I have a given Javascript browser application with login screen and data display screen. It does request JSON data via calls that are always the same (i.e. http://myserver.lol/api/getData?mobile), the data changing only slightly over time.
What I want is a mobile app for Android/iOS/Windows Phone/Blackberry, which
-> at best "caches" the whole web site (html/js...) in the app, so I don't have to rebuild the app whenever the web app changes;
-> provides some form of "auto-login"/"auto-form-fill", so the user does not have to give his credentials every time, and
-> some kind of long-term cache for the JSON data, so it is requested from server when a fast network connection (LTE/WLAN) is available, but taken from Cache on GSM or without connection.
Which Framework would allow to implement this the easiest? I am just now looking at the PhoneGap docs and the Titanium docs, but I guess I am overlooking something, or don't they provide an easy solution for this? Or perhaps you have an insider tip for me on another framework?
You can definitely handle this buy using both frameworks. I use only Phonegap / Cordova.
I would do this all by building the application with Phonegap together with AngularJS.
You can use templates in there, so you don't have to fetch the Ui from your server.
To cache data (user credentials or JSON data) I would just use the localStorage which is available on all devices (see here).
I recommend angularJS because it is a really great framework which helps you build Web-Applications really fast (but if you already have an existing application this might not be an option for you).
I hope this helps ;-)
Related
I know that the most Iconic feature of PWA are
Service Worker: which make user can use the app offline from cached resources
Add To Home Screen: With this feature, user can add a shortcut of the app on their mobile home screen, to get a experience like interacting with a Native App(But there still a huge different, in my opinion)
etc.
However, I can do like all of them on about 6/7 years ago by using the HTML5 technology at that time, I know that service worker comes recently but there also was "HTML5 App Cache, as well as the Local Storage, Indexed DB, and the File API specifications." can do similar things.
Is there anyone can explain what's the difference between PWA and HTML5 webapps? or they are just the in term of same? or a similar concept but different implementation? or PWA is the (next gen/extension) of HTML5 webapp?
I might have some misunderstanding on PWAs, since I am new to this term, Thanks.
If keep it simple PWA is ordinary site with 3 additional features.
responsive design - site should look well on all devices
manifest.json - site must have general description about itself stored in manifest.json
caching - site must work offline
I believe 1 and 2 is easey. And 3 is realy what PWA is all about. So the question is: how we can provide offline support?
First problem is how we can get our initial .html .css and .js files without internet connection? Answer is: we should use service worker or App Cache. But App Cache has a lot of problems and probably will be deprecated, in other hand service worker under developement and become better each month. You can read more about their difference here.
Second problem is how we can get server data without internet connection? We should store most vital data somwhere. But after we get our .js file from cache we have access to Local Storage, Indexed DB etc. So we can store vital data in any of this storage while we online and get it back from them when we offline. It is totally up to you how you will handle that.
I believe there no cleare and strict defentiton for PWA and HTML5 webapp (at least for now). So you can asume it is the same but today PWA is more common word.
Imagine a social network application similar to twitter which every user is following and is also followed by some other users and whenever a user sends a message (text or photo) it is displayed instantly on the screen of users following him/her. What is the best way to make such an application for:
mobile
web
I have some web programming experience and the only way I know to do this in web is to send an ajax call every second from a user's client. My feeling tells me there should be a better way. I did some research and found webrtc. Is that the way to go? I (and probably many other users) will be grateful if you can explain the pros and cons of the solution you suggest.
Thanks a lot.
If you want to build conference app/ messaging app for web/mobile platform you can use latest web technologies.
Node.js is an Javascript framework which does efficient and non blocking IO and it works really well with applications which are not data intesive which involve lot of calculations.
Please go through Node.js and libraries associated with it, you can ahieve building efficient chat application.
I created a scheduling software for beauty salons as a web application. The idea is that the business owner can schedule customer appointments with a hair stylist. I made it web based because eventually these beauty salons need to integrated into a larger cloud service. So far, I've only put in about 40 hours of coding.
One challenge i am encountering is that a lot of beauty salons may have poor internet connectivity. They may experience temporary outage that last several hours to several days. But during this time, they still want access to this web application .. at the very least for read only purposes.
I understand that html 5 in modern browsers support offline capabilities via things like localStorage and cache manifest. It appears to me that at the moment, I need to do a drastic rewrite of my existing application to make use of localStorage and cache manifest to allow the web application to work offline. The reason this is so is because my web application writes/saves a lot of information to urls like http://mywebsite.com/api/somefunction?queryparams=value1 via ajax calls. These ajax calls need to be replaced by function calls that write to localstorage.
