I am trying to get the absolute device orientation across different mobile devices (android + IOs) and browsers
in a more or less reliable way. I would rather be able to understand if the orientation I am receiving is relative and not show the compass instead of showing wrong values.
I have been googling back and forth for days and I haven't found a definitive answer yet (I am
a javascript and web dev novice).
I see that the Full-Tilt library should be doing exactly
that but it has a non commercial license. I intend to use this result in a potentially commercial project, moreover, I would like to understand what's happening.
Nowadays most deviceorientation events are returning relative values.
deviceorientationabsolute is not supported by firefox and it's an experimental feature, I can fallback on it when other things fail but it cannot be the main solution.
So far I've got to this line of reasoning (pseudocode):
if(mobile)
if(webkitmobilecompassheading)
window.addEventListener("deviceorientation", handleOrientationWebkit, true);
else if(deviceorientationabsolute)
window.addEventListener("deviceorientation", handleOrientationAbsolute, true);
else
"bad luck"
I have no idea where to look to understand how many devices I would miss out on with the following reasoning, and if there is a better way.
For Android it works auto, for iOS it needs to be clicked to start it.
Here's a part of code you can use for that
startBtn.addEventListener("click", startCompass);
function startCompass() {
if (isIOS) {
DeviceOrientationEvent.requestPermission()
.then((response) => {
if (response === "granted") {
window.addEventListener("deviceorientation", handler, true);
} else {
alert("has to be allowed!");
}
})
.catch(() => alert("not supported"));
} else {
window.addEventListener("deviceorientationabsolute", handler, true);
}
}
function handler(e) {
const degree = e.webkitCompassHeading || Math.abs(e.alpha - 360);
}
Full tutorial is here, try demo also
https://dev.to/orkhanjafarovr/real-compass-on-mobile-browsers-with-javascript-3emi
Related
I'm trying to create a script which will run when any browser console is opened or closed. Is there any way to detect if the browser console in all browsers (Firefox/IE/Chrome/Safari/Opera) is open or not via JavaScript, jQuery, or any other client-side script?
If you are willing to accept an interference for the user,
you could use the debugger statement, as it is available in all major browsers.
Side note: If the users of your app are interested in console usage, they're probably familiar with dev tools, and will not be surprised by it showing up.
In short, the statement is acting as a breakpoint, and will affect the UI only if the browser's development tools is on.
Here's an example test:
<body>
<p>Devtools is <span id='test'>off</span></p>
<script>
var minimalUserResponseInMiliseconds = 100;
var before = new Date().getTime();
debugger;
var after = new Date().getTime();
if (after - before > minimalUserResponseInMiliseconds) { // user had to resume the script manually via opened dev tools
document.getElementById('test').innerHTML = 'on';
}
</script>
</body>
devtools-detect should do the job. Try the simple demo page.
devtools-detect → detect whether DevTools is open, and its orientation.
Supported Browsers:
DevTools in Chrome, Safari, Firefox & Opera
Caveats:
Doesn't work if DevTools is undocked (separate window), and may show a false positive if you toggle any kind of sidebar.
I don't think it is directly possible in JS for security reasons.But in here
they are claiming that it is possible and is useful for when you want something special to happen when DevTools is open. Like pausing canvas, adding style debug info, etc.
But As #James Hill tell in this, I also thinks even if a browser chose to make this information accessible to the client, it would not be a standard implementation (supported across multiple browsers).
Also can also try this one also here.
It's not possible in any official cross browser way, but if the occasional false positive is acceptable, you can check for a window.onresize event. Users resizing their windows after loading a page is somewhat uncommon. It's even more effective if you expect users will be frequently opening the console, meaning less false positives as a percentage.
window.onresize = function(){
if ((window.outerHeight - window.innerHeight) > 100) {
// console was opened (or screen was resized)
}
}
Credit to https://stackoverflow.com/a/7809413/3774582. Although that question is chrome specific, the concept applies here.
To expand on this, if you need a very low tolerance on false positives, most window resizes will trigger this event dozens of times because it is usually done as a drag action, while opening the console will only trigger this once. If you can detect this, the approach will become even more accurate.
