transition/effects.go
Functions
func FadeIn
func FadeIn() Effect {
return Effect{
OpacityStart: 0,
OpacityEnd: 1,
ScaleStart: noScale,
}
}
func FadeOut
FadeOut returns an effect that fades opacity from 1 to 0.
func FadeOut() Effect {
return Effect{
OpacityStart: 1,
OpacityEnd: 0,
ScaleStart: noScale,
}
}
func IsNone
IsNone reports whether the effect performs no animation.
func (e Effect) IsNone() bool {
hasOpacity := e.OpacityStart >= 0
hasTranslate := e.TranslateXFraction != 0 || e.TranslateYFraction != 0
hasScale := e.ScaleStart >= 0
return !hasOpacity && !hasTranslate && !hasScale
}
func None
None returns an effect that performs no animation (instant transition).
func None() Effect {
return Effect{
OpacityStart: noOpacity,
ScaleStart: noScale,
}
}
func ScaleIn
ScaleIn returns an effect that scales from 0.8 to 1.0 with a fade in.
func ScaleIn() Effect {
return Effect{
OpacityStart: 0,
OpacityEnd: 1,
ScaleStart: 0.8,
ScaleEnd: 1.0,
}
}
func ScaleOut
ScaleOut returns an effect that scales from 1.0 to 0.8 with a fade out.
func ScaleOut() Effect {
return Effect{
OpacityStart: 1,
OpacityEnd: 0,
ScaleStart: 1.0,
ScaleEnd: 0.8,
}
}
func SlideIn
SlideIn returns a slide-in effect from the given direction.
The widget slides from off-screen (one full dimension away) to its
final position. Only From* directions are meaningful for enter effects;
To* directions are treated as their From* equivalents.
func SlideIn(dir Direction) Effect {
e := Effect{
OpacityStart: noOpacity,
ScaleStart: noScale,
}
switch dir {
case FromTop, ToTop:
e.TranslateYFraction = -1.0
case FromBottom, ToBottom:
e.TranslateYFraction = 1.0
case FromLeft, ToLeft:
e.TranslateXFraction = -1.0
case FromRight, ToRight:
e.TranslateXFraction = 1.0
}
return e
}
func SlideOut
SlideOut returns a slide-out effect toward the given direction.
The widget slides from its current position to off-screen. Only To*
directions are meaningful for exit effects; From* directions are
treated as their To* equivalents.
func SlideOut(dir Direction) Effect {
e := Effect{
OpacityStart: noOpacity,
ScaleStart: noScale,
}
switch dir {
case ToTop, FromTop:
e.TranslateYFraction = -1.0
case ToBottom, FromBottom:
e.TranslateYFraction = 1.0
case ToLeft, FromLeft:
e.TranslateXFraction = -1.0
case ToRight, FromRight:
e.TranslateXFraction = 1.0
}
return e
}
Structs
type Effect struct
Effect describes the visual transformation applied during a transition.
Each field pair (Start/End) defines the range of animation for that
property. A negative Start value means the property is not animated.
Effect is a value type; create instances via the provided constructors.
type Effect struct {
// OpacityStart is the starting opacity. Negative means opacity is not animated.
OpacityStart float64
// OpacityEnd is the ending opacity.
OpacityEnd float64
// TranslateXFraction is the starting X offset as a fraction of widget width.
// For example, -1.0 means start one full width to the left.
TranslateXFraction float64
// TranslateYFraction is the starting Y offset as a fraction of widget height.
TranslateYFraction float64
// ScaleStart is the starting scale factor. Negative means scale is not animated.
ScaleStart float64
// ScaleEnd is the ending scale factor.
ScaleEnd float64
}
FadeIn returns an effect that fades opacity from 0 to 1.