Mapping directions in a JavaFX application is easy with the Directions API that was recently introduced in GMapsFX. In this blog post I’ll walk through an example of setting up an application with a map and a couple of text fields, one which will be used for the trip origin and the second which will be used for the trip destination. When the user hits ‘Enter’ in the destination text field, the map will display the directions.
Starting off with the FXML file, we have an AnchorPane which contains the GoogleMapView and 2 TextFields. The AnchorPane has a controller assigned to it named FXMLController, and both components have an FX ID associated with them so they will be accessible from the FXMLController class. Also, the destination TextField has an action, “toTextFieldAction” associated with it, so this method will be called when the user hits the ‘Enter’ key in the TextField.
The result should look as follows:
Next, I’ve cut up the relevant parts of the FXMLController class. The MapComponentInitializedListener interface needs to be implemented by the controller since the underlying GoogleMap doesn’t get initialized immediately. The DirectionsServiceCallback interface also needs to be implemented, although in this example I won’t be doing anything with it.
The GoogleMapView and the TextFields components from the FXML file are defined below and annotated with @FXML.
There is also a reference to the Directions Service as well as StringProperties to represent the ‘to’ and ‘from’ endpoints that the user will enter.
After the controller is created, its initialize method is called which will set the MapView’s initialization listener to the FXMLController as well as bind the ‘to’ and ‘from’ String properties to the TextProperties of their respective TextFields.
Once the map has been initialized, the DirectionService can be instantiated as well as a MapOptions object to set various attributes about the map. The options are then configured and a GoogleMap object can be instantiated from the map view. The directionsPane is a component which can be used to render the step by step direction text, in this example however, it won’t be displayed.
Finally, the action method defined in the FXML file when the user hits ‘Enter’ in the TextField is below. The method will call the getRoute() method on the DirectionsService class, passing in a boolean value which will define whether the route can be modified by dragging it, the map object, and the DirectionsRequest object.
Below is an example when the user enters directions from Seattle to Redmond
That’s it! For completeness I’ll include the full source code of the example below.