:bind(id, event)

xml
<?xml version="1.0" encoding="utf-8" ?>
<vbox>
    <hslider id="xpos" />
    <hslider id="ypos" />
    <hslider id="zpos" />
    <checkbox id="boolInput" />
    <textfield id="stringInput" />
</vbox>

haxe
import haxe.ui.containers.Box;
import haxe.ui.events.UIEvent;

typedef Data = {
    @:optional public var x:Float;
    @:optional public var y:Float;
    @:optional public var z:Float;
    @:optional public var check:Bool;
    @:optional public var text:Float;
}

@:build(haxe.ui.macros.ComponentMacros.build("assets/test_c.xml"))
class TestComponent extends Box {
    private var _data:Data = {};
    
    public function new() {
        super();
    }
    
    @:bind(xpos, UIEvent.CHANGE)
    @:bind(ypos, UIEvent.CHANGE)
    @:bind(zpos, UIEvent.CHANGE)
    @:bind(boolInput, UIEvent.CHANGE)
    @:bind(stringInput, UIEvent.CHANGE)
    private function onValueChanged(e:UIEvent) {
        switch (e.target.id) {
            case "xpos":
                _data.x = e.target.value;
            case "ypos":
                _data.y = e.target.value;
            case "zpos":
                _data.z = e.target.value;
            case "boolInput":
                _data.check = e.target.value;
            case "stringInput":
                _data.text = e.target.value;
        }
        
        trace(_data);
    }
}