react-native/Libraries/Geolocation/Geolocation.js

161 lines
4.9 KiB
JavaScript

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @providesModule Geolocation
* @flow
*/
'use strict';
const NativeEventEmitter = require('NativeEventEmitter');
const RCTLocationObserver = require('NativeModules').LocationObserver;
const invariant = require('fbjs/lib/invariant');
const logError = require('logError');
const warning = require('fbjs/lib/warning');
const LocationEventEmitter = new NativeEventEmitter(RCTLocationObserver);
var subscriptions = [];
var updatesEnabled = false;
type GeoOptions = {
timeout: number,
maximumAge: number,
enableHighAccuracy: bool,
distanceFilter: number,
}
/**
* The Geolocation API extends the web spec:
* https://developer.mozilla.org/en-US/docs/Web/API/Geolocation
*
* As a browser polyfill, this API is available through the `navigator.geolocation`
* global - you do not need to `import` it.
*
* ### Configuration and Permissions
*
* <div class="banner-crna-ejected">
* <h3>Projects with Native Code Only</h3>
* <p>
* This section only applies to projects made with <code>react-native init</code>
* or to those made with Create React Native App which have since ejected. For
* more information about ejecting, please see
* the <a href="https://github.com/react-community/create-react-native-app/blob/master/EJECTING.md" target="_blank">guide</a> on
* the Create React Native App repository.
* </p>
* </div>
*
* #### iOS
* You need to include the `NSLocationWhenInUseUsageDescription` key
* in Info.plist to enable geolocation when using the app. Geolocation is
* enabled by default when you create a project with `react-native init`.
*
* In order to enable geolocation in the background, you need to include the
* 'NSLocationAlwaysUsageDescription' key in Info.plist and add location as
* a background mode in the 'Capabilities' tab in Xcode.
*
* #### Android
* To request access to location, you need to add the following line to your
* app's `AndroidManifest.xml`:
*
* `<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />`
*
* Android API >= 18 Positions will also contain a `mocked` boolean to indicate if position
* was created from a mock provider.
*
*/
var Geolocation = {
/*
* Invokes the success callback once with the latest location info. Supported
* options: timeout (ms), maximumAge (ms), enableHighAccuracy (bool)
* On Android, if the location is cached this can return almost immediately,
* or it will request an update which might take a while.
*/
getCurrentPosition: function(
geo_success: Function,
geo_error?: Function,
geo_options?: GeoOptions
) {
invariant(
typeof geo_success === 'function',
'Must provide a valid geo_success callback.'
);
RCTLocationObserver.getCurrentPosition(
geo_options || {},
geo_success,
geo_error || logError
);
},
/*
* Invokes the success callback whenever the location changes. Supported
* options: timeout (ms), maximumAge (ms), enableHighAccuracy (bool), distanceFilter(m)
*/
watchPosition: function(success: Function, error?: Function, options?: GeoOptions): number {
if (!updatesEnabled) {
RCTLocationObserver.startObserving(options || {});
updatesEnabled = true;
}
var watchID = subscriptions.length;
subscriptions.push([
LocationEventEmitter.addListener(
'geolocationDidChange',
success
),
error ? LocationEventEmitter.addListener(
'geolocationError',
error
) : null,
]);
return watchID;
},
clearWatch: function(watchID: number) {
var sub = subscriptions[watchID];
if (!sub) {
// Silently exit when the watchID is invalid or already cleared
// This is consistent with timers
return;
}
sub[0].remove();
// array element refinements not yet enabled in Flow
var sub1 = sub[1]; sub1 && sub1.remove();
subscriptions[watchID] = undefined;
var noWatchers = true;
for (var ii = 0; ii < subscriptions.length; ii++) {
if (subscriptions[ii]) {
noWatchers = false; // still valid subscriptions
}
}
if (noWatchers) {
Geolocation.stopObserving();
}
},
stopObserving: function() {
if (updatesEnabled) {
RCTLocationObserver.stopObserving();
updatesEnabled = false;
for (var ii = 0; ii < subscriptions.length; ii++) {
var sub = subscriptions[ii];
if (sub) {
warning('Called stopObserving with existing subscriptions.');
sub[0].remove();
// array element refinements not yet enabled in Flow
var sub1 = sub[1]; sub1 && sub1.remove();
}
}
subscriptions = [];
}
}
};
module.exports = Geolocation;