valid value for the “n-points
” property. This is rarely needed directly, but it is used by new
.
getGestureNPoints :: (MonadIO m, IsGesture o) => o -> m Word32 Source #
Get the value of the “n-points
” property.
When overloading is enabled, this is equivalent to
get
gesture #nPoints
window
If non-Nothing
, the gesture will only listen for events that happen on
this Window
, or a child of it.
Since: 3.14
clearGestureWindow :: (MonadIO m, IsGesture o) => o -> m () Source #
Set the value of the “window
” property to Nothing
.
When overloading is enabled, this is equivalent to
clear
#window
constructGestureWindow :: (IsGesture o, IsWindow a) => a -> IO (GValueConstruct o) Source #
Construct a GValueConstruct
with valid value for the “window
” property. This is rarely needed directly, but it is used by new
.
getGestureWindow :: (MonadIO m, IsGesture o) => o -> m (Maybe Window) Source #
Get the value of the “window
” property.
When overloading is enabled, this is equivalent to
get
gesture #window
setGestureWindow :: (MonadIO m, IsGesture o, IsWindow a) => o -> a -> m () Source #
Set the value of the “window
” property.
When overloading is enabled, this is equivalent to
set
gesture [ #window:=
value ]
Signals
begin
type C_GestureBeginCallback = Ptr () -> Ptr EventSequence -> Ptr () -> IO () Source #
Type for the callback on the (unwrapped) C side.
type GestureBeginCallback Source #
= EventSequence |
|
-> IO () |
This signal is emitted when the gesture is recognized. This means the
number of touch sequences matches Gesture
:n-points
, and the Gesture
::check
handler(s) returned TRUE
.
Note: These conditions may also happen when an extra touch (eg. a third touch
on a 2-touches gesture) is lifted, in that situation sequence
won't pertain
to the current set of active touches, so don't rely on this being true.
Since: 3.14
afterGestureBegin :: (IsGesture a, MonadIO m) => a -> GestureBeginCallback -> m SignalHandlerId Source #
Connect a signal handler for the “begin
” signal, to be run after the default handler.
When overloading is enabled, this is equivalent to
after
gesture #begin callback
genClosure_GestureBegin :: GestureBeginCallback -> IO Closure Source #
Wrap the callback into a Closure
.
mk_GestureBeginCallback :: C_GestureBeginCallback -> IO (FunPtr C_GestureBeginCallback) Source #
Generate a function pointer callable from C code, from a C_GestureBeginCallback
.
noGestureBeginCallback :: Maybe GestureBeginCallback Source #
A convenience synonym for
.Nothing
:: Maybe
GestureBeginCallback
onGestureBegin :: (IsGesture a, MonadIO m) => a -> GestureBeginCallback -> m SignalHandlerId Source #
Connect a signal handler for the “begin
” signal, to be run before the default handler.
When overloading is enabled, this is equivalent to
on
gesture #begin callback
wrap_GestureBeginCallback :: GestureBeginCallback -> C_GestureBeginCallback Source #
Wrap a GestureBeginCallback
into a C_GestureBeginCallback
.
cancel
type C_GestureCancelCallback = Ptr () -> Ptr EventSequence -> Ptr () -> IO () Source #
Type for the callback on the (unwrapped) C side.
type GestureCancelCallback Source #
= EventSequence |
|
-> IO () |
This signal is emitted whenever a sequence is cancelled. This usually
happens on active touches when eventControllerReset
is called
on gesture
(manually, due to grabs...), or the individual sequence
was claimed by parent widgets' controllers (see gestureSetSequenceState
).
gesture
must forget everything about sequence
as a reaction to this signal.
Since: 3.14
afterGestureCancel :: (IsGesture a, MonadIO m) => a -> GestureCancelCallback -> m SignalHandlerId Source #
Connect a signal handler for the “cancel
” signal, to be run after the default handler.
When overloading is enabled, this is equivalent to
after
gesture #cancel callback
genClosure_GestureCancel :: GestureCancelCallback -> IO Closure Source #
Wrap the callback into a Closure
.
mk_GestureCancelCallback :: C_GestureCancelCallback -> IO (FunPtr C_GestureCancelCallback) Source #
Generate a function pointer callable from C code, from a C_GestureCancelCallback
.
noGestureCancelCallback :: Maybe GestureCancelCallback Source #
A convenience synonym for
.Nothing
:: Maybe
GestureCancelCallback
onGestureCancel :: (IsGesture a, MonadIO m) => a -> GestureCancelCallback -> m SignalHandlerId Source #
Connect a signal handler for the “cancel
” signal, to be run before the default handler.
When overloading is enabled, this is equivalent to
on
gesture #cancel callback
wrap_GestureCancelCallback :: GestureCancelCallback -> C_GestureCancelCallback Source #
Wrap a GestureCancelCallback
into a C_GestureCancelCallback
.
end
type C_GestureEndCallback = Ptr () -> Ptr EventSequence -> Ptr () -> IO () Source #
Type for the callback on the (unwrapped) C side.
type GestureEndCallback Source #
= EventSequence |
|
-> IO () |
This signal is emitted when gesture
either stopped recognizing the event
sequences as something to be handled (the Gesture
::check
handler returned
False
), or the number of touch sequences became higher or lower than
Gesture
:n-points
.
