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PropertyAnimation QML Type
Animates changes in property values. More...
Import Statement: | import QtQuick |
Since: | Qt Quick Ultralite 1.0 |
Inherits: | |
Inherited By: |
Properties
- duration : int
- easing.type : enumeration
- from : variant
- properties : string
- property : string
- target : Object
- to : variant
Detailed Description
PropertyAnimation provides a way to animate changes to a property's value.
It can be used to define animations in a number of ways:
- In a Transition
For example, to animate any objects that have changed their
x
ory
properties as a result of a state change, using anInOutQuad
easing curve:Item { id: root Rectangle { id: rect width: 100; height: 100 color: "red" } states: State { name: "moved" PropertyChanges { target: rect; x: 50 } } transitions: Transition { PropertyAnimation { properties: "x,y"; easing.type: Easing.InOutQuad } } }
- In a Behavior
For example, to animate all changes to a rectangle's
x
property:Rectangle { width: 100; height: 100 color: "red" Behavior on x { PropertyAnimation {} } MouseArea { anchors.fill: parent; onClicked: parent.x = 50 } }
- As a property value source
For example, to repeatedly animate the rectangle's
x
property:Rectangle { width: 100; height: 100 color: "red" SequentialAnimation on x { loops: Animation.Infinite PropertyAnimation { to: 50 } PropertyAnimation { to: 0 } } }
- Standalone
For example, to animate
rect
'swidth
property over 500ms, from its current width to 30:Rectangle { id: theRect width: 100; height: 100 color: "red" // this is a standalone animation, it's not running by default PropertyAnimation { id: animation; target: theRect; property: "width"; to: 30; duration: 500 } MouseArea { anchors.fill: parent; onClicked: animation.running = true } }
Depending on how the animation is used, the set of properties normally used will be different. For more information see the individual property documentation, as well as the Animation and Transitions introduction.
Note that PropertyAnimation inherits the abstract Animation type. This includes additional properties and methods for controlling the animation.
See also Animation and Transitions.
Property Documentation
These properties are used as a set to determine which properties should be animated. The singular and plural forms are functionally identical, e.g.
NumberAnimation { target: theItem; property: "x"; to: 500; }
has the same meaning as
NumberAnimation { targets theItem; properties: "x"; to: 500; }
In many cases these properties do not need to be explicitly specified, as they can be inferred from the animation framework:
Value Source / Behavior | When an animation is used as a value source or in a Behavior, the default target and property name to be animated can both be inferred.Rectangle { id: theRect width: 100; height: 100 color: Qt.rgba(0,0,1) NumberAnimation on x { to: 500; loops: Animation.Infinite } //animate theRect's x property Behavior on y { NumberAnimation {} } //animate theRect's y property } |
Transition | When used in a transition, a property animation is assumed to match all targets but no properties. In practice, that means you need to specify at least the properties in order for the animation to do anything.Rectangle { id: theRect width: 100; height: 100 color: Qt.rgba(0,0,1) Item { id: uselessItem } states: State { name: "state1" PropertyChanges { target: theRect; x: 200; y: 200; z: 4 } PropertyChanges { target: uselessItem; x: 10; y: 10; z: 2 } } transitions: Transition { //animate both theRect's and uselessItem's x and y to their final values NumberAnimation { properties: "x,y" } //animate theRect's z to its final value NumberAnimation { target: theRect; property: "z" } } } |
Standalone | When an animation is used standalone, both the target and property need to be explicitly specified.Rectangle { id: theRect width: 100; height: 100 color: Qt.rgba(0,0,1) //need to explicitly specify target and property NumberAnimation { id: theAnim; target: theRect; property: "x"; to: 500 } MouseArea { anchors.fill: parent onClicked: theAnim.start() } } |
As seen in the above example, properties is specified as a comma-separated string of property names to animate.
See also Animation and Transitions.
duration : int |
This property holds the duration of the animation, in milliseconds.
