Struct gtk::Gesture

source · [−]

#[repr(transparent)]
pub struct Gesture { /* private fields */ }

Expand description

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 None gdk::EventSequence value for these).

The number of touches that a Gesture need to be recognized is controlled by the property::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 signal::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:

signal::Gesture::begin when the gesture is recognized.
A number of signal::Gesture::update, whenever an input event is processed.
signal::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 EventControllerExt::set_propagation_phase(), or feed those manually through EventControllerExt::handle_event().

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 signal::Widget::button-press-event, signal::Widget::button-release-event, signal::Widget::touch-event, etc signals. Gestures with the PropagationPhase::Target phase are fed events from the default signal::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.

States of a sequence # {`touch`-sequence-states}

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 GestureExt::group_with(), grouped gestures synchronize the state of sequences, so calling GestureExt::set_sequence_state() on one will effectively propagate the state throughout the group.

By default, all sequences start out in the EventSequenceState::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 EventSequenceState::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 EventSequenceState::Claimed state, the gesture group will grab all interaction on the sequence, by:

Setting the same sequence to EventSequenceState::Denied on every other gesture group within the widget, and every gesture on parent widgets in the propagation chain.
calling signal::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 EventSequenceState::Claimed on GDK_TOUCH_BEGIN/GDK_BUTTON_PRESS (so those events are captured before reaching the event widget, this implies PropagationPhase::Capture), one similar event will emulated if the sequence changes to EventSequenceState::Denied. This way event coherence is preserved before event propagation is unstopped again.

Sequence states can’t be changed freely, see GestureExt::set_sequence_state() to know about the possible lifetimes of a gdk::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 gdk::EventMask::TOUCHPAD_GESTURE_MASK on their GdkWindows
If the gesture has PropagationPhase::None, ensuring events of type GDK_TOUCHPAD_SWIPE and GDK_TOUCHPAD_PINCH are handled by the Gesture

This is an Abstract Base Class, you cannot instantiate it.

Struct gtk::Gesture

Implementations

impl Gesture

pub const NONE: Option<&'static Gesture> = None

Trait Implementations

impl Clone for Gesture

fn clone(&self) -> Self

fn clone_from(&mut self, source: &Self)

impl Debug for Gesture

fn fmt(&self, f: &mut Formatter<'_>) -> Result

impl Display for Gesture

fn fmt(&self, f: &mut Formatter<'_>) -> Result

impl Hash for Gesture

fn hash<H>(&self, state: &mut H) where H: Hasher,

fn hash_slice<H>(data: &[Self], state: &mut H) where H: Hasher,

impl Ord for Gesture

fn cmp(&self, other: &Self) -> Ordering

fn max(self, other: Self) -> Self

fn min(self, other: Self) -> Self

fn clamp(self, min: Self, max: Self) -> Self

impl ParentClassIs for Gesture

type Parent = EventController

impl<OT: ObjectType> PartialEq<OT> for Gesture

fn eq(&self, other: &OT) -> bool

fn ne(&self, other: &Rhs) -> bool

impl<OT: ObjectType> PartialOrd<OT> for Gesture

fn partial_cmp(&self, other: &OT) -> Option<Ordering>

fn lt(&self, other: &Rhs) -> bool

fn le(&self, other: &Rhs) -> bool

fn gt(&self, other: &Rhs) -> bool

fn ge(&self, other: &Rhs) -> bool

impl StaticType for Gesture

fn static_type() -> Type

impl Eq for Gesture

impl IsA<EventController> for Gesture

impl IsA<Gesture> for GestureDrag

impl IsA<Gesture> for GestureLongPress

impl IsA<Gesture> for GestureMultiPress

impl IsA<Gesture> for GesturePan

impl IsA<Gesture> for GestureRotate

impl IsA<Gesture> for GestureSingle

impl IsA<Gesture> for GestureStylus

impl IsA<Gesture> for GestureSwipe

impl IsA<Gesture> for GestureZoom

Auto Trait Implementations

impl RefUnwindSafe for Gesture

impl !Send for Gesture

impl !Sync for Gesture

impl Unpin for Gesture

impl UnwindSafe for Gesture

Blanket Implementations

impl<T> Any for T where T: 'static + ?Sized,

fn type_id(&self) -> TypeId

impl<T> Borrow<T> for T where T: ?Sized,

fn borrow(&self) -> &T

impl<T> BorrowMut<T> for T where T: ?Sized,

fn borrow_mut(&mut self) -> &mut T

impl<T> Cast for T where T: ObjectType,

fn upcast<T>(self) -> T where T: ObjectType, Self: IsA<T>,

fn upcast_ref<T>(&self) -> &T where T: ObjectType, Self: IsA<T>,

fn downcast<T>(self) -> Result<T, Self> where T: ObjectType, Self: CanDowncast<T>,

fn downcast_ref<T>(&self) -> Option<&T> where T: ObjectType, Self: CanDowncast<T>,

