import QtQuick 2.12
import QtQuick.Window 2.12
import QtQuick.Controls 2.0

Window {
    width: 640
    height: 480
    visible: true
    title: qsTr("State.when bug")

    Item {
        id: item
        anchors.fill: parent

        property bool toggle

        Button {
            anchors.fill: parent
            onClicked: item.toggle = ! item.toggle
        }

        states: [
            State {
                name: "true"
                when: item.toggle
            },
            State {
                name: "false"
                when: ! item.toggle
            }
        ]

        onStateChanged: {
            console.log("state:", state, "toggle:", toggle)
        }
    }
}