The mouseover is a popup window that is displayed after clicking on features on the map.
If no mouseover content is set in the layer configuration, no popup is displayed when clicking on a feature of that layer.
You can set your own mouseover content programatically in Javascript. For instance, you can add a mouseover on a layer that has no mousoever content in its configuration.
In the following example, the layer "Hydrography", id=3, has no mouseover defined.
We will set a custom mouseover content that:
Always displays a custom header
Displays the mouseover content for a clicked hydrography feature
Avoids displaying a mouseover for the "Event" layer (blue dots on the map)
<!DOCTYPEhtml><html> <head> <metahttp-equiv="Content-Type"content="text/html;charset=UTF-8"> <metacharset="UTF-8"> <style>#my-custom-map {width:600px;height:600px;border:1px solid grey; } </style> </head> <bodyclass="jmap_wrapper"> <divid="my-custom-map"></div> <scripttype="text/javascript">constHYDRO_LAYER_ID=3;constPLACE_LAYER_ID=6;window.JMAP_OPTIONS= { projectId:1, restBaseUrl:"https://jmapdoc.jmaponline.net/services/rest/v2.0", anonymous:true, map: { containerId:"my-custom-map", zoom:13.797865986918877, center: { x:-73.48063889179525, y:45.664231577062765 } }, extensions: [{ id:"custom-mouseover-extension",initFn: () => {JMap.Event.MouseOver.on.beforeContentProcessed("My-custom-mouse-over", params => {const {selection,getFeaturesByLayerId,addHtmlContentAtTheBeginning,addHtmlContentAtTheEnd,removeFeaturesFromLayerSelection } = params;/* this method is processed each time we click on features on the map, even if no mouse-over is defined for a layer *//* add a message in the top of the mouseover popup */addHtmlContentAtTheBeginning(`<span style="font-size: 1rem">Custom popup header visible for all layers</span>`);/* add a message in the bottom of the mouseover popup */addHtmlContentAtTheEnd(`<span style="font-size: 1rem">Custom popup footer visible for all layers</span>`);console.info("All selected features", { ...selection });/* if some place feature has been selected, remove it from the mouseover */removeFeaturesFromLayerSelection(PLACE_LAYER_ID,getFeaturesByLayerId(PLACE_LAYER_ID).map(f =>f.id));console.info("Selected hydrography features",getFeaturesByLayerId(HYDRO_LAYER_ID)); }) },renderMouseOver: (layer, feature) => {/* this method is processed for each feature that has been clicked */if (layer.id !==HYDRO_LAYER_ID) {return; }return { html:` <div style="display: flex; flex-direction: column; align-items: center;"> <span> Hydro feature id="${feature.id}" clicked ! </span> <button onclick="alert('Feature id=${feature.id} clicked !')" style="cursor: pointer; border: 1px solid grey; margin: .5rem;"> Click me ! </button> </div>` }; } }] } </script> <scriptdefertype="text/javascript"src="https://cdn.jsdelivr.net/npm/jmap-core-js@7_Kathmandu_HF3"></script> </body></html>