| /* |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| */ |
| |
| var argscheck = require('cordova/argscheck'), |
| exec = require('cordova/exec'), |
| utils = require('cordova/utils'), |
| CompassHeading = require('./CompassHeading'), |
| CompassError = require('./CompassError'), |
| |
| timers = {}, |
| eventTimerId = null, |
| compass = { |
| /** |
| * Asynchronously acquires the current heading. |
| * @param {Function} successCallback The function to call when the heading |
| * data is available |
| * @param {Function} errorCallback The function to call when there is an error |
| * getting the heading data. |
| * @param {CompassOptions} options The options for getting the heading data (not used). |
| */ |
| getCurrentHeading:function(successCallback, errorCallback, options) { |
| argscheck.checkArgs('fFO', 'compass.getCurrentHeading', arguments); |
| |
| var win = function(result) { |
| var ch = new CompassHeading(result.magneticHeading, result.trueHeading, result.headingAccuracy, result.timestamp); |
| successCallback(ch); |
| }; |
| var fail = errorCallback && function(code) { |
| var ce = new CompassError(code); |
| errorCallback(ce); |
| }; |
| |
| // Get heading |
| exec(win, fail, "Compass", "getHeading", [options]); |
| }, |
| |
| /** |
| * Asynchronously acquires the heading repeatedly at a given interval. |
| * @param {Function} successCallback The function to call each time the heading |
| * data is available |
| * @param {Function} errorCallback The function to call when there is an error |
| * getting the heading data. |
| * @param {HeadingOptions} options The options for getting the heading data |
| * such as timeout and the frequency of the watch. For iOS, filter parameter |
| * specifies to watch via a distance filter rather than time. |
| */ |
| watchHeading:function(successCallback, errorCallback, options) { |
| argscheck.checkArgs('fFO', 'compass.watchHeading', arguments); |
| // Default interval (100 msec) |
| var frequency = (options !== undefined && options.frequency !== undefined) ? options.frequency : 100; |
| var filter = (options !== undefined && options.filter !== undefined) ? options.filter : 0; |
| |
| var id = utils.createUUID(); |
| if (filter > 0) { |
| // is an iOS request for watch by filter, no timer needed |
| timers[id] = "iOS"; |
| compass.getCurrentHeading(successCallback, errorCallback, options); |
| } else { |
| // Start watch timer to get headings |
| timers[id] = window.setInterval(function() { |
| compass.getCurrentHeading(successCallback, errorCallback); |
| }, frequency); |
| } |
| |
| if (cordova.platformId === 'browser' && !eventTimerId) { |
| // Start firing deviceorientation events if haven't already |
| var deviceorientationEvent = new Event('deviceorientation'); |
| eventTimerId = window.setInterval(function() { |
| window.dispatchEvent(deviceorientationEvent); |
| }, 200); |
| } |
| |
| return id; |
| }, |
| |
| /** |
| * Clears the specified heading watch. |
| * @param {String} id The ID of the watch returned from #watchHeading. |
| */ |
| clearWatch:function(id) { |
| // Stop javascript timer & remove from timer list |
| if (id && timers[id]) { |
| if (timers[id] != "iOS") { |
| clearInterval(timers[id]); |
| } else { |
| // is iOS watch by filter so call into device to stop |
| exec(null, null, "Compass", "stopHeading", []); |
| } |
| delete timers[id]; |
| |
| if (eventTimerId && Object.keys(timers).length === 0) { |
| // No more watchers, so stop firing 'deviceorientation' events |
| window.clearInterval(eventTimerId); |
| eventTimerId = null; |
| } |
| } |
| } |
| }; |
| |
| module.exports = compass; |