CHAPTER 8 EXERCISE SOLUTIONS
Exercise 1 Solution
The most appropriate answer is b. Answer c is also correct, but it's far too narrow a definition because web services can do much more.
Exercise 2 Solution
To start with, you would use location services only if requested, perhaps with a “near me” link. You might provide other options, such as letting users choose from a list of locations. You would then perform a one-shot location detection to locate nearby restaurants, and then you'd shut off the location service again. Default accuracy would be enough for this. If you were to also provide route-finding functionality to help users find restaurants, you might use high accuracy and keep the location service running while the user gets to the location.
Exercise 3 Solution
You use the GeoCoordinateWatcher class for obtaining location information.
Exercise 4 Solution
You use the GeoCoordinate.GetDistanceTo() method, which gets the distance between two GeoCoordinate instances, in meters.
Exercise 5 Solution
Before using the Bing Maps Silverlight control, you must obtain a usage key.
Exercise 6 Solution
You use the Scale class, which you would include in XAML as follows:
<m:Map CredentialsProvider=“<My Key>” <m:Map.Children> <o:Scale /> </m:Map.Children> </m:Map>
This code assumes the following namespaces:
xmlsn:m=“clr-namespace:Microsoft.Phone.Controls.Maps; assembly=Microsoft.Phone.Controls.Maps” xmlsn:o=“clr-namespace:Microsoft.Phone.Controls.Maps.Overlays; assembly=Microsoft.Phone.Controls.Maps” ...