Sean Nikolai Fridman created CB-1462:
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             Summary: False logic for native watchPosition/clearWatch
                 Key: CB-1462
                 URL: https://issues.apache.org/jira/browse/CB-1462
             Project: Apache Cordova
          Issue Type: Bug
          Components: Android, CordovaJS
    Affects Versions: 2.0.0
            Reporter: Sean Nikolai Fridman
            Assignee: Joe Bowser


Note: This is a bug in Android's native geolocation implementation. I can't 
speak to what happens on other platforms. However, I get the feeling that the 
bug is symptomatic of the JS implementation so it might very well exist not 
only on Android.

Description: When watchPosition is called, it first calls getCurrentLocation 
(resulting in a native call to getLocation), then makes a native call to 
addWatch. In Android, addWatch callback ids and getLocation callback ids are 
stored in separate data structures. The bug I'm seeing is, when I call 
clearWatch before the watch operation's implicit getCurrentLocation callback is 
invoked, the watch operation is removed/stopped in native, but the 
corresponding getCurrentLocation operation is not.  This is not compliant with 
the W3C spec, which states that that no further callbacks for the watch 
operation should be invoked. Worse, this causes a bug on Android where GPS is 
never shut off! clearWatch stops the location listener *iff* {{callbacks.size + 
watches.size == 0}}, and so if the callback hadn't been invoked yet...

_(Actually, skimming back through the code, I'm not seeing anywhere where the 
location listener is stopped after a getCurrentPosition. Which may be another 
issue... not sure.)_

And the potential issue in Javascript is this: if native has no knowledge of 
which getCurrentLocation callbacks are part of a watch operation and which are 
just normal independent ones, how can it possibly remove the callback id for 
the implicit getCurrentLocation operation on clearWatch? And how can it 
possibly know if it can really stop listening for location updates?

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