The default value is 250.
easing.type : enumeration |
Specifies the easing curve used for the animation
To specify an easing curve you need to specify at least the type. For some curves you can also specify amplitude, period and/or overshoot (more details provided after the table). The default easing curve is Easing.Linear
.
PropertyAnimation { properties: "y"; easing.type: Easing.InOutSine; }
Available types are:
Easing.Linear | Easing curve for a linear (t) function: velocity is constant. | |
Easing.InQuad | Easing curve for a quadratic (t^2) function: accelerating from zero velocity. | |
Easing.OutQuad | Easing curve for a quadratic (t^2) function: decelerating to zero velocity. | |
Easing.InOutQuad | Easing curve for a quadratic (t^2) function: acceleration until halfway, then deceleration. | |
Easing.OutInQuad | Easing curve for a quadratic (t^2) function: deceleration until halfway, then acceleration. | |
Easing.InCubic | Easing curve for a cubic (t^3) function: accelerating from zero velocity. | |
Easing.OutCubic | Easing curve for a cubic (t^3) function: decelerating to zero velocity. | |
Easing.InOutCubic | Easing curve for a cubic (t^3) function: acceleration until halfway, then deceleration. | |
Easing.OutInCubic | Easing curve for a cubic (t^3) function: deceleration until halfway, then acceleration. | |
Easing.InQuart | Easing curve for a quartic (t^4) function: accelerating from zero velocity. | |
Easing.OutQuart | Easing curve for a quartic (t^4) function: decelerating to zero velocity. | |
Easing.InOutQuart | Easing curve for a quartic (t^4) function: acceleration until halfway, then deceleration. | |
Easing.OutInQuart | Easing curve for a quartic (t^4) function: deceleration until halfway, then acceleration. | |
Easing.InQuint | Easing curve for a quintic (t^5) function: accelerating from zero velocity. | |
Easing.OutQuint | Easing curve for a quintic (t^5) function: decelerating to zero velocity. | |
Easing.InOutQuint | Easing curve for a quintic (t^5) function: acceleration until halfway, then deceleration. | |
Easing.OutInQuint | Easing curve for a quintic (t^5) function: deceleration until halfway, then acceleration. | |
Easing.InSine | Easing curve for a sinusoidal (sin(t)) function: accelerating from zero velocity. | |
Easing.OutSine | Easing curve for a sinusoidal (sin(t)) function: decelerating to zero velocity. | |
Easing.InOutSine | Easing curve for a sinusoidal (sin(t)) function: acceleration until halfway, then deceleration. | |
Easing.OutInSine | Easing curve for a sinusoidal (sin(t)) function: deceleration until halfway, then acceleration. | |
Easing.InExpo | Easing curve for an exponential (2^t) function: accelerating from zero velocity. | |
Easing.OutExpo | Easing curve for an exponential (2^t) function: decelerating to zero velocity. | |
Easing.InOutExpo | Easing curve for an exponential (2^t) function: acceleration until halfway, then deceleration. | |
Easing.OutInExpo | Easing curve for an exponential (2^t) function: deceleration until halfway, then acceleration. | |
Easing.InCirc | Easing curve for a circular (sqrt(1-t^2)) function: accelerating from zero velocity. | |
Easing.OutCirc | Easing curve for a circular (sqrt(1-t^2)) function: decelerating to zero velocity. | |
Easing.InOutCirc | Easing curve for a circular (sqrt(1-t^2)) function: acceleration until halfway, then deceleration. | |
Easing.OutInCirc | Easing curve for a circular (sqrt(1-t^2)) function: deceleration until halfway, then acceleration. |
from : variant |
This property holds the starting value for the animation.
If the PropertyAnimation is defined within a Transition or Behavior, this value defaults to the value defined in the starting state of the Transition, or the current value of the property at the moment the Behavior is triggered.
See also Animation and Transitions.
to : variant |
This property holds the end value for the animation.
If the PropertyAnimation is defined within a Transition or Behavior, this value defaults to the value defined in the end state of the Transition, or the value of the property change that triggered the Behavior.
See also Animation and Transitions.
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