So my questions are:
a) To enable my web application to work offline (at the very least, read only of the website should be offline), I should replace my ajax calls with calls to localStorage. Is this the best approach?
b) Would it have been better to create this application as a .NET desktop application? Especially if there are microsoft technologies that help with synchronizing stored client data with an external database at a later time?
My opinion:
a) I wouldn't say you should replace your Ajax calls. Rather, you want your code to notice when it is offline and store stuff in localStorage then. You wouldn't always store in localStorage as your clients are going to be online sometimes.
b) That's kind of a loaded question I think. :) So... my thinking is this: Building a web site makes sense as it would let your clients at the salon access their data both from computers in the store and other devices as well. So for example - if the salon's internet access is down, the employees could perhaps use your website via their mobile phones too. Having the data be web bound gives them more ways to get to it.
So this is more of a general question about apps and techniques rather than a specific code question...
When developing an larger app, how would a developer access lots of data from a website. The example I'll use is an app like Yelp. They have both a web-access site and an app, both share the same information. I would imagine that information like that is stored on the website via some sort of MySQL database and the iOS device access's it as needed based on the user's requests.
How might a developer writing an app start something like this? I assume you need to somehow securely tie the MySQL database to iOS and so on. I've seen a lot of techniques on the web, but they all seem very simple and not safe for a large scale app.
Any ideas would be awesome!
The key term you're looking for is "API" (Application Programming Interface).
A Yelp iOS app won't access Yelp's databases directly. There will be a layer (I simplify here somewhat) between that and the iOS app; this layer will provide a series of methods (the API) by which clients can make queries and potentially manipulate remote state.
A common API format is JSON over HTTP, and indeed, this is what the official Yelp API seems to be.
Good starting points would be the documentation for NSURLConnection and NSJSONSerialization, and the Yelp API documentation I link above.
I want to design a website but I don't know from where to start.
Is there a beginners' guide to start with?
How much dedication do you hope to provide? If you merely want to design a single website, quickly and dirty, there's a plethora of open source web templates available online, with clean and basic HTML/XHTML design strategies that you could modify, and provide content for.
Such as this and that.
Alternatively, if you would like to design your own websites from scratch and have full technical knowledge in the field (the proper way). Pick up a book or two on HTML/XHTML/XML, with documentation on content management systems, php, etc.
You'd soon find that in the beginning your development would be gradual and at best, slow. If you put in sufficient effort, you would find that you get to the point where you can quickly design sites confidently, which best illuminate your content.
You should be familiar with this and this
Try this Web Design from Scratch
I understand by website you mean some kind of web-app. And by design you mean, not just the page design but the design of the web-app. First, you have to understand the anatomy of a web-app. The major components are:
Database is used to store user and application data for long term. A database provides query functionality (SQL), backup on one installation and restore on another, triggers when a data entry changes, and constraints that must be satisfied by the data tables.
Web Server, also called Http Server hosts the web application.
Web Browser such as Internet Explorer or Firefox.
When a user types a URL into the web browser, the web server forwards the URL to the corresponding web application. The web application performs the needed tasks (which may involve reading or writing into the database) and returns a new html page to the user via www.
Some components of the web application are:
Database access objects are representations of objects that encapsulate interaction with database tables.
Business Logic is the main logic of the application. Here we implement the search functionality using Lucene library, for example.
Action Handler handles a http request received from the user, for example when she types a URL or when she clicks on the "submit" button. These are Http GET and POST requests. The Action Handler uses the business logic to drive the actions.
Data view on the web brower is constructed using some template library (which usually produces javascript user interface code for the web browser). For interactivity one may use Ajax techniques.
Almost all web-apps separate the model, view and controller of a web application. The view deals with the display, the model deals with data and the controller deals with control/functioning. See http://www.uidesign.net/Articles/Papers/UsingMVCPatterninWebInter.html.
Several frameworks implement MVC. The most easy ones to get started are Ruby on Rails and Django (over which an open source social network called Pinax too is written). There are much more comprehensive frameworks and libraries in java too (for a single web appl you may need to join several of these libraries), such as spring, webwork, tapestry, lucene (for search), sitemesh (for page decoration). Many java web apps run on tomcat web server and with mysql database.
I started with http://w3schools.com. Make sure you're using Firefox and the Firebug addon. Get your hands dirty then get familiar with the web design community.
I have CSS Mastery by Andy Budd on my desk and it's a good, readable, short, yet deep guide to CSS.
Don't Make me think has also become my mantra of web design.
Overall, you're going to produce a lot of crap--as I have--before you get good. If you have someone to look over what you're doing that'll be the best help. Personal drive will matter the most in the long run though, so stick with it and keep learning.
Liz Castro has a good book too.