Geolocation
Common sources of location information include Global Positioning System (GPS) and location inferred from network signals such as IP address, RFID, WiFi and Bluetooth MAC addresses, and GSM/CDMA cell IDs.
This API is based on the W3C Geolocation API Specification.
The Coordinates object is created and populated by Cordova, and attached to the Position object. The Position object is then returned to the user through a callback function.
The Positon object contains Position coordinates and timestamp, created by the geolocation API.
A PositionError object is returned to the geolocationError callback when an error occurs.Error code:{{{ PositionError.PERMISSION_DENIED PositionError.POSITION_UNAVAILABLE PositionError.TIMEOUT }}}
enableHighAccuracy: Provides a hint that the application would like to receive the best possible results. By default, the device will attempt to retrieve a Position using network-based methods. Setting this property to true tells the framework to use more accurate methods, such as satellite positioning.
问题：
- 如果没有开启GPS，甚至没有开启移动网络，phonegap接口是否仍然能够定位？《百度地图》这个应用在没有开启上述两个功能的情况下也能够比较准确的定位，使用的是什么办法，是基站吗？
- enableHighAccuracy这个参数是用来提高定位精度的，默认设备是使用network-based methods，这是指上面提到的location inferred from network signals吗？是否包括GPS定位？后面提到的statellite positoning（卫星定位）是指什么，和GPS定位有什么区别。
- W3C Geolocation API Specification具体的内容是什么？HTML5标准中是否有此定义。
Domain Whitelist Guide
whitelist:列入优良者名单
每一个平台上的实现不一样，暂时没有按照W3C的标准设计。
Android平台的实现：The whitelisting rules are found in res/xml/cordova.xml and declared with the element <access origin="..." />.
This is called a single origin policy―you can read further about single origin policies at http://en.wikipedia.org/wiki/Same_origin_policy . The same is not true for a PhoneGap applicat ion. A PhoneGap app lication bundles the required HTML, JavaScript, and CSS files, and PhoneGap applications do not have domains like “abc.com.” This allows PhoneGap to be a platform for the easy development of mashups, whi ch can freely make Ajax calls to various other sites. Think about your PhoneGap app lication integrating Facebook, Twitter, and Flickr all into one mashup, with just a few lines of JavaScript code. This makes PhoneGap an ideal platform for creating mobile applications for the web services listed on programmableweb.com.