To round off our chapter on vector styles, let's explore combining vector styles with user interaction. In the previous chapter, we responded to the mouse moving over a country by displaying the country's name in an HTML element outside the map. We'll build on this example and take it one step further. As the mouse moves, we'll highlight the country under the mouse and draw its flag and name in the center of the country using a feature overlay. The feature overlays are something new; so, we'll need to learn something about them before we go ahead with our example though.
The FeatureOverlay
class, ol.FeatureOverlay
, is a special type of vector layer designed to render a small number of temporary features in a specific style. It isn't a full-fledged vector layer, but it is highly optimized for the specific case of highlighting features in a temporary way. This sounds ideal for our use case!
Creating a new feature overlay is just like creating any other...