In your map layers and filters you can use variables provided as URL parameters - to automatically configure the map by providing appropriate values when opening Mapsly by a custom link. This is especially useful when used in shared maps to restrict access to data, for example when embedding Mapsly in a customer portal.

To use a URL parameter in a map layer or filter, in its formula select the URL parameter as the right operand of an expression:

and type the desired name of your URL parameter in the Insert URL parameter pop-up:

Now, if you pass this URL parameter when opening Mapsly, it will be to evaluate your map layers/filters' formulas.

IMPORTANT! If the URL parameter is omitted, or has an empty or null value, Mapsly removes the condition that uses this parameter from the formula, effectively always evaluating it to true. And when a URL parameter is used with shared maps to restrict access to data, manually altering or omitting it may have undesired results like revealing records that were supposed to be filtered out. To prevent unauthorized alteration of URL parameters and the shared map's ID in the URL, use an URL signature in your shared map URL.