The map error event sends information about the error to a callback function, including a message describing the problem encountered. By overriding this callback the developer can get access to this information and use it to make their application responsive in different ways.

First, a look at how to override the OnMapError callback during initialization of a map:

micello.maps.init (apikey, mapInit);
function  mapInit() {
    micello.maps.onMapError = onCustomMapError;
    var mapControl =  new micello.maps.MapControl('mapElement');
    var mapDataObject = mapControl.getMapData();

Then, an example of what a custom callback function might look like:

function onCustomMapError (error) {
    alert("The error was "+error);

The error string is passed into the function.

Overriding the map error will prevent the default error action from happening and no error will appear on the screen if the map encounters an issue. The message will simply be passed to the overriding function and it is the responsibility of the overriding function to display feedback to the user.