Example code generated with ScriptUI Dialog Builder: https://github.com/joonaspaakko/ScriptUI-Dialog-Builder-Joonas

Dialog Example - Export Layers Inside Selected Group.jsx

/* 
Code for Import https://scriptui.joonas.me — (Triple click to select): 
{"activeId":6,"items":{"item-0":{"id":0,"type":"Dialog","parentId":false,"style":{"text":"Export Layers Inside Selected Group","preferredSize":[0,0],"margins":16,"orientation":"column","spacing":10,"alignChildren":["center","top"]}},"item-1":{"id":1,"type":"Checkbox","parentId":6,"style":{"text":"PSD","preferredSize":[0,0],"alignment":null}},"item-2":{"id":2,"type":"Checkbox","parentId":6,"style":{"text":"TIFF","preferredSize":[0,0],"alignment":null}},"item-3":{"id":3,"type":"Checkbox","parentId":6,"style":{"text":"JPEG","preferredSize":[0,0],"alignment":null,"checked":true}},"item-4":{"id":4,"type":"Checkbox","parentId":6,"style":{"text":"PNG","preferredSize":[0,0],"alignment":null}},"item-5":{"id":5,"type":"Checkbox","parentId":6,"style":{"text":"PDF","preferredSize":[0,0],"alignment":null}},"item-6":{"id":6,"type":"Panel","parentId":9,"style":{"text":"File format","preferredSize":[0,0],"margins":10,"orientation":"row","spacing":10,"alignChildren":["left","top"],"alignment":null}},"item-7":{"id":7,"type":"Panel","parentId":9,"style":{"text":"File name options","preferredSize":[0,0],"margins":10,"orientation":"column","spacing":10,"alignChildren":["left","top"],"alignment":null}},"item-8":{"id":8,"type":"EditText","parentId":14,"style":{"text":"","preferredSize":[90,0],"alignment":null}},"item-9":{"id":9,"type":"Group","parentId":0,"style":{"preferredSize":[0,0],"margins":0,"orientation":"column","spacing":10,"alignChildren":["fill","top"],"alignment":null}},"item-10":{"id":10,"type":"Group","parentId":0,"style":{"preferredSize":[0,0],"margins":0,"orientation":"row","spacing":10,"alignChildren":["left","top"],"alignment":null}},"item-11":{"id":11,"type":"Button","parentId":10,"style":{"text":"Save","justify":"center","preferredSize":[0,0],"alignment":null}},"item-12":{"id":12,"type":"Button","parentId":10,"style":{"text":"Cancel","justify":"center","preferredSize":[0,0],"alignment":null}},"item-13":{"id":13,"type":"StaticText","parentId":14,"style":{"text":"Prefix:","justify":"left","preferredSize":[0,0],"alignment":null}},"item-14":{"id":14,"type":"Group","parentId":22,"style":{"preferredSize":[0,0],"margins":0,"orientation":"column","spacing":10,"alignChildren":["left","top"],"alignment":null}},"item-15":{"id":15,"type":"Checkbox","parentId":7,"style":{"text":"Use layer name","preferredSize":[0,0],"alignment":null}},"item-16":{"id":16,"type":"Group","parentId":22,"style":{"preferredSize":[0,0],"margins":0,"orientation":"column","spacing":10,"alignChildren":["left","top"],"alignment":null}},"item-17":{"id":17,"type":"StaticText","parentId":16,"style":{"text":"Custom name:","justify":"left","preferredSize":[0,0],"alignment":null}},"item-18":{"id":18,"type":"EditText","parentId":16,"style":{"text":"File Name ","preferredSize":[160,0],"alignment":null}},"item-19":{"id":19,"type":"Group","parentId":22,"style":{"preferredSize":[0,0],"margins":0,"orientation":"column","spacing":10,"alignChildren":["left","top"],"alignment":null}},"item-20":{"id":20,"type":"StaticText","parentId":19,"style":{"text":"Suffix:","justify":"left","preferredSize":[0,0],"alignment":null}},"item-21":{"id":21,"type":"EditText","parentId":19,"style":{"text":"","preferredSize":[90,0],"alignment":null}},"item-22":{"id":22,"type":"Group","parentId":7,"style":{"preferredSize":[0,0],"margins":0,"orientation":"row","spacing":10,"alignChildren":["left","center"],"alignment":null}},"item-23":{"id":23,"type":"Divider","parentId":7,"style":false}},"order":[0,9,7,15,23,22,14,13,8,16,17,18,19,20,21,6,3,4,1,5,2,10,12,11]}
*/ 