fn dynamic_cast<T>(self) -> Result<T, Self> where T: ObjectType,

fn dynamic_cast_ref<T>(&self) -> Option<&T> where T: ObjectType,

unsafe fn unsafe_cast<T>(self) -> T where T: ObjectType,

unsafe fn unsafe_cast_ref<T>(&self) -> &T where T: ObjectType,

impl<T> From<T> for T

fn from(t: T) -> T

impl<T, U> Into<U> for T where U: From<T>,

fn into(self) -> U

impl<U> IsSubclassableExt for U where U: IsClass + ParentClassIs,

fn parent_class_init<T>(class: &mut Class<U>) where T: ObjectSubclass, <U as ParentClassIs>::Parent: IsSubclassable<T>,

fn parent_instance_init<T>(instance: &mut InitializingObject<T>) where T: ObjectSubclass, <U as ParentClassIs>::Parent: IsSubclassable<T>,

impl<T> ObjectExt for T where T: ObjectType,

fn is<U>(&self) -> bool where U: StaticType,

fn type_(&self) -> Type

fn object_class(&self) -> &Class<Object>

fn class(&self) -> &Class<T> where T: IsClass,

fn class_of<U>(&self) -> Option<&Class<U>> where U: IsClass,

fn interface<U>(&self) -> Option<InterfaceRef<'_, U>> where U: IsInterface,

fn hash<H>(&self, state: &mut H) where
H: Hasher,

fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,

impl<T> Any for T where
T: 'static + ?Sized,

impl<T> Borrow<T> for T where
T: ?Sized,

impl<T> BorrowMut<T> for T where
T: ?Sized,

impl<T> Cast for T where
T: ObjectType,

fn upcast<T>(self) -> T where
T: ObjectType,
Self: IsA<T>,

fn upcast_ref<T>(&self) -> &T where
T: ObjectType,
Self: IsA<T>,

fn downcast<T>(self) -> Result<T, Self> where
T: ObjectType,
Self: CanDowncast<T>,

fn downcast_ref<T>(&self) -> Option<&T> where
T: ObjectType,
Self: CanDowncast<T>,

fn dynamic_cast<T>(self) -> Result<T, Self> where
T: ObjectType,

fn dynamic_cast_ref<T>(&self) -> Option<&T> where
T: ObjectType,

unsafe fn unsafe_cast<T>(self) -> T where
T: ObjectType,

unsafe fn unsafe_cast_ref<T>(&self) -> &T where
T: ObjectType,

impl<T, U> Into<U> for T where
U: From<T>,

impl<U> IsSubclassableExt for U where
U: IsClass + ParentClassIs,

fn parent_class_init<T>(class: &mut Class<U>) where
T: ObjectSubclass,
<U as ParentClassIs>::Parent: IsSubclassable<T>,

fn parent_instance_init<T>(instance: &mut InitializingObject<T>) where
T: ObjectSubclass,
<U as ParentClassIs>::Parent: IsSubclassable<T>,

impl<T> ObjectExt for T where
T: ObjectType,

fn is<U>(&self) -> bool where
U: StaticType,

fn class(&self) -> &Class<T> where
T: IsClass,

fn class_of<U>(&self) -> Option<&Class<U>> where
U: IsClass,

fn interface<U>(&self) -> Option<InterfaceRef<'_, U>> where
U: IsInterface,

fn try_set_property<V>(
&self,
property_name: &str,
value: V
) -> Result<(), BoolError> where
V: ToValue,

fn set_property<V>(&self, property_name: &str, value: V) where
V: ToValue,

fn try_set_property_from_value(
&self,
property_name: &str,
value: &Value
) -> Result<(), BoolError>

fn try_set_properties(
&self,
property_values: &[(&str, &dyn ToValue )]
) -> Result<(), BoolError>

fn set_properties(&self, property_values: &[(&str, &dyn ToValue )])

fn try_set_properties_from_value(
&self,
property_values: &[(&str, Value )]
) -> Result<(), BoolError>

fn set_properties_from_value(&self, property_values: &[(&str, Value )])

fn try_property<V>(&self, property_name: &str) -> Result<V, BoolError> where
V: 'static + for<'b> FromValue<'b>,

fn property<V>(&self, property_name: &str) -> V where
V: 'static + for<'b> FromValue<'b>,

unsafe fn set_qdata<QD>(&self, key: Quark, value: QD) where
QD: 'static,

unsafe fn qdata<QD>(&self, key: Quark) -> Option<NonNull<QD>> where
QD: 'static,

unsafe fn steal_qdata<QD>(&self, key: Quark) -> Option<QD> where
QD: 'static,

unsafe fn set_data<QD>(&self, key: &str, value: QD) where
QD: 'static,

unsafe fn data<QD>(&self, key: &str) -> Option<NonNull<QD>> where
QD: 'static,

unsafe fn steal_data<QD>(&self, key: &str) -> Option<QD> where
QD: 'static,

fn try_connect<F>(
&self,
signal_name: &str,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: 'static + Fn(&[Value ]) -> Option<Value> + Send + Sync,

