Specifies whether the toolbar button is selected. A toolbar button can only be selected if the AllowSelection property is True. If a toolbar button is selectable, then the Selected property can be modified to toggle the button to and from a "pushed" state.
By default, multiple toolbar buttons within the same toolbar can have their Selected property set to True at the same time. This behavior is controlled by the TToolBarMultiSelect property. If the MultiSelect property is set to True (the default), then the toolbar buttons will behave like check boxes. If the MultiSelect property is set to False, then the toolbar buttons will behave like radio buttons.