<div id="map"></div>
<script>
$("#map").kendoMap({
    layers: [{
        type: "shape",
        dataSource: {
            type: "geojson",
            data: [{
                "type": "Polygon",
                "coordinates": [
                    [[30, 10], [40, 40], [20, 40], [10, 20], [30, 10]]
                ]
            }]
        }
    }]
});

var map = $("#map").data("kendoMap");
var shapeLayer = map.layers[0];

// Hide the layer first
shapeLayer.hide();

// Show the layer
setTimeout(function() {
    shapeLayer.show();
    console.log("Shape layer is now visible");
}, 1000);
</script>