Macro layout 

macro_rules! layout {
    [ $ui:expr ,
        let $ctl:ident = Button ( $text:expr )
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Checkbox ( $text:expr $( , checked: $checked:expr )? )
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = ColorButton ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Combobox ( $( selected: $selected:expr )? )
        { $( $option:expr ),* }
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = DateTimePicker ( $kind:ident )
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = EditableCombobox ()
        { $( $option:expr ),* }
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Entry ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = FontButton ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = HorizontalSeparator ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Label ( $text:expr )
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = MultilineEntry ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = MultilineEntry ( wrapping: $wrapping:expr )
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = PasswordEntry ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = RadioButtons ( $( selected: $selected:expr )? )
        { $( $option:expr ),* }
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = SearchEntry ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Slider ( $min:expr , $max:expr )
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Spacer ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Spinbox ( $min:expr , $max:expr )
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Spinbox ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = ProgressBar ()
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Form ( $( padded: $padded:expr )? )
        { $(
            ( $strategy:ident, $name:expr ) :
            let $child:ident = $type:ident ($($opt:tt)*) $({$($body:tt)*})?
        )* }
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = Group ( $title:expr $( , margined: $margined:expr )? )
        { $(
            let $child:ident = $type:ident ($($opt:tt)*) $({$($body:tt)*})?
        )? }
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = HorizontalBox ( $( padded: $padded:expr )? )
        { $(
            $strategy:ident :
            let $child:ident = $type:ident ($($opt:tt)*) $({$($body:tt)*})?
        )* }
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = LayoutGrid ( $( padded: $padded:expr )? )
        { $(
            ( $x:expr , $y:expr ) ( $xspan:expr , $yspan:expr )
            $expand:ident ( $halign:ident , $valign:ident ) :
            let $child:ident = $type:ident ($($opt:tt)*) $({$($body:tt)*})?
        )* }
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = TabGroup ()
        { $(
            ( $name:expr $( , margined: $margined:expr )? ) :
            let $child:ident = $type:ident ($($opt:tt)*) $({$($body:tt)*})?
        )* }
    ] => { ... };
    [ $ui:expr ,
        let $ctl:ident = VerticalBox ( $( padded: $padded:expr )? )
        { $(
            $strategy:ident :
            let $child:ident = $type:ident ($($opt:tt)*) $({$($body:tt)*})?
        )* }
    ] => { ... };
}

Creates layout code from a compact, declarative and hierarchical UI description.

Example

For a more example, see the builder example application in the repository.

extern crate libui;
use libui::prelude::*;

fn main() {
    let ui = UI::init().unwrap();

    libui::layout! { &ui,
        let layout = VerticalBox(padded: true) {
            Compact: let form = Form(padded: true) {
                (Compact, "User"): let tb_user = Entry()
                (Compact, "Password"): let tb_passwd = Entry()
            }
            Stretchy: let bt_submit = Button("Submit")
        }
    }

    let mut window = Window::new(&ui, "Builder Example", 320, 200,
        WindowType::NoMenubar);

    window.set_child(layout);
    window.show();
    ui.main();
}