PropertyAnimation in signal handler

[Mark81]

According to the docs the PropertyAnimation can be used in signal handlers:

MouseArea {
    anchors.fill: theObject
    onClicked: PropertyAnimation { target: theObject; property: "opacity"; to: 0 }
}

But why is not possible to use the braces around?

MouseArea {
    anchors.fill: theObject
    onClicked: {
        PropertyAnimation { target: theObject; property: "opacity"; to: 0 }
    }
}

This leads to the following error:

Expected token ,

[GrecKo]

Because when using braces you are now in a javascript scope, and you can't create QML objects declaratively like that in js.

What are you trying to do?

My 2 cents: I wasn't even aware that you could do that and my first reaction was disbelief. This QML feature of assigning an animation to a signal handler seems like a bad idea and isn't really intuitive.

[Mark81]

@GrecKo I was trying to find a way to execute an animation without declaring it separately. In "meta-code":

onSignalTrigger: {
    timer.stop()
    doSomething()
    doSomethingElse()
    // animate property
    PropertyAnimation { target: theObject; property: "opacity"; to: 0 }
}

The long way is:

PropertyAnimation { id: myAnim; target: theObject; property: "opacity"; to: 0 }

onSignalTrigger: {
    timer.stop()
    doSomething()
    doSomethingElse()
    // animate property
    myAnim.start()
}

I find the first syntax is more readable