text: /*
  <javascriptresource>
  <menu>hide</menu>
  </javascriptresource>
  */
  
  /**
   * Set tooltip to this children.
   * @returns {Button}
   */
  Button.prototype.tip = function(text) { return _tip(this, text) }
  
  /**
   * Add children to group.
   * @returns {Button}
   */
  Group.prototype.button = function(bounds, text, properties) { return _button(this, bounds, text, properties) }
  
  /**
   * Add children to panel.
   * @returns {Button}
   */
  Panel.prototype.button = function(bounds, text, properties) { return _button(this, bounds, text, properties) }
  
  function _button(parent, bounds, text, properties) {
    var result = parent.add('button', _expandBounds(bounds), text, properties)
    if (parent.helpTips !== undefined) {
      _tip(result, parent.helpTips)
    }
    return result
  }
  