Hi Aaron,
On Mar 7, 2008, at 1:03 AM, Aaron Boodman wrote:
I've posted this to the W3C WebAPI mailing list as well. Still looking
forward to feedback on the actual content of the proposal, in either
place.
I agree with the previously stated comments that this probably doesn't
belong in HTML5, but, as you say, there isn't a better place to
discuss it at the moment -- the people who would be interested
intersect with the people who are interested in HTML5.
So, some feedback on the proposal... overall, I think that this API
should be kept as simple as possible. To that end, I would suggest:
- remove Address from Position; a separate API/spec/web service/
whichever can be used to turn a Position into an Address, without the
awkward "requestAddress" boolean flag or similar. I think this also
removes the awkward gersLocationProviderUrls? (If I'm understanding
right, these are the services that would convert position->address?)
- altitude/horizontalAccuracy/verticalAccuracy should probably use -1
if not available (using null can be awkward, since it'll become 0 in
some contexts)
- Geolocation.lastPosition should, IMO, be the only interface here
(probably Geolocation.position). It already has a timestamp, so apps
can determine when the fix is. There's no need for watchPosition/
clear given that we have setInterval/setTimeout already. An
updateInterval can be added with the minimum interval between position
updates, as a hint to applications how often it should be updating.
- I understand the desire for optionally obtaining a high accuracy
fix; I would have that be a separate method for that. For that, I can
see a callback based interface would make sense, as acquiring the fix
would take time.
- I would move heading/speed off into a separate Direction interface,
though I don't have a strong opinion about that
So, I'd suggest:
interface Position {
readonly double latitude;
readonly double longitude;
readonly double altitude;
readonly double horizontalAccuracy;
readonly double veritcalAccuracy;
readonly bool valid; // true if the fix is valid and exists; if
false, then an error message is available
readonly string errorMessage;
};
interface Geolocation {
readonly Position position;
readonly int updateInterval; // in ms
void requestHighAccuracyPosition (callback);
};
- Vlad
