QtQuick Behavior

Defines a default animation for a property change

Import Statement: import QtQuick 2.4


Detailed Description

A Behavior defines the default animation to be applied whenever a particular property value changes.

For example, the following Behavior defines a NumberAnimation to be run whenever the Rectangle’s width value changes. When the MouseArea is clicked, the width is changed, triggering the behavior’s animation:

import QtQuick 2.0
Rectangle {
    id: rect
    width: 100; height: 100
    color: "red"
    Behavior on width {
        NumberAnimation { duration: 1000 }
    MouseArea {
        anchors.fill: parent
        onClicked: rect.width = 50

Note that a property cannot have more than one assigned Behavior. To provide multiple animations within a Behavior, use ParallelAnimation or SequentialAnimation.

If a state change has a Transition that matches the same property as a Behavior, the Transition animation overrides the Behavior for that state change. For general advice on using Behaviors to animate state changes, see Using Qt Quick Behaviors with States .

See also Animation and Transitions in Qt Quick , Behavior example , and Qt QML.

Property Documentation

[default] animation : Animation

This property holds the animation to run when the behavior is triggered.

enabled : bool

This property holds whether the behavior will be triggered when the tracked property changes value.

By default a Behavior is enabled.