A size type has width and height attributes.
For example, to read the Image::sourceSize size property:
Column { Image { id: image; source: "logo.png" } Text { text: image.sourceSize.width + "," + image.sourceSize.height } }
To create a size value, specify it as a "width x height" string:
LayoutItem { preferredSize: "150x50" }
Or use the Qt.size() function:
LayoutItem { preferredSize: Qt.size(150, 50) }
See also QML Basic Types.