toggle-kml-layers.js

jQuery(function($){ 

	$(document.body).on("init.wpgmza", function(event) {
	
		var map		= event.map;
		var button	= $("<button type='button'>Toggle KML</button>");
		
		button.on("click", function(event) {
		
			map.kmlLayers.forEach(function(layer) {
			
				if(layer.getMap())
					layer.setMap(null);
				else
					layer.setMap(map.googleMap);
			
			});
		
		});
		
		$(map.element).before(button);
		
		
	
	});

});