QML animations visible property changes

Question

I want an animation to be painted when an element becomes visible (is should appear smoothly, not the whole at all)

I tried this

states: State
{
    name         


        

Answer 1

I had to modify Uga Buga's answer slightly to make it work, here's what I got:

Rectangle {
    id: myRect
    property bool stateVisible: true
            ...
    states: [
        State { when: myRect.stateVisible; 
                PropertyChanges {   target: myRect; opacity: 1.0    }},
        State { when: !myRect.stateVisible;
                PropertyChanges {   target: myRect; opacity: 0.0    }}
    ]
    transitions: [ Transition { NumberAnimation { property: "opacity"; duration: 500}} ]
}

Please note that stateVisible is referenced through item id, it doesn't work without it on my system. Maybe some change in API caused this.

I also added square bracket in transitions field as an array is required there (although QML syntax seems to allow spelling without brackets)