This patch removes size policies and preferred sizes, and replaces them
with min-size and max-size for each widget.
Box layout now works in 3 passes:
1) Set all items (widgets/spacers) to their min-size
2) Distribute remaining space evenly, respecting max-size
3) Place widgets one after the other, adding spacing in between
I've also added convenience helpers for setting a fixed size (which is
the same as setting min-size and max-size to the same value.)
This significantly reduces the verbosity of widget layout and makes GML
a bit more pleasant to write, too. :^)
This patch replaces the UI-from-JSON mechanism with a more
human-friendly DSL.
The current implementation simply converts the GML into a JSON object
that can be consumed by GUI::Widget::load_from_json(). The parser is
not very helpful if you make a mistake.
The language offers a very simple way to instantiate any registered
Core::Object class by simply saying @ClassName
@GUI::Label {
text: "Hello friends!"
tooltip: ":^)"
}
Layouts are Core::Objects and can be assigned to the "layout" property:
@GUI::Widget {
layout: @GUI::VerticalBoxLayout {
spacing: 2
margins: [8, 8, 8, 8]
}
}
And finally, child objects are simply nested within their parent:
@GUI::Widget {
layout: @GUI::HorizontalBoxLayout {
}
@GUI::Button {
text: "OK"
}
@GUI::Button {
text: "Cancel"
}
}
This feels a *lot* more pleasant to write than the JSON we had. The fact
that no new code was being written with the JSON mechanism was pretty
telling, so let's approach this with developer convenience in mind. :^)