A window might have a title, a caption and a border. The title is specified by the title property. The caption is specified by declaring a child component called caption. All children of the caption component will appear to the right side of the title.

<window title="Demo" border="normal" width="350px">
    <caption>    
        <toolbarbutton label="More"/>        
        <toolbarbutton label="Help"/>        
    </caption>    
    <toolbar>    
        <toolbarbutton label="Save"/>        
        <toolbarbutton label="Cancel"/>        
    </toolbar>    
    What is your favorite framework?    
    <radiogroup>    
        <radio label="ZK"/>        
        <radio label="JSF"/>        
    </radiogroup>    
    </window>    

You could also specify a label and an image to a caption, and then the appearance is as follows.

<window id="win" title="Main" border="normal" width="200px">
    <caption image="/img/coffee.gif" label="Hi there!"/>    
    <checkbox label="Hello, World!"/>    
</window>