Peter Lubbers - Pro HTML 5 Programming

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CHAPTER 4 ■ USING THE HTML5 GEOLOCATION API
Figure 4-2. The notification bar is triggered in Firefox when the HTML5 Geolocation APIs are used
The mechanism is triggered when the HTML5 Geolocation code is executed. Simply adding HTML5
Geolocation code that is not called anywhere (as, for example, in an onload method) does not do
anything. If, however, the HTML5 Geolocation code is executed, for example, in a call to
navigator.geolocation.getCurrentPosition (explained in more detail later on), the user is prompted to
share their location with the application. Figure 4-3 shows what happens on Safari, running on an
iPhone.
Figure 4-3. The notification dialog box is triggered in Safari when the HTML5 Geolocation APIs are used
Apart from providing the necessary mechanism to request permission to share your location, some
implementations (Firefox, for example) also allow you to remember the permission granted to the site
for the next time you enter. This is similar to how you can remember passwords for certain sites in your
browser.