cordova-android/framework/assets/js/accelerometer.js
Bryce Curtis 4b3255e4fd Accelerometer updates:
- Removed thread delay to get accelerometer values.
- Override Activity lifecycle methods to manage JavaScript timers and enable window.onunload to be called.  This is needed for accelerometer to shut down correctly.
2010-08-12 10:51:12 -05:00

224 lines
7.0 KiB
JavaScript

function Acceleration(x, y, z) {
this.x = x;
this.y = y;
this.z = z;
this.timestamp = new Date().getTime();
}
/**
* This class provides access to device accelerometer data.
* @constructor
*/
function Accelerometer() {
/**
* The last known acceleration. type=Acceleration()
*/
this.lastAcceleration = null;
/**
* List of accelerometer watch listeners
*/
this.accelListeners = {};
/**
* List of accelerometer watch timers
*/
this.accelTimers = {};
/**
* Next id to use
*/
this.listenerId = 0;
/**
* Timer that turns off accelerometer when it reaches maximum time.
* This timer is only used for getCurrentAcceleration.
*/
this.turnOffTimer = 0;
// Turn off accelerometer if not accessed for certain amount of time
setInterval(function() {
navigator.accelerometer.turnOffTimer += 10;
if (navigator.accelerometer.turnOffTimer > Accelerometer.MAX_TIMER) {
Accel.stop("timer");
navigator.accelerometer.turnOffTimer = 0;
}
}, 10000);
}
Accelerometer.STOPPED = 0;
Accelerometer.STARTING = 1;
Accelerometer.RUNNING = 2;
Accelerometer.ERROR_FAILED_TO_START = 3;
Accelerometer.ERROR_NOT_FOUND = 4;
Accelerometer.ERROR_MSG = ["Not running", "Starting", "", "Failed to start", "Listener not found"];
/**
* Time (in seconds) to turn off accelerometer if getCurrentAcceleration() hasn't been called.
*/
Accelerometer.MAX_TIMER = 30;
/**
* Asynchronously aquires the current acceleration.
*
* @param {Function} successCallback The function to call when the acceleration data is available
* @param {Function} errorCallback The function to call when there is an error getting the acceleration data.
* @param {AccelerationOptions} options The options for getting the accelerometer data such as timeout.
*/
Accelerometer.prototype.getCurrentAcceleration = function(successCallback, errorCallback, options) {
// successCallback required
if (typeof successCallback != "function") {
console.log("Accelerometer Error: successCallback is not a function");
return;
}
// errorCallback optional
if (errorCallback && (typeof errorCallback != "function")) {
console.log("Accelerometer Error: errorCallback is not a function");
return;
}
// Get current acceleration status
var status = Accel.getStatus();
// If running, then call successCallback
if (status == Accelerometer.RUNNING) {
try {
navigator.accelerometer.turnOffTimer = 0;
var accel = new Acceleration(Accel.getX(), Accel.getY(), Accel.getZ());
successCallback(accel);
} catch (e) {
console.log("Accelerometer Error in successCallback: " + e);
}
}
// If not running, then start it
else {
Accel.start("timer");
navigator.accelerometer.turnOffTimer = 0;
var obj = this;
// Wait until started
var timer = setInterval(function() {
var status = Accel.getStatus();
if (status != Accelerometer.STARTING) {
clearInterval(timer);
// If accelerometer is running
if (status == Accelerometer.RUNNING) {
try {
var accel = new Acceleration(Accel.getX(), Accel.getY(), Accel.getZ());
successCallback(accel);
} catch (e) {
console.log("Accelerometer Error in successCallback: " + e);
}
}
// If accelerometer error
else {
console.log("Accelerometer Error: "+ Accelerometer.ERROR_MSG[status]);
try {
if (errorCallback) {
errorCallback(status);
}
} catch (e) {
console.log("Accelerometer Error in errorCallback: " + e);
}
}
}
}, 10);
}
}
/**
* Asynchronously aquires the acceleration repeatedly at a given interval.
*
* @param {Function} successCallback The function to call each time the acceleration data is available
* @param {Function} errorCallback The function to call when there is an error getting the acceleration data.
* @param {AccelerationOptions} options The options for getting the accelerometer data such as timeout.
* @return String The watch id that must be passed to #clearWatch to stop watching.
*/
Accelerometer.prototype.watchAcceleration = function(successCallback, errorCallback, options) {
// Default interval (10 sec)
var frequency = (options != undefined)? options.frequency : 10000;
// successCallback required
if (typeof successCallback != "function") {
console.log("Accelerometer Error: successCallback is not a function");
return;
}
// errorCallback optional
if (errorCallback && (typeof errorCallback != "function")) {
console.log("Accelerometer Error: errorCallback is not a function");
return;
}
var id = ""+(navigator.accelerometer.listenerId++);
navigator.accelerometer.accelListeners[id] = id;
Accel.start(id);
// Start watch timer
navigator.accelerometer.accelTimers[id] = setInterval(function() {
var status = Accel.getStatus();
// If accelerometer is running
if (status == Accelerometer.RUNNING) {
try {
var accel = new Acceleration(Accel.getX(), Accel.getY(), Accel.getZ());
successCallback(accel);
} catch (e) {
console.log("Accelerometer Error in successCallback: " + e);
}
}
// If accelerometer had error
else if (status != Accelerometer.STARTING) {
console.log("Accelerometer Error: "+ Accelerometer.ERROR_MSG[status]);
try {
navigator.accelerometer.clearWatch(id);
if (errorCallback) {
errorCallback(status);
}
} catch (e) {
console.log("Accelerometer Error in errorCallback: " + e);
}
}
}, (frequency ? frequency : 1));
return id;
}
/**
* Clears the specified accelerometer watch.
*
* @param {String} id The id of the watch returned from #watchAcceleration.
*/
Accelerometer.prototype.clearWatch = function(id) {
// Stop javascript timer & remove from timer list
if (id && navigator.accelerometer.accelTimers[id]) {
clearInterval(navigator.accelerometer.accelTimers[id]);
delete navigator.accelerometer.accelTimers[id];
}
// Remove from watch list
if (id && navigator.accelerometer.accelListeners[id]) {
delete navigator.accelerometer.accelListeners[id];
}
// Stop accelerometer for this watch listener
if (id) {
try {
Accel.stop(id);
} catch (e) {
}
}
}
PhoneGap.addConstructor(function() {
if (typeof navigator.accelerometer == "undefined") navigator.accelerometer = new Accelerometer();
});