setTheme()
Description
Sets a theme of Event Calendar
Usage
setTheme(theme?: string): void;
Parameters
theme- (optional) a theme to be applied to Event Calendar. There are 3 available themes:- "material"
 - "willow"
 - "willowDark"
 
Example
// create Event Calendar
const calendar = new eventCalendar.EventCalendar("#root", {
    // initial configuration parameters
});
// set the "willow" theme
calendar.setTheme( "willow" );
Related sample: Event Calendar. Styling (Buil-in themes)