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A listener was added to “listen” to clicks on the map, and when clicked, a new marker is added with a sequential alphabet label. Another listener was added to listen to clicks on existing markers, which then shows the info window for that marker.
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A list of markers were declared with lat/long coordinates and content containing the location name. The list was looped through and each marker was added to the map. The red polyline path was drawn using a list of flightPlanCoordinates, which is just another list of lat and long coordinates. Properties of the polyline were set, such as the colour, opacity, and weight, and the flight path was set to the map. This simply connects each sequential coordinate using a red line and displays the red line on the map.
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