Hi I'm new to Apache Cordova. I've recently developed a web application that works fine on chrome and devices but when i get Visual Studio Apache Cordova (visual studio 2015) output some CSS files seem to be not loaded completely i mean some parts of CSS are not working as it must. and the second problem is the output is different in different devices on nexus 5 it is 90% OK but in LG L70 or bluestacks less than 30% is OK.
anyone knows the reason and solution?
Thanks
Well, without any code it is hard to tell (and your question is very broad!). I also have to bite my tongue in order to not go raging against Cordova (again).
But from my (luckily) poor experience with Cordova you have do deal with different WebViews and their different implementations.
I recommend you to get the Android WebView version of your device and test your app with this in mind. May you find similarities like "Everything goes wrong in WebView versions below 3.2.1" and modify your app accordingly to your findings.
First make sure you don't have any errors in your html / css by using the online validators.
Second, make sure the CSS you are using is available on the version of Chrome / Android that those devices have (www.caniuse.com). Make sure you are using the browser specific prefixes where needed (i.e new versions of Chrome would not need, but older Chrome/Webview would).
In my experience that will find many of the issues with a Cordova app, especially on Android. Most likely your CSS is not taking into consideration all the variation among mobile browsers. It is not easy to do unless you have done it before.
Another way to ease these issues on Android is to use the Crosswalk plugin. Since you are using VS 2015 it is real easy and available in the config.xml editor to add. This will increase build time / size of the app, but it is just about necessary for serious Android hybrid app development. What crosswalk does is package a new up to date version of Chromium with your app. It makes many issues like you are seeing go away, plus it gives you a lot of newer web APIs (webrtc for example) on the devices.
One last option is to use a tested / supported library like ionic (can just use their CSS if you want and not full stack), jQuery mobile, Onseen UI, etc... You can use this together with Crosswalk to get a very consistent experience on all the Android devices / versions.
Related
When writing CSS and JS for Cordova apps, how do I figure out which features are available to use? When I go to caniuse.com, am I looking at iOS Safari and Android Browser or Chrome? Is there a table somewhere that will help me map Cordova versions, OS versions, and browser versions?
I've been stung once by the JS await operator not working in an app that I thought would work in iOS 10.1. I'm now not sure how to tell what's the oldest Android version on which that app will work. And I'd like to be able to figure out which features are usable based on an OS decision predetermined by my clients or managers.
This is a very good question and one that cannot be answered with a single sentence. I can share some experience though:
Android vs. IOS
IOS is the most predictable as all Apps have to use the same WebView that comes with the OS. When you set a minimum IOS version (for example 10.0) you can look up supported features for Mobile Safari on caniuse.com.
Android is a completely different story as there is absolutely no way to predict which WebView the user is using. It will usually be some version of Chromium but starting from Android 5 it can be updated independent from the OS via the Play store. If you absolutely must support Android 4 you could create a separate build and using Crosswalk (unmaintained but still working) to get a predictable WebView.
JavaScript / CSS
If you're using Ionic then JS will usually be less of a headache as you develop in TypeScript and transpile to ES5. For CSS on the other hand you will have to resort to the usual browser checks / hacks / fallbacks as we did back in the days when we had to deal with browsers like IE6.
I am making an application which gives support to webRTC for android & ios both for this I make a lot of R&D then I found an Ionic framework to support both platforms. you can see here/ionic. no doubt it is a powerful tool for us in nowadays. and for supporting webRTC I have used crosswalk. because internally ionic use phone`s browser means for android it uses Chrome and for ios ,safari but the issue was there: older version of Chrome did not support for webRTC and safari did not till now. so with crosswalk webView all thing is working fine means calls are getting connecting and user A and B can communicate utterly but I am facing an issue of apk size which is also mentioned # crosswalk issues tracker. I have done all possible ways to reduce the size of apk which is mentioned there - by generation two apks , but apk size is still more than 25 mb.
I found another way was to disable all instead of WebRTC -but I am not sure ,will it works or not / how to do that?
so can you please let me know how to solve this issue with the crosswalk. or is it possible or not ? if it is then how can I do this else please give me some references of plugins(webVisew) which supports webRTC.
thanks in advace.your help can save me thanks.
Yesterday I tried using Phonegap with a web app that uses angularjs and angular material. The performance is very slow on my device (ASUS Zenfone 5 running 5.0) including the animations and keyboard input which takes about a second before a character shows when typing. I've researched about Phonegap's performance and some says that I should try to use Crosswalk Project but still, the performance isn't good.
To my curiosity, I built an android app which uses the Android native WebView that uses WebChromeClient and the performance is better than a Phonegap + Crosswalk, but why? Isn't Phonegap also uses the Android native WebView then just load the site as an asset?
As far as I know, Phonegap/Cordova use the Chrome webview. By using Crosswalk, you ensure that you always use the latest Chrome webview, independent of what Chrome version is actually installed on your phone.
It could (but I think it's unlikely) lead to a difference in performance. What I expect however, is that some Cordova plugin you loaded is the culprit. I've seen (and read about) plugins that just drop the performance of your whole app.
EDIT:
I've only done one experiment with Angular Material myself, and I wasn't experiencing any real performance issues at the time, but I did read some people writing about it being slower than plain Ionic.
My suggestion would be to try to build an Ionic app (it's just plain Angular with performance optimizations and some handy directives). If you want to have Material Design for it, you can try Ionic Material. I made the switch to that, because I found some very hard to track issues with Angular Material, and it didn't follow the Ionic way of doing things.
Ionic Material has to easy to access documentation yet, but their Demo is full of code examples
In my team we are developing an application which is going to be played on tablets, the project has been largely developed and tested on Google Chrome.
At this time we are inserting this webapp on Apache Cordova in order to display it as a native application on Android (and later on iOS), but the app doesn't displays well on the tablet, this because of the WebKit version, which varies on every Android version and does not work as in Chrome.
The question is... There is any way to change the webkit version which operates with Apache Cordova? (or any other web rendering engine)
There is no way at this current time to change the Webkit version used by Apache Cordova - this is because Cordova uses the native Android WebView component, which is based on an old Webkit version. The native Android WebView is quickly becoming the IE 6 of the mobile world, if it isn't already.
EDIT WHOOO! Android 4.4 announced that the default WebView will now be built on top of Chromium! This means that Cordova apps running on Android 4.4 should run much faster (new JS engine) and support more features (HTML5 things.) There is still a lot of confusion around this new WebView and what it means. The best article I have read so far is here: http://www.mobilexweb.com/blog/android-4-4-kitkat-browser-chrome-webview
A lot of people have realized that this is becoming a big problem with Cordova apps. There has been some experimental work to build a version of WebView that uses the Chromium source (and thus an updated version of Webkit (Blink?)), you can view the code here: https://github.com/pwnall/chromeview Check out the "issues" tab and follow it; I've been getting a few emails every week from people filing issues. I think some forks are ahead of others and hopefully they are getting close. (According to Cordova mailing list archives, Opera was able to get this working on 2.2 but I can't find any code or anything more than a passing reference.)
If you are able to get WebView built with Chromium, it shouldn't be that difficult to switch out which WebView class Cordova uses; I'm pretty sure this ability was already added to Cordova with this and similar commits: https://git-wip-us.apache.org/repos/asf?p=cordova-android.git;a=commit;h=f6049881
I think a lot of people are holding their breath that Android 5.0 will finally have an updated WebView that uses Chromium source and will be updated in sync with Chromium... if so, that'll be awesome, but it still leaves us with 4.0 and below that doesn't seem to work at all.
I'd suggest checking out CrossWalk. It's developed by Intel and uses the Blink rendering engine (same as chrome). You package it with your cordova app and then you can use same the Web rendering engine across all devices and versions 4.0+.
https://crosswalk-project.org/
Note: It adds about 20MB to your app's size, but I'd say that's minor for the headaches it would save you in cross device/version testing that you'd have to do.
Check out here to get started with crosswalk and cordova..
https://github.com/crosswalk-project/crosswalk-website/wiki/Create-Sample-App-With-Crosswalk-Cordova-Android
With the release of Apache Cordova Android 4.0.0, it supports "pluggable WebViews".
So, using Crosswalk with Cordova is just matter of installing the cordova-plugin-crosswalk-webview.
For our Android app, we would like to embed our own browser/rendering engine. The most likely candidate for this, is Webkit/Chromium. We are looking for something similar to WebView, essentially, but backed by a browser (version) that we control.
Background
Significant parts of our app consist of web page fragments embedded in the view (served by the app itself). We try to do this as transparently as possible (from a visual/user experience standpoint). So far, we have been using WebView for this and that works for the most part. Except when it doesn't.
Some phone vendors have unfortunately decided to tweak the standard Android browser here and there. In some cases, this breaks our app or makes the fact the we embed a web page more noticeable.
Our Idea
We'd like to have a component similar to WebView but where we control what version of Webkit/Chromium (or some other rendering engine) is being used. It wouldn't necessarily have to be the latest and greatest version. It is more important that we can get our app to work consistently across as many Android devices as possible.
So far
Our research so far has not turned up anything useful. We have found three dead attempts to port Webkit to NDK (the bare Webkit for Android port uses functionality not available in the NDK and thus not to app developers):
Webkit Android port by Company 100 (no updates for over two years)
mogo-browser (their last revision was to delete all source code)
NDK Webkit (officially abandoned by its author)
Looking on StackOverflow, we have also found a number of similar questions, most of which being solved by pointing to WebView (we already do that, and it's not good enough)
Webkit component for Android
Embed basic WebKit + V8 in my app
Embedding a newer version of WebKit with Android app
We are currently investigating whether Chromium for Android (or parts of it) can be turned into a library that our app could use. Has anyone else done this?
Update
After having a look at the chromeview project on GitHub (accepted answer), we decided that we'd rather wait for Google to release a Chrome-based WebView on future Android devices. The Chromium rendering engine turns out to be fairly large (~40MB), which doesn't leave much space for the actual app :(
pwnall/chromeview ยท GitHub
https://github.com/pwnall/chromeview
ChromeView works like Android's WebView, but is backed by the latest Chromium code.
You should all check out the Crosswalk project. Sponsored by Intel, and in active development. They pull the Chromium sources and promise to make all new Chromium features available in Crosswalk within 6 weeks.
Crosswalk is a web runtime for ambitious HTML5 applications. It provides all the features of a modern browser, combined with deep device integration and an API for adding native extensions. It is especially suited to mobile devices.
Crosswalk supports Android 4.0 and newer, on ARM and Intel architectures.
Within in one hour of finding this project, I had my Cordova/Phonegap app running on an Android phone with Crosswalk. I'm glad I don't have to adjust my Javascript code to respect the shortcomings of the (pre-4.4) android.webkit.WebView.
https://crosswalk-project.org
Without WebKit there is a GeckoView. Sure it adds over 20Mb of libs to the project.
Nowadays, GeckoView seems an alternative to consider
I tried to use lastest code version of Chromium to build a custom WebView and it's successful.
I will give my approach but not the source code here right now.
Eventually, the size of custom WebView library is about 30MB, quite big for some small app. But it's wonderful because can support perfectly from Android 4.0.
This below is my method:
fetch source code of chromium and build web_view_apk (AndroidWebView test shell) follow this instruction https://www.chromium.org/developers/how-tos/android-build-instructions
use apktool to decompile the apk file of Aw Shell above. https://ibotpeaches.github.io/Apktool/
create your project with res, lib folder as same as decompiled project.
Manifest file is located in /src/android_webview/test/src/org/chromium/shell
src folder: you find the classes in chromium project source code which are respective the files in smali folder of decompiled project.
I will update my code later, but you can try my guide now if don't want to wait.
I would consider Chrome custom tabs:
https://developer.chrome.com/multidevice/android/customtabs