with (Maplets[Elements]):
maplet := 
Maplet('onstartup'='Action1','reference'='Maplet1',
	Action('reference'='clickButton1',
		Evaluate('function'='sum(TextField1,k = TextField2 .. TextField3)','target'='MathMLViewer1','waitforresult'='true')),
	Action('reference'='clickButton2'),
	MathMLViewer('background'="#FFFFFF",'fontsize'='18','foreground'="#000000",'height'='100','reference'='MathMLViewer1','width'='300'),
	Label('background'="#D6D3CE",'caption'="Zadejte argument sumy (např.:2*k^2)",'enabled'='true','foreground'="#000000",'reference'='Label1','visible'='true'),
	TextField('background'="#FFFFFF",'editable'='true','enabled'='true','foreground'="#000000",'halign'='left','reference'='TextField1','visible'='true','width'='20'),
	Label('background'="#D6D3CE",'caption'="od",'enabled'='true','foreground'="#000000",'reference'='Label2','visible'='true'),
	TextField('background'="#FFFFFF",'editable'='true','enabled'='true','foreground'="#000000",'halign'='left','reference'='TextField2','visible'='true','width'='20'),
	Label('background'="#D6D3CE",'caption'="do",'enabled'='true','foreground'="#000000",'reference'='Label3','visible'='true'),
	TextField('background'="#FFFFFF",'editable'='true','enabled'='true','foreground'="#000000",'halign'='left','reference'='TextField3','visible'='true','width'='20'),
	Button('background'="#D6D3CE",'caption'="Suma",'enabled'='true','foreground'="#000000",'onclick'='clickButton1','reference'='Button1','visible'='true'),
	Button('background'="#D6D3CE",'caption'="Konec",'enabled'='true','foreground'="#000000",'onclick'='clickButton2','reference'='Button2','visible'='true'),
	BoxLayout('background'="#D6D3CE",'border'='false','halign'='center','inset'='5','reference'='BoxLayout2','valign'='center','vertical'='true','visible'='true',
		BoxRow(
			BoxCell('hscroll'='never','value'='Button1','vscroll'='never'),
			BoxCell('hscroll'='never','value'='Button2','vscroll'='never'))),
	BoxLayout('background'="#D6D3CE",'border'='false','halign'='center','inset'='5','reference'='BoxLayout1','valign'='center','vertical'='false','visible'='true',
		BoxColumn(
			BoxColumn(
				BoxCell('hscroll'='never','value'='MathMLViewer1','vscroll'='never')),
			BoxColumn(
				BoxRow(
					BoxCell('hscroll'='never','value'='Label1','vscroll'='never'),
					BoxCell('hscroll'='never','value'='TextField1','vscroll'='never')),
				BoxRow(
					BoxCell('hscroll'='never','value'='Label2','vscroll'='never'),
					BoxCell('hscroll'='never','value'='TextField2','vscroll'='never'),
					BoxCell('hscroll'='never','value'='Label3','vscroll'='never'),
					BoxCell('hscroll'='never','value'='TextField3','vscroll'='never'))),
			BoxColumn(
				BoxCell('hscroll'='never','value'='BoxLayout2','vscroll'='never')))),
	Window('layout'='BoxLayout1','reference'='Window1','resizable'='true','title'="Maplet"),
	Action('reference'='Action1',
		RunWindow('window'='Window1')),
	Font('bold'='false','family'="times",'italic'='false','reference'='Font1','size'='12')):

Maplets[Display](maplet);