[Qt-qml] Parenting with Flickable

[gabriel.dietrich-de at nokia.com]

Hi all,

I’m currently implementing a position indicator (kind of scrollbar) for the Qt Components project. My first shot, adding it to a ListView as a child worked quite well. Basically, it looks like this:

ListView {
    model: ...
    delegate: ...
    
    PositionIndicator { }    <---- Yes, its body is empty
}

Inside the PositionIndicator component I’m setting an alias property as the parent of the Item, and using its “visibleArea.*” properties. So far, so good.

Then I tried with Flickable, like this:

Flickable {
    contentWidth: ...
    contentHeight: ...
    
    Rectangle { ... }

    PositionIndicator { }
}

and I get an error about “visibleArea” not being defined. So I decided to set the PositionIndicator as a sibling of the Flickable with a property referencing it:

Flickable {
    id: rectFLick
    contentWidth: ...
    contentHeight: ...
    
    Rectangle { ... }
}

PositionIndicator {
    flickable: rectFLick
}

and it works again. Now the questions are,

1. What makes the difference between the parenting in ListView and Flickable, and why?

2. Which syntax should I “prefer” between both? (Even though the first syntax doesn’t work with Flickable, we may end up creating a list view and a flickable components for Qt Components, hence the question).

Thanks in advance.

Best regards,

Gabriel de Dietrich
Software Engineer
http://qt.nokia.com