fn connect<F>(
&self,
signal_name: &str,
after: bool,
callback: F
) -> SignalHandlerId where
F: 'static + Fn(&[Value ]) -> Option<Value> + Send + Sync,

fn try_connect_id<F>(
&self,
signal_id: SignalId,
details: Option<Quark>,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: 'static + Fn(&[Value ]) -> Option<Value> + Send + Sync,

fn connect_id<F>(
&self,
signal_id: SignalId,
details: Option<Quark>,
after: bool,
callback: F
) -> SignalHandlerId where
F: 'static + Fn(&[Value ]) -> Option<Value> + Send + Sync,

fn try_connect_local<F>(
&self,
signal_name: &str,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: 'static + Fn(&[Value ]) -> Option<Value>,

fn connect_local<F>(
&self,
signal_name: &str,
after: bool,
callback: F
) -> SignalHandlerId where
F: 'static + Fn(&[Value ]) -> Option<Value>,

fn try_connect_local_id<F>(
&self,
signal_id: SignalId,
details: Option<Quark>,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: 'static + Fn(&[Value ]) -> Option<Value>,

fn connect_local_id<F>(
&self,
signal_id: SignalId,
details: Option<Quark>,
after: bool,
callback: F
) -> SignalHandlerId where
F: 'static + Fn(&[Value ]) -> Option<Value>,

unsafe fn try_connect_unsafe<F>(
&self,
signal_name: &str,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value ]) -> Option<Value>,

unsafe fn connect_unsafe<F>(
&self,
signal_name: &str,
after: bool,
callback: F
) -> SignalHandlerId where
F: Fn(&[Value ]) -> Option<Value>,

unsafe fn try_connect_unsafe_id<F>(
&self,
signal_id: SignalId,
details: Option<Quark>,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value ]) -> Option<Value>,

fn try_connect_closure(
&self,
signal_name: &str,
after: bool,
closure: RustClosure
) -> Result<SignalHandlerId, BoolError>

fn connect_closure(
&self,
signal_name: &str,
after: bool,
closure: RustClosure
) -> SignalHandlerId

fn try_connect_closure_id(
&self,
signal_id: SignalId,
details: Option<Quark>,
after: bool,
closure: RustClosure
) -> Result<SignalHandlerId, BoolError>

fn connect_closure_id(
&self,
signal_id: SignalId,
details: Option<Quark>,
after: bool,
closure: RustClosure
) -> SignalHandlerId

unsafe fn connect_unsafe_id<F>(
&self,
signal_id: SignalId,
details: Option<Quark>,
after: bool,
callback: F
) -> SignalHandlerId where
F: Fn(&[Value ]) -> Option<Value>,

fn try_emit<R>(
&self,
signal_id: SignalId,
args: &[&dyn ToValue ]
) -> Result<R, BoolError> where
R: TryFromClosureReturnValue,

fn emit<R>(&self, signal_id: SignalId, args: &[&dyn ToValue ]) -> R where
R: TryFromClosureReturnValue,

fn try_emit_with_values(
&self,
signal_id: SignalId,
args: &[Value ]
) -> Result<Option<Value>, BoolError>

fn emit_with_values(&self, signal_id: SignalId, args: &[Value ]) -> Option<Value>

fn try_emit_by_name<R>(
&self,
signal_name: &str,
args: &[&dyn ToValue ]
) -> Result<R, BoolError> where
R: TryFromClosureReturnValue,

fn emit_by_name<R>(&self, signal_name: &str, args: &[&dyn ToValue ]) -> R where
R: TryFromClosureReturnValue,

fn try_emit_by_name_with_values(
&self,
signal_name: &str,
args: &[Value ]
) -> Result<Option<Value>, BoolError>

fn emit_by_name_with_values(
&self,
signal_name: &str,
args: &[Value ]
) -> Option<Value>

fn try_emit_with_details<R>(
&self,
signal_id: SignalId,
details: Quark,
args: &[&dyn ToValue ]
) -> Result<R, BoolError> where
R: TryFromClosureReturnValue,

fn emit_with_details<R>(
&self,
signal_id: SignalId,
details: Quark,
args: &[&dyn ToValue ]
) -> R where
R: TryFromClosureReturnValue,

fn try_emit_with_details_and_values(
&self,
signal_id: SignalId,
details: Quark,
args: &[Value ]
) -> Result<Option<Value>, BoolError>

fn emit_with_details_and_values(
&self,
signal_id: SignalId,
details: Quark,
args: &[Value ]
) -> Option<Value>

fn connect_notify<F>(&self, name: Option<&str>, f: F) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec) + Send + Sync,

fn connect_notify_local<F>(&self, name: Option<&str>, f: F) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec),