How do I enable the debug view like I can in Safari on iOS? I simply need to see if a Xoom that I'm testing a page on is generating javascript errors. I was trying to find how to enable the dev tools in the Android browser like I do for iOS but can't seem to locate it.
I've worked on an Android app in the past where the java developer set it to alert JavaScript errors - caught an extra bug that we didn't catch in the iOS version because of it. So, if you have access to the java layer, I'd check that out. I asked him what he did specifically and he said:
"There's a callback from the WebView class that lets me know when the JS code throws an error. I implemented that callback to display an android dialog."
There's two solutions other ideas on top of this that I use for debugging (ios/android). These are especially useful for embedded web views in games where you don't have access to the built-in console:
1) Weinre a still beta, but functional, remote debugger. It'll give you a faux inspector on your desktop that you can query / see errors on your remote device with. Has a whole dom inspector and anything. The guy that develops it is pretty responsive, too.
2) I write a javascript log function that hits my servers error log. Just tail your log file and you're good to go. My javascript function looks something like this:
function hlog(){
var s = Array.prototype.slice.apply(arguments).join('¶');
document.createElement('img').src = 'http://yourdevbox/debugger/?m=' + encodeURIComponent(s);
}
That way I can take any number of arguments.
My php page that recieves this request looks like this:
# ensure this can't be used in production
if (strpos($GLOBALS['HTTP_HOST'], 'devboxhostname') < 0) die(':(');
error_log($_GET['m']);
Hopefully in the future, mobile devs will have way better debugging tools.
Android doesn't (currently) have a WebInspector like Chrome/Chromium does.
You can still look at any console.log() messages fired under window.console in logcat.
Source: http://developer.android.com/guide/webapps/debugging.html
Also, whilst Firefox 4 is available for Android, Firebug currently isn't supported on the mobile version of the browser.
type about:debug into the url field and validate, a javascript console will then be available (same method to remove it)
a bit more on this page: https://android.stackexchange.com/questions/5999/android-browsers-aboutdebug-what-do-those-settings-do
The best you can do is use console.log() (like firebug), and then install a log viewer on your phone, filter based on browser, and you can see all the console messages. (source)
Try
Weinre: Web Inspector Remote / Watch demo
"Weinre is a debugger for web pages, like FireBug (for FireFox) and Web Inspector (for WebKit-based browsers), except it's designed to work remotely, and in particular, to allow you debug web pages on a mobile device such as a phone. "
You may have a look some other remote debugging tools: jsconsole or
Aardwolf
Opera mobile has remote debugging:
http://dev.opera.com/articles/view/remote-debugging-with-opera-dragonfly/
The Android default doesn't seem to have a debugger, although you can debug on chrome/chromium on a pc, which uses the same webkit rendering. (There's even a emulate Android option, but it doesn't have all the quirks of Android tablets, image/memory constraints etc.)
Firebug Lite is also a possibility:
http://getfirebug.com/firebuglite
You don't have to install any software or try to debug in your tiny mobile screen.
First enable USB debugging in your device in the "Developer settings" and then use your desktop chrome to connect and debug the mobile browser.
I found the easiest way is to enabled USB debugging on the phone/tablet and in your desktop navigate chrome to
chrome://inspect/#devices
Enable discover usb devices and then on the list of apps click "Inspect"
Voila! Remote debugging! Now you can debug your phone from the comfort of your desktop
Related
An AngularJS application works fine on desktop, but is not rendering properly on mobile (actual code is showing). This is on an Android phone.
I would like to see what errors are showing in the console.
Is it possible to open JS console on chrome app on mobile (like it is on desktop)?
You can do it using remote debugging, here is official documentation. Basic process:
Connect your android device
Select your device: More tools > Inspect devices* from dev tools on pc/mac.
Authorize on your mobile.
Happy debugging!!
* This is now "Remote devices".
When you don't have a PC on hand, you could use Eruda, which is devtools for mobile browsers https://github.com/liriliri/eruda
It is provided as embeddable javascript and also a bookmarklet (pasting bookmarklet in chrome removes the javascript: prefix, so you have to type it yourself)
To use remote debugging first activate developer mode in Android.
In Android go to Settings, search build number, then click on it several times to activate developer mode
In Android go to Settings > Developer Options > Enable usb debugging
Connect to computer with usb cable
In desktop Chrome type chrome://inspect , then press enter
In mobile open url then check it, on this page on desktop chrome://inspect/#devices
The original answer doesn't seem to be valid anymore. From the current Chrome developer docs, these are the basic steps you need to go through:
Open the Developer Options screen on your Android. See Configure On-Device Developer Options.
Select Enable USB Debugging.
On your development machine, open Chrome.
Go to chrome://inspect#devices.
Make sure that the Discover USB devices checkbox is enabled.
After that, open Chrome on your Android device (and confirm the USB Debugging prompt in case it pops up). Switch back to your PC and you should see the currently open browser tabs:
If your device tabs do not appear, you might need to trigger the USB Debugging prompt by activating file transfer on your mobile device.
Kiwi Browser is mobile Chromium and allows installing extensions. Install Kiwi and then install "Mini JS console" Chrome extension(just search in Google and install from Chrome extensions website, uBlock also works ;). It will become available in Kiwi menu at the bottom and will show the console output for the current page.
Edit 2022:
It's even better now. The console is built-in and available in the menu.
Please do yourself a favor and just hit the easy button:
download Web Inspector (Open Source) from the Play store.
A CAVEAT: ATTOW, console output does not accept rest params! I.e. if you have something like this:
console.log('one', 'two', 'three');
you will only see
one
logged to the console. You'll need to manually wrap the params in an Array and join, like so:
console.log([ 'one', 'two', 'three' ].join(' '));
to see the expected output.
But the app is open source! A patch may be imminent! The patcher could even be you!
I you only want to see what was printed in the console you could simple add the "printed" part somewhere in your HTML so it will appear in on the webpage. You could do it for yourself, but there is a javascript file that does this for you. You can read about it here:
http://www.hnldesign.nl/work/code/mobileconsole-javascript-console-for-mobile-devices/
The code is available from Github; you can download it and paste it into a javascipt file and add it in to your HTML
The Kiwi browser not only allows you to use Chrome dev tools but you can also view the page at the same time.
If you use Android split screen you can open a window and move the dev tools to a new window.
Use Kiwi Browser app
Allows you to install all chrome extensions as well as access dev tools (console, ...)
Or
to access and test all the consoles of different mobile browsers, you can use the following similar websites:
https://www.browserstack.com/
Remotely debugging Firefox is another option. the steps are mentioned here
I am currently working on a HTML/JS application that will be embedded in an iOS and an Android app. Because the android app is not yet finished I am testing this on the chrome browser in Android. I fixed all issues there but when I open the same web app in the native browser nothing really works as expected.
So my question is : Is there a way to debug in a native browser on an android device?
In chrome this was pretty easy with remote debugging.
(Please do not advice me to use 'log' statements for debugging because that's not what I am looking for here)
And just to spill my guts : the Samsung Tablet's native browser is the only device that's causing me a headache!
Typing about:debug in the address bar of the native browser will toggle the 'Debug' options in the settings menu.
The 'Show JavaScript Console' option will allow you to see JavaScript errors in your webpage.
NB I believe the JavaScript Console will only be displayed if there is an error.
HTH
Nick.
The new Samsung Internet browser (I think you meant this browser with "Samsung Tablet's native browser") is now based on the Chromium browser and thus supports its remote debugging interface.
Enable USB debugging on your device as described here.
Then connect your device via USB (Oh, surprise!).
Visit chrome://inspect on your computers Google Chrome browser and you will be guided to create the connection:
Then you just have to click on the devices inspect link and an developer tools window will pop up.
More info like why there is an Samsung Internet Browser at all can be found here.
You can easily debug your web application with Web Inspector Remote (weinre).
Look at this post in order to find out how to install and use weinre.
I hope it will help you if this question is still actual.
If you have updated your device you can go to settings -> Debug -> 'Remote Debug Enable'
Once enabled you can debug the native browser just like you can debug chrome.
You can try vorlon solution too, it has a nice web interface & very easy to install
& It's free
But if you can't see clear console errors with volron, you probably want to use #Nick's solution, sometimes complex errors prevents even vorlon or weiner from catching them. So once you fix blocking these issues, probably volron will start catching them properly
I have an iPad and I am wondering if I can remote debug it from the desktop using Webkit Inspector? As I understand it, it requires you to launch the browser with a command line switch. I do not think that's possible to do in iPad, but I may be wrong.
What about iPad2? Or Android powered tablets?
See weinre
Here's an excerpt:
It's a debugger for web pages, like FireBug (for FireFox) and Web Inspector (for WebKit-based browsers), except it's designed to work remotely, and in particular, to allow you debug web pages on a mobile device such as a phone.
If you aren't familiar with FireBug or Web Inspector, weinre isn't going to make too much sense to you. weinre reuses the user interface code from the Web Inspector project at WebKit, so if you've used Safari's Web Inspector or Chrome's Developer Tools, weinre will be very familiar.
Now you can debug using Safari 6 and the new Web Inspector straight on the iPad/iPhone simulator http://encoreptl.tumblr.com/post/31512516711/web-inspector-debugging-for-iphone-and-ipad-from-mac-os
Also a new blog post out using private apis that makes this very easy -- see http://atnan.com/blog/2011/11/17/enabling-remote-debugging-via-private-apis-in-mobile-safari/
For the iPad Emulator (Xcode 4.2) you can use iWebInspector to comfortably enable the remote console:
http://www.iwebinspector.com/
Your question mentions Android tablets. With Chrome for Android (4.0), you can debug web pages remotely in Chrome for the desktop over USB. I use this and it works very well. See https://play.google.com/store/apps/details?id=com.android.chrome&hl=en and https://developers.google.com/chrome/mobile/docs/debugging.
Edit: weinre, mentioned in the accepted answer above, also reports that it works in the Android browser.
Paul is correct, weinre is great. In addition, in http://css-tricks.com/14727-five-questions-with-paul-irish/ Paul Irish hints that this will be (is?) possible with the Chrome Developer Tools/Webkit Inspector:
I'm very excited about the work the team has done on remote debugging as that is now available to all mobile WebKit ports, which means you're able to profile, view network detail, and edit the CSS live on your device.
I have yet to see an example on how to do this with iOS Safari, however.
You can also use this to activate Firebug on your device. Worked for me on Windows
http://martinkool.com/post/13629963755/firebug-on-ipad-and-iphone
Safari allows you to debug and inspect the elements in the mobile browser. Also many remote consoles like www.farjs.com or jsconsole.com also allow that.
www.farjs.com used with a debugging proxy like Charles also allows you to debug a web-views in native apps.
If you are not tied in to Webkit-based debuggers and can also debug using Firefox's Inspector, using Firefox Developer Edition might be your answer.
This version of Firefox includes WebIDE and Valence, which together make it very easy to debug Safari on iPad. Here are the steps to follow:
Enable the 'Web Inspector' on Safari in your iPad: go to Settings > Safari > Advanced > Web Inspector and make sure it's on.
Open the page that you want to debug.
Connect the iPad to your machine with its USB cable.
Open Firefox Developer Edition in your machine.
Click on the WebIDE add-on in Firefox (you might have to look for it under the main menu)
Select 'Safari on iOS' as the Runtime
Click on 'Open App' and you'll see the page that you opened on Safari listed there.
Select it. A FF dev tools window will appear.
Debug away!
I want to debug my PhoneGap app in Xcode, but its Console can not show javascript errors.
The most elegant way to view and debug JavaScript errors in your Cordova/PhoneGap App is by attaching the Web Inspector from your Safari browser to the Web View in your iOS App (but, like Tom Clarkson already mentioned, you will need at least iOS 6).
On your iPad or iPhone use the Settings App to enable Web Inspector in the Advanced Settings for Safari
Connect your device to a Mac via USB (it will then appear under the Develop menu of Safari)
Start your App
Navigate to the Web View you want to debug
On the Mac, from the Safari Develop menu, select the name of your device and the App (its HTML-page), from its sub menu
A Web Inspector window will open, enabling you to browse the DOM, set breakpoints etc.
Apples documentation on setting this up
A thorough third party tutorial
Alternatively you could connect Chrome’s Web Inspector to iOS devices after installing iOS WebKit Debug Proxy. This also opens up the ability to do the inspection from Linux or Windows.
Remote access to your iOS’s HTML, CSS and JavaScript has gotten even more flexible nowadays because you can install the RemoteDebug iOS WebKit Adapter on top of aforementioned Debug Proxy. Because this adapter translates the WebKit Remote Debugging Protocol to the Chrome Debugging Protocol, these (on all their supported platforms) become available as alternative debugging and inspection tools:
Visual Studio Code
Chrome DevTools
Mozilla Debugger
BTW, remote debugging with the Safari Web Inspector works even in combination with the iOS Simulator.
Minimum version of Desktop Safari per iOS version
For each version of iOS you will need a specific minimum version of Desktop Safari in order to use remote web inspection, see the list below.
iOS 6
Safari 6+
iOS 7
Safari 6.1+
iOS 8
Safari 7.1+
iOS 9
Safari 8+
iOS 10
Safari 9+/10+? Please comment; always try Safari Technology Preview
iOS 11
Safari 11+
iOS 12
Safari 12+
Paste the following somewhere near the start of your document so that it gets executed before any of your other JavaScript.
<script type="text/javascript">
window.onerror = function(message, url, lineNumber) {
console.log("Error: "+message+" in "+url+" at line "+lineNumber);
}
</script>
And enjoy viewing details of your Javascript errors in the Xcode console window.
UPDATE: The above technique will log errors such as undefined variables. But syntax errors such as missing commas will still cause the entire script to break without logging anything.
Therefore you should add the following to the start of your onDeviceReady function:
console.log('Javascript OK');
If you don't see "JavaScript OK" appearing in your log window when the app launches, then it means you have a syntax error somewhere.
To save hunting for missing commas, the easiest thing is to paste your code into a Javascript validator such as this one:
http://www.javascriptlint.com/online_lint.php
and let it find the error for you.
Hopefully that takes some of the pain out of debugging.
Note that with 0.9.2 (released today), console.log has been standardized across the platforms for logging (with debug.log deprecated).
There is a function that is available on the desktop WebView that is not exposed in the iOS UIWebView that will catch all errors (I'm trying to hack that functionality into a plugin, which uses private APIs, but the plugin would only be for development), but for now do what Kris suggested above and put try catch blocks on code and use console.log
To quickly catch possible syntax errors, when developing I have the page loaded in desktop Safari and quickly refresh it with the webkit error console viewable.
debug.log will send messages to the XCode console in Phonegap (allowing you to either log the result of an exception or do some debugging), however, you are correct that you have to debug other javascript errors in Safari (either on the desktop or on the iphone with Debug Console turned on). I have yet to find a Javascript error, that was caused by running on the iphone and wasn't present when debugging with the console turned on in Safari (though I know there are a few differences between the WebView and Safari on the iphone).
I just came across Weinre
It's a remote javascript debugger for phonegap. You can either setup your own Weinre server, or use the one at http://debug.phonegap.com/
It seems to work well - very impressed so far.
If you use iOS 6, you can simply attach the safari web inspector (on the develop menu of desktop safari) to your app and get full javascript debugging.
There are a couple of areas where it is a bit limited - startup errors and plugin calls - but it works well for pretty much anything else.
For making javascript debugging work in Xcode I would take a look at the following.
http://phonegap.com/2011/05/18/debugging-phonegap-javascript/
http://www.daveoncode.com/2010/01/12/debugging-phonegap-applications-using-xcode-console/
As as far as additional troubleshooting goes...
To start with you could run the app in safari on you pc and utilize safari's debugger (or chrome as both are running similar rendering engines). This won't hit on the advanced logic errors and many of your api issues but it at the very least should help with troubleshooting many issues (basic javascript, HTML5 etc....).
To view all errors in javascript console, I agree to use this event listener
<script type="text/javascript">
window.onerror = function(err,fn,ln) {alert("ERROR:" + err + ", " + fn + ":" + ln );};
var errorVar = objectDoesntExists.properyDoesntExist;//this will simulate an error
</script>
However, unless you have the cordova plugin installed, it wont show on XCodes "console". Go to your project folder and type this:
? cordova plugin add cordova-plugin-console
This will allow the javascript command 'console.log('some string') to show on XCode.
Note you will need git, etc... but if you are editing your phonegap project in xcode, you will most probably have it!
PS Make sure you put the cordova.js script plug-in before any use of console.log
<script type="text/javascript" src="/cordova.js"></script>
Put this in the beginning of your index.html
<script type="text/javascript">
window.onerror = function(err,fn,ln) {alert("ERROR:" + err + ", " + fn + ":" + ln);};
var errorVar = objectDoesntExists.properyDoesntExist;//this will simulate an error
</script>
Here's a simple way that worked for me:
cd to the directory containing your index.html file in the terminal
Start a http server using python by invoking (I used python 2.7):
python -m SimpleHTTPServer
View the page in safari by entering the address of the HTTPServer in a browser, for me the URL was:
http://0.0.0.0:8000/
Open developer tools:
In chrome this is alt+command+i. View the console tab, may need to refresh the page.
In Safari: Safari --> Preferences --> Advanced --> check "Show Develop Menu". Develop menu --> Show error console (or alt+command+c). Refresh the page. Hitting CTRL+5 opens the issues tab.
I'm developing a JavaScript application that needs to run on the Google Android Phone OS. Is there a way to enable the JavaScript Error/Debug console within Safari on either the Android Emulator or an actual device? If so any instructions on how to do so would be appreciated.
It looks like, with the Android 2.0.1 SDK you'll need to filter on "browser" instead of "WebCore"
A quick Google turns up this blog post (posted after you asked your question), that should at least let you see any Javascript errors via the Android Debug Bridge using the command:
adb logcat WebCore:V *:S
Not quite the same as a full debug console though.
On Android write about:debug on the address line when the current page is the page you want to debug. you will get access to the console.
I know your question is about Safari, but you might want to look into using Chrome instead. You can now use Chrome's desktop developer tools to debug and profile apps on your Android device.
Here's how:
On Android Chrome, go to settings -> Developer tools and check "Enable USB Web debugging"
On the desktop, run adb forward tcp:9222 localabstract:chrome_devtools_remote
Now on Desktop Chrome, navigate to localhost:9222.
You should see a list of the pages you have open on your phone. Click the one you want to debug/profile.
Detailed instructions are here
I have discovered that you can get this debugging information on the phone itself, without needingn to use adb or plug it into a computer, just download a log viewer.
Check the link for more info.
You can view the log and much more with weinre
From the Weinre docs
weinre is a debugger for web pages, like FireBug (for FireFox) and Web Inspector (for WebKit-based browsers), except it's designed to work remotely, and in particular, to allow you debug web pages on a mobile device such as a phone.