[Qt-qml] Recommended way to parametrize QML items?

[Tomas Junnonen]

On 11/17/2010 02:20 PM, Kellomaki Pertti (Nokia-MS/Tampere) wrote:
> What is the recommended way to parametrize QML items? What I would like
> to achieve is something the following. The intent is to create a Foo
> where one part of the visual appearance is given by the bar property.
>
>      Foo { bar: Text { text: "bar text" } }
>      Foo { bar: Image { source: "bar-image.png" } }
>
> Looking at SpinBox.qml in the custom branch of qt-components [1], I see
> that one way to do this is to use a Loader element as a place holder
> inside the definition of Foo, and set it up in the onLoaded handler.
> This is clear enough, though it does look like a bit roundabout way of
> doing things.

First try to use a simple direct property binding:

main.qml:
import Qt 4.7

Rectangle {
     width: 200; height: 200

     Foo { bar: Text { text: "bar text" } }
     Foo { bar: Image { source: "bar-image.png" } }
}

Foo.qml:
import Qt 4.7

Rectangle {
     property Item bar

     children: bar
}

The parametrized bar item doesn't have to be a direct child of Foo 
either. Another way is to use the onBarChanged signal to Do What You 
Want(tm), for example if you need to anchor the item.

Regards,
Tomas