Note: sequence
might not pertain to the group of sequences that were
previously triggering recognition on gesture
(ie. a just pressed touch
sequence that exceeds Gesture
:n-points
). This situation may be detected
by checking through gestureHandlesSequence
.
Since: 3.14
afterGestureEnd :: (IsGesture a, MonadIO m) => a -> GestureEndCallback -> m SignalHandlerId Source #
Connect a signal handler for the “end
” signal, to be run after the default handler.
When overloading is enabled, this is equivalent to
after
gesture #end callback
genClosure_GestureEnd :: GestureEndCallback -> IO Closure Source #
Wrap the callback into a Closure
.
mk_GestureEndCallback :: C_GestureEndCallback -> IO (FunPtr C_GestureEndCallback) Source #
Generate a function pointer callable from C code, from a C_GestureEndCallback
.
noGestureEndCallback :: Maybe GestureEndCallback Source #
A convenience synonym for
.Nothing
:: Maybe
GestureEndCallback
onGestureEnd :: (IsGesture a, MonadIO m) => a -> GestureEndCallback -> m SignalHandlerId Source #
Connect a signal handler for the “end
” signal, to be run before the default handler.
When overloading is enabled, this is equivalent to
on
gesture #end callback
wrap_GestureEndCallback :: GestureEndCallback -> C_GestureEndCallback Source #
Wrap a GestureEndCallback
into a C_GestureEndCallback
.
sequenceStateChanged
type C_GestureSequenceStateChangedCallback = Ptr () -> Ptr EventSequence -> CUInt -> Ptr () -> IO () Source #
Type for the callback on the (unwrapped) C side.
type GestureSequenceStateChangedCallback Source #
= EventSequence |
|
-> EventSequenceState |
|
-> IO () |
This signal is emitted whenever a sequence state changes. See
gestureSetSequenceState
to know more about the expectable
sequence lifetimes.
Since: 3.14
afterGestureSequenceStateChanged :: (IsGesture a, MonadIO m) => a -> GestureSequenceStateChangedCallback -> m SignalHandlerId Source #
Connect a signal handler for the “sequence-state-changed
” signal, to be run after the default handler.
When overloading is enabled, this is equivalent to
after
gesture #sequenceStateChanged callback
genClosure_GestureSequenceStateChanged :: GestureSequenceStateChangedCallback -> IO Closure Source #
Wrap the callback into a Closure
.
mk_GestureSequenceStateChangedCallback :: C_GestureSequenceStateChangedCallback -> IO (FunPtr C_GestureSequenceStateChangedCallback) Source #
Generate a function pointer callable from C code, from a C_GestureSequenceStateChangedCallback
.
noGestureSequenceStateChangedCallback :: Maybe GestureSequenceStateChangedCallback Source #
A convenience synonym for
.Nothing
:: Maybe
GestureSequenceStateChangedCallback
onGestureSequenceStateChanged :: (IsGesture a, MonadIO m) => a -> GestureSequenceStateChangedCallback -> m SignalHandlerId Source #
Connect a signal handler for the “sequence-state-changed
” signal, to be run before the default handler.
When overloading is enabled, this is equivalent to
on
gesture #sequenceStateChanged callback
wrap_GestureSequenceStateChangedCallback :: GestureSequenceStateChangedCallback -> C_GestureSequenceStateChangedCallback Source #
update
type C_GestureUpdateCallback = Ptr () -> Ptr EventSequence -> Ptr () -> IO () Source #
Type for the callback on the (unwrapped) C side.
type GestureUpdateCallback Source #
= EventSequence |
|
-> IO () |
This signal is emitted whenever an event is handled while the gesture is
recognized. sequence
is guaranteed to pertain to the set of active touches.
Since: 3.14
afterGestureUpdate :: (IsGesture a, MonadIO m) => a -> GestureUpdateCallback -> m SignalHandlerId Source #
Connect a signal handler for the “update
” signal, to be run after the default handler.
When overloading is enabled, this is equivalent to
after
gesture #update callback
genClosure_GestureUpdate :: GestureUpdateCallback -> IO Closure Source #
Wrap the callback into a Closure
.
mk_GestureUpdateCallback :: C_GestureUpdateCallback -> IO (FunPtr C_GestureUpdateCallback) Source #
Generate a function pointer callable from C code, from a C_GestureUpdateCallback
.
noGestureUpdateCallback :: Maybe GestureUpdateCallback Source #
A convenience synonym for
.Nothing
:: Maybe
GestureUpdateCallback
onGestureUpdate :: (IsGesture a, MonadIO m) => a -> GestureUpdateCallback -> m SignalHandlerId Source #
Connect a signal handler for the “update
” signal, to be run before the default handler.
When overloading is enabled, this is equivalent to
on
gesture #update callback