// DIALOG
// ======
var dialog = new Window("dialog"); 
    dialog.text = "Export Layers Inside Selected Group"; 
    dialog.orientation = "column"; 
    dialog.alignChildren = ["center","top"]; 
    dialog.spacing = 10; 
    dialog.margins = 16; 

// GROUP1
// ======
var group1 = dialog.add("group"); 
    group1.orientation = "column"; 
    group1.alignChildren = ["fill","top"]; 
    group1.spacing = 10; 
    group1.margins = 0; 

// PANEL1
// ======
var panel1 = group1.add("panel"); 
    panel1.text = "File name options"; 
    panel1.orientation = "column"; 
    panel1.alignChildren = ["left","top"]; 
    panel1.spacing = 10; 
    panel1.margins = 10; 

var checkbox1 = panel1.add("checkbox"); 
    checkbox1.text = "Use layer name"; 

var divider1 = panel1.add("panel"); 
    divider1.alignment = "fill"; 

// GROUP2
// ======
var group2 = panel1.add("group"); 
    group2.orientation = "row"; 
    group2.alignChildren = ["left","center"]; 
    group2.spacing = 10; 
    group2.margins = 0; 

// GROUP3
// ======
var group3 = group2.add("group"); 
    group3.orientation = "column"; 
    group3.alignChildren = ["left","top"]; 
    group3.spacing = 10; 
    group3.margins = 0; 

var statictext1 = group3.add("statictext"); 
    statictext1.text = "Prefix:"; 

var edittext1 = group3.add("edittext"); 
    edittext1.minimumSize.width = 90; 

// GROUP4
// ======
var group4 = group2.add("group"); 
    group4.orientation = "column"; 
    group4.alignChildren = ["left","top"]; 
    group4.spacing = 10; 
    group4.margins = 0; 

var statictext2 = group4.add("statictext"); 
    statictext2.text = "Custom name:"; 

var edittext2 = group4.add("edittext"); 
    edittext2.text = "File Name "; 
    edittext2.minimumSize.width = 160; 

// GROUP5
// ======
var group5 = group2.add("group"); 
    group5.orientation = "column"; 
    group5.alignChildren = ["left","top"]; 
    group5.spacing = 10; 
    group5.margins = 0; 

var statictext3 = group5.add("statictext"); 
    statictext3.text = "Suffix:"; 

var edittext3 = group5.add("edittext"); 
    edittext3.minimumSize.width = 90; 

// PANEL2
// ======
var panel2 = group1.add("panel"); 
    panel2.text = "File format"; 
    panel2.orientation = "row"; 
    panel2.alignChildren = ["left","top"]; 
    panel2.spacing = 10; 
    panel2.margins = 10; 

var checkbox2 = panel2.add("checkbox"); 
    checkbox2.text = "JPEG"; 
    checkbox2.value = true; 

var checkbox3 = panel2.add("checkbox"); 
    checkbox3.text = "PNG"; 

var checkbox4 = panel2.add("checkbox"); 
    checkbox4.text = "PSD"; 

var checkbox5 = panel2.add("checkbox"); 
    checkbox5.text = "PDF"; 

var checkbox6 = panel2.add("checkbox"); 
    checkbox6.text = "TIFF"; 

// GROUP6
// ======
var group6 = dialog.add("group"); 
    group6.orientation = "row"; 
    group6.alignChildren = ["left","top"]; 
    group6.spacing = 10; 
    group6.margins = 0; 

var button1 = group6.add("button"); 
    button1.text = "Cancel"; 
    button1.justify = "center"; 

var button2 = group6.add("button"); 
    button2.text = "Save"; 
    button2.justify = "center"; 

dialog.show();