Gtk.GestureZoom
Description: Reference for Gtk.GestureZoom

### Class

# GtkGestureZoom

#### Description [src]

    final class Gtk.GestureZoom : Gtk.Gesture
    {
      /* No available fields */
    }

Recognizes 2-finger pinch/zoom gestures.

Whenever the distance between both tracked sequences changes, the `GtkGestureZoom::scale-changed` signal is emitted to report the scale factor.

#### Hierarchy

#### Ancestors

- GtkGesture
- GtkEventController
- GObject

#### Constructors

###### gtk_gesture_zoom_new

Returns a newly created `GtkGesture` that recognizes pinch/zoom gestures.

#### Instance methods

###### gtk_gesture_zoom_get_scale_delta

Gets the scale delta.

##### Methods inherited from GtkGesture (17)

###### gtk_gesture_get_bounding_box

If there are touch sequences being currently handled by `gesture`, returns `TRUE` and fills in `rect` with the bounding box containing all active touches.

###### gtk_gesture_get_bounding_box_center

If there are touch sequences being currently handled by `gesture`, returns `TRUE` and fills in `x` and `y` with the center of the bounding box containing all active touches.

###### gtk_gesture_get_device

Returns the logical `GdkDevice` that is currently operating on `gesture`.

###### gtk_gesture_get_group

Returns all gestures in the group of `gesture`.

###### gtk_gesture_get_last_event

Returns the last event that was processed for `sequence`.

###### gtk_gesture_get_last_updated_sequence

Returns the `GdkEventSequence` that was last updated on `gesture`.

###### gtk_gesture_get_point

If `sequence` is currently being interpreted by `gesture`, returns `TRUE` and fills in `x` and `y` with the last coordinates stored for that event sequence.

###### gtk_gesture_get_sequence_state

Returns the `sequence` state, as seen by `gesture`.

###### gtk_gesture_get_sequences

Returns the list of `GdkEventSequences` currently being interpreted by `gesture`.

###### gtk_gesture_group

Adds `gesture` to the same group than `group_gesture`.

###### gtk_gesture_handles_sequence

Returns `TRUE` if `gesture` is currently handling events corresponding to `sequence`.

###### gtk_gesture_is_active

Returns `TRUE` if the gesture is currently active.

###### gtk_gesture_is_grouped_with

Returns `TRUE` if both gestures pertain to the same group.

###### gtk_gesture_is_recognized

Returns `TRUE` if the gesture is currently recognized.

###### gtk_gesture_set_sequence_state

Sets the state of `sequence` in `gesture`.

deprecated: 4.10.

###### gtk_gesture_set_state

Sets the state of all sequences that `gesture` is currently interacting with.

###### gtk_gesture_ungroup

Separates `gesture` into an isolated group.

##### Methods inherited from GtkEventController (13)

###### gtk_event_controller_get_current_event

Returns the event that is currently being handled by the controller.

###### gtk_event_controller_get_current_event_device

Returns the device of the event that is currently being handled by the controller.

###### gtk_event_controller_get_current_event_state

Returns the modifier state of the event that is currently being handled by the controller.

###### gtk_event_controller_get_current_event_time

Returns the timestamp of the event that is currently being handled by the controller.

###### gtk_event_controller_get_name

Gets the name of `controller`.

###### gtk_event_controller_get_propagation_limit

Gets the propagation limit of the event controller.

###### gtk_event_controller_get_propagation_phase

Gets the propagation phase at which `controller` handles events.

###### gtk_event_controller_get_widget

Returns the `GtkWidget` this controller relates to.

###### gtk_event_controller_reset

Resets the `controller` to a clean state.

###### gtk_event_controller_set_name

Sets a name on the controller that can be used for debugging.

###### gtk_event_controller_set_propagation_limit

Sets the event propagation limit on the event controller.

###### gtk_event_controller_set_propagation_phase

Sets the propagation phase at which a controller handles events.

###### gtk_event_controller_set_static_name

Sets a name on the controller that can be used for debugging.

since: 4.8

##### Methods inherited from GObject (43)

Please see GObject for a full list of methods.

#### Properties

##### Properties inherited from GtkGesture (1)

###### Gtk.Gesture:n-points

The number of touch points that trigger recognition on this gesture.

##### Properties inherited from GtkEventController (4)

###### Gtk.EventController:name

The name for this controller, typically used for debugging purposes.

###### Gtk.EventController:propagation-limit

The limit for which events this controller will handle.

###### Gtk.EventController:propagation-phase

The propagation phase at which this controller will handle events.

###### Gtk.EventController:widget

The widget receiving the `GdkEvents` that the controller will handle.

#### Signals

###### Gtk.GestureZoom::scale-changed

Emitted whenever the distance between both tracked sequences changes.

##### Signals inherited from GtkGesture (5)

###### GtkGesture::begin

Emitted when the gesture is recognized.

###### GtkGesture::cancel

Emitted whenever a sequence is cancelled.

###### GtkGesture::end

Emitted when `gesture` either stopped recognizing the event sequences as something to be handled, or the number of touch sequences became higher or lower than `GtkGesture:n-points`.

###### GtkGesture::sequence-state-changed

Emitted whenever a sequence state changes.

###### GtkGesture::update

Emitted whenever an event is handled while the gesture is recognized.

##### Signals inherited from GObject (1)

###### GObject::notify

The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.

#### Class structure

    struct GtkGestureZoomClass {
      /* no available fields */
    }

No description available.