Note: This will fail to detect if the console is already open when the user visits the page, or if the user opens the console in a new window.
(function() {
'use strict';
const el = new Image();
let consoleIsOpen = false;
let consoleOpened = false;
Object.defineProperty(el, 'id', {
get: () => {
consoleIsOpen = true;
}
});
const verify = () => {
console.dir(el);
if (consoleIsOpen === false && consoleOpened === true) {
// console closed
window.dispatchEvent(new Event('devtools-opened'));
consoleOpened = false;
} else if (consoleIsOpen === true && consoleOpened === false) {
// console opened
window.dispatchEvent(new Event('devtools-closed'));
consoleOpened = true;
}
consoleIsOpen = false;
setTimeout(verify, 1000);
}
verify();
})();
window.addEventListener('devtools-opened', ()=>{console.log('opened')});
window.addEventListener('devtools-closed', ()=>{console.log('closed')});
Here is a code that worked for me.
This solution works like a charm
https://github.com/sindresorhus/devtools-detect
if you are not using modules - disable lines
// if (typeof module !== 'undefined' && module.exports) {
// module.exports = devtools;
// } else {
window.devtools = devtools;
// }
and result is then here
window.devtools.isOpen
I for my project use the blur event.
function yourFunction() {}
window.addEventListener('blur',(e)=>{e.preventDefault(); yourFunction()})
This will execute yourFunction when the window loses focus.
For instance when someone opens the DevTools.
Okay seems like it also fires when you try to access a different window... so maybe not the best solution.
Maybe pair it with looking at the width of the browser.
If it chainged you can be pretty sure about it I think
has anyone noticed that on the last version of Desktop Firefox, it is recognized as a touch device?
I am using the script below:
function isTouch() {
try{ document.createEvent("TouchEvent"); return true; }
catch(e){ return false;
}
}
if (isTouch()) {
alert('I am touch device!')
}
The script has given me flawless results up until the latest version of Desktop Firefox. Is it a bug? Am I missing something?
Thanks everyone for your time!
edit: False alarm people. I have no idea what went wrong, I tried resetting preferences, disabled all extensions but had no luck.
I finally solved the issue by REFRESHING firefox (lost all my extensions though and had to reinstall).
Thanks for everybody's efforts and sorry for any inconvenience caused.
You are just checking if you can create a specific type of event, not really if you are currently on a touch device.
Here is a more complete isTouchDevice function, which I wrote some time ago based on the core of Modernizr.
/**
* Detect if the current device is a touch device.
* Inspired by Modernizr and hardcore streamlined.
*/
function isTouchDevice() {
var bool;
if( ('ontouchstart' in window) || window.DocumentTouch && document instanceof DocumentTouch ) {
bool = true;
}
else {
var fakeBody = document.createElement( 'fakebody' );
fakeBody.innerHTML += '<style>#media (touch-enabled),(-webkit-touch-enabled),(-moz-touch-enabled),(-o-touch-enabled){#touchtest{top:42px;position:absolute}}</style>';
document.documentElement.appendChild( fakeBody );
var touchTestNode = document.createElement( 'div' );
touchTestNode.id = 'touchtest';
fakeBody.appendChild( touchTestNode );
bool = touchTestNode.offsetTop === 42;
}
return bool;
}
I've had a similar problem, and maybe some people will benefit from the information.
In my case, the Touch events were always detected as positive by Modernizr in Firefox desktop, even if they weren't fired.
In the end, I realized that 'dom.w3c_touch_events.enabled' had a value of '1' even if I didn't set it myself.
It was actually switched on by the "Touch" button in Responsive Design View, but never switched back to '0' even after disabling the Touch events with the very same button.
So I've reported a bug to Mozilla : https://bugzilla.mozilla.org/show_bug.cgi?id=1188270
You will find a test case there.
Basically, the only solution I had to go back to normal is to change manually the value of 'dom.w3c_touch_events.enabled' to '0' in 'about:config'.
