State(状态)组件是一组来自默认配置的批处理更改。所有项都有一个默认状态，该状态定义对象和属性值的默认配置。可以通过将State项添加到states属性来定义新的状态，以允许项在不同的配置之间切换。

State组件的基本用法如下：

Window {
    id: win
    width: 640
    height: 480
    visible: true
    title: qsTr("Hello World")

    Rectangle {
        id: rect
        anchors.fill: parent
        color: "steelblue"

        state: "initial"

        MouseArea {
            id: ma
            anchors.fill: parent
            hoverEnabled: true
            onClicked: {
                rect.state === 'clicked'? rect.state="":rect.state='clicked'
            }
            onEntered: {
                rect.state = "enter"
            }
            onExited: {
                rect.state = 'initial'
            }
        }

        states: [
            State {
                name: "initial"
                PropertyChanges {
                    target: rect
                    color: "steelblue"
                }
            },
            State {
                name: "clicked"
                PropertyChanges {
                    target: rect
                    color: "re"
                }
            },
            State {
                name: "enter"
                PropertyChanges {
                    target: rect
                    color: "green"
                }
            }
        ]
    }
}