Plotting a Location on a Map
The latitude and longitude don’t tell you a whole lot, so one of the first things you must do is plot the location on a map. To do this you need access to a map API. Google Maps is one of the most popular map APIs and provides two different APIs: a static map API and the traditional interactive map you are probably familiar with.
Generating static maps is easy. All it involves is sending a properly formed request in the form of an <img> tag src to Google, which returns an image to you. The API for static maps is available at https://developers.google.com/maps/documentation/staticmaps/.
If you want a map with a marker at a specific location, you need to generate a URL with the size of the output image, the marker, and a value for the sensor option, which lets Google know whether this application uses a sensor to determine the position. (This field is required.) You also need to pass a zoom value to control how zoomed in the resultant image is.
Markers are defined by a number of attributes separated by pipe characters (|), for example:
markers=color:red||label:A|lat,longBecause this needs to be encoded into a URL, the pipe character is URL encoded into the string %7C.
Listing 23-2 shows the first example modified to output a static map at your location. Desktop browsers have wildly varying levels of accuracy, so it may show a location that’s only a rough approximation of your actual location.
Listing 23-2: Static map
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