Programmatically place button at (x,y)

Since my menu will have a variable number of options, I need to programmatically position them. However, I don’t get it to work.

        buttons.add(new ButtonBuilder("button_" + name, name) {
        {
            height("15%");
            width("15%");
            backgroundColor(Color.randomColor());
            
            //alignCenter(); // works but I need more than three options
            
            // align(Align.valueOf("10px")); // IllegalArgumentException
            
            // x("10px"); // does nothing
            
            // set("x", "10px"); // does nothing                    
        }
    });

How can I position it programmatically at (x, y)?

Okay, I found it out myself.

childLayoutAbsoluteInside() is needed in parent.

panel(new PanelBuilder("OPTIONS") {
                        {
                            childLayoutAbsoluteInside();
                            control(new ButtonBuilder("button_" + name, name) {
        {
            height("15%");
            width("20%");
            
            backgroundColor(Color.randomColor());
                           
            switch (buttonCount) {
                case 1: x("0%");y("20%"); break;
                case 2: x("40%");y("0%"); break;
                case 3: x("90%");y("20%"); break;
            }             
        }
    });                                
                        }
                    });