And I'm now aware that by enabling Touch events in the Responsive Design View, I will have to manually switch it back after.
Hope this can help some people !
How to check if device is Windows Surface Tablet and browser is chrome or IE using Javascript.
i have tried following code
function is_touch_device()
{
try {
document.createEvent("TouchEvent");
return true;
} catch (e) {
return false;
}
}
if(is_touch_device() )
{
if(navigator.userAgent.toLowerCase().indexOf('chrome')>-1)
{
//some stuff
}
}
i have searched for useragent
but i an not getting exact for surface.
how to check if device is surface and browser is chrome or IE
Using the navigator object you can access these data fields
navigator.appName <- gets app name may be misleading so also get the appCodeName
navigator.appCodeName; <-- alternate name
navigator.platform; <-- platform the user is on
http://www.w3schools.com/js/js_window_navigator.asp
window.navigator.pointerEnabled
This method returned true Surface devices.....
Though you can use navigator object to serve your purpose, I would suggest you to use modernizer for the same.
A client recently asked me to implement a slideshow on our website. I'm concerned that constantly animating picture transitions on the homepage will peg the processor of most mobile devices, so I want to disable the automatic advancing to preserve battery life. Is there any way to do this without trying to detect the user agent?
I've seen that there is a battery status API drafted here, but I don't know how complete it is, or which browsers have implemented it.
Actually determining battery would be quite difficult and probably involve various permissions problems.
Try just executing a small piece of code and checking the time it took. Pick a cutoff and if the code executes too slowly, turn off the transitions/animation/autoadvance. This will catch more than just battery devices; anything too slow will get the un-animated version. Degrade gracefully.
Now you can, with this API: http://davidwalsh.name/javascript-battery-api
navigator.getBattery().then(function(result) {});
Another old topic, but still relevant - I now check if the device has motion sensors, not many laptops do, but all modern smart phones and tablets do - so laptop users can live with slightly more battery use -
jQuery:
if (window.DeviceOrientationEvent) {
$(window).one("devicemotion", function(event) {
if (event.originalEvent.acceleration
&& event.originalEvent.acceleration.x !== null) { // Chrome fakes it on desktop
isMobile = true;
}
});
}
Plain Javascript:
if (window.DeviceOrientationEvent) {
window.ondevicemotion = function(event) {
if (event.acceleration
&& event.acceleration.x !== null) { // Chrome fakes it on desktop
window.ondevicemotion = null;
isMobile = true;
}
};
}
code:
google.load("earth", "1");
function gemap_init()
{
google.earth.createInstance('gemap', initCB, failureCB);
}
function initCB(instance)
{
try {
ge = instance;
ge.getWindow().setVisibility(true);
console.log(ge.getPluginVersion());
google.earth.fetchKml(ge,
'http://example.com.au/maps/example.kml',
function (kmlObject) {
if (kmlObject) {
ge.getFeatures().appendChild(kmlObject);
}
if (kmlObject.getAbstractView() !== null) {
ge.getView().setAbstractView(kmlObject.getAbstractView());
}
}
);
} catch (e) {
console.log(e);
}
}
function failureCB(errorCode)
{
alert(errorCode);
}
google.setOnLoadCallback(gemap_init);
for some reason this is working in every browser on my PC - but when I test on random computers and browsers around the office it is failing to display the markers or move the camera from the kml.
operating systems and browsers range from XP to Vista, and using FF, Chrome, IE7, IE8 - there is no pattern to the failure.
failing plugins are the same version as working plugins.
this is becoming a hair-pulling event for me as i just can't see where the fail is.
EDIT:
just to make clear - it is working in all those browsers and all those OSs - but not always, and not consistently...
there is no change in the javascript or kml between it working and not working.
the kml is a valid document
all browsers report that they are using the same plugin version
The comment from Fraser has reminded that this question was left open...
We have resolved the problem by appending a unique ID which is regenerated whenever the KML data on the server is updated.
This seems to bust the GE cache and we no longer have any problems with missing or out of date data being loaded in the plugin.