GI.Gtk.Objects.GestureZoom

GestureZoom is a Gesture implementation able to recognize pinch/zoom gestures, whenever the distance between both tracked sequences changes, the scaleChanged signal is emitted to report the scale factor.

Exported types

newtype GestureZoom

Memory-managed wrapper type.

Constructors

GestureZoom (ManagedPtr GestureZoom)

Instances

Eq GestureZoom

Defined in GI.Gtk.Objects.GestureZoom

Methods

(==) :: GestureZoom -> GestureZoom -> Bool

(/=) :: GestureZoom -> GestureZoom -> Bool

IsGValue GestureZoom

Convert GestureZoom to and from GValue with toGValue and fromGValue.

Defined in GI.Gtk.Objects.GestureZoom

Methods

toGValue :: GestureZoom -> IO GValue

fromGValue :: GValue -> IO GestureZoom

GObject GestureZoom

Defined in GI.Gtk.Objects.GestureZoom

Methods

gobjectType :: IO GType

HasParentTypes GestureZoom

Defined in GI.Gtk.Objects.GestureZoom

type ParentTypes GestureZoom

Defined in GI.Gtk.Objects.GestureZoom

type ParentTypes GestureZoom = '[Gesture, EventController, Object]

class (GObject o, IsDescendantOf GestureZoom o) => IsGestureZoom o

Type class for types which can be safely cast to GestureZoom, for instance with toGestureZoom.

Instances

(GObject o, IsDescendantOf GestureZoom o) => IsGestureZoom o

Defined in GI.Gtk.Objects.GestureZoom

toGestureZoom :: (MonadIO m, IsGestureZoom o) => o -> m GestureZoom

Cast to GestureZoom, for types for which this is known to be safe. For general casts, use castTo.

Methods

Overloaded methods

getScaleDelta

gestureZoomGetScaleDelta

Arguments

:: (HasCallStack, MonadIO m, IsGestureZoom a)

=> a

gesture: a GestureZoom

-> m Double

Returns: the scale delta

If gesture is active, this function returns the zooming difference since the gesture was recognized (hence the starting point is considered 1:1). If gesture is not active, 1 is returned.

Since: 3.14

new

gestureZoomNew

Arguments

:: (HasCallStack, MonadIO m, IsWidget a)

=> a

widget: a Widget

-> m GestureZoom

Returns: a newly created GestureZoom

Returns a newly created Gesture that recognizes zoom in/out gestures (usually known as pinch/zoom).

Since: 3.14

Signals

scaleChanged

type C_GestureZoomScaleChangedCallback = Ptr () -> CDouble -> Ptr () -> IO ()

Type for the callback on the (unwrapped) C side.

type GestureZoomScaleChangedCallback

Arguments

 = Double

scale: Scale delta, taking the initial state as 1:1

-> IO ()

This signal is emitted whenever the distance between both tracked sequences changes.

Since: 3.14

afterGestureZoomScaleChanged :: (IsGestureZoom a, MonadIO m) => a -> GestureZoomScaleChangedCallback -> m SignalHandlerId

Connect a signal handler for the scaleChanged signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after gestureZoom #scaleChanged callback

genClosure_GestureZoomScaleChanged :: MonadIO m => GestureZoomScaleChangedCallback -> m (GClosure C_GestureZoomScaleChangedCallback)

Wrap the callback into a GClosure.

mk_GestureZoomScaleChangedCallback :: C_GestureZoomScaleChangedCallback -> IO (FunPtr C_GestureZoomScaleChangedCallback)

Generate a function pointer callable from C code, from a C_GestureZoomScaleChangedCallback.

noGestureZoomScaleChangedCallback :: Maybe GestureZoomScaleChangedCallback

A convenience synonym for Nothing :: Maybe GestureZoomScaleChangedCallback.

onGestureZoomScaleChanged :: (IsGestureZoom a, MonadIO m) => a -> GestureZoomScaleChangedCallback -> m SignalHandlerId

Connect a signal handler for the scaleChanged signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on gestureZoom #scaleChanged callback

wrap_GestureZoomScaleChangedCallback :: GestureZoomScaleChangedCallback -> C_GestureZoomScaleChangedCallback

Wrap a GestureZoomScaleChangedCallback into a C_GestureZoomScaleChangedCallback.