We have an existing cross-platform Mobile Application, that also has an accompanying web application, that uses AWS as a back end (RDS for Database, Four server instances, and a Load Balancer to distribute traffic). APK and IPA files are packaged and sent to the stores, while components are retrieved from our server per request, which enables us to reduce the number of store builds, and make the process easier for getting changes out to clients.
We are at the stage of Development that we need to move to another platform to better facilitate our fast growing client base.
Due to the conditions upon our clients, these things must be considered.
must be cross platform (Android / iOS).
must be offline based (users need to be able to access without an internet connection)
must be able to sync with an existing database when there is a connection
requires Authentication
Cloud based (? may not be the right term, but meaning the ability for us to store components on a server and have a device check for updates and download a local copy - enabling us to work and distribute fixes faster)
Ideally compatible with AWS
We are currently looking at Xamarin to facilitate us for this move, however there is a lot of documentation and plugins out there to do all sorts of different things.
As developers, we all have some .net / c# experience, however none particularly with Xamarin.
We have a particular timeline that we need to adhere to (and need to ramp up in the next couple of weeks), and right now are essentially stuck in Limbo in a research phase, as we can't afford to get some things right. We are unable to move forward until we know Xamarin (or some other framework) is able to do everything that we need it to do.
It's hard to escape from the 'code it all ourselves' mentality - especially as we don't know where to start looking in terms of third party packages for Xamarin, and their documentation itself.
A lot of documentation mentions various systems of Azure - we would not be against moving to Azure over AWS if it _had to be done*, but because of the existing infrastructure with AWS - staying with AWS is obviously the preferred option (users need to access the current system whilst we build the new system)
This stack overflow post is to ask for recommendations, comments, or other observations on anything and everything involved with the process in regards to choosing frameworks, design patterns, methodologies, third party packages, etc.
Obviously we would like to use best practises for everything moving forward for optimum scalability and cleaner, more robust code. It's just hard to know where to start!
Any input will be highly appreciated.
Cheers!
edit: I am aware that this is 'asking for recommendations' which is 'specifically off-topic'. I have read the posting guidelines about open ended discussion, and am quite confident that this case is different. There is an underlying problem here, in that we are seeking advice on combinations of frameworks and plugins that are fully compatible with all of the items in the list (above)
Let's try to breakdown each of your requirement and constraint mentioned in the question.
1. You need a offline first architecture (With Sync mechanism)
Xamarin + Azure would make a good comdo for you, as it would support offline storage out of box (With a simple PullAsync call).
Albeit there are AWS SDK available for Xamarin. Here it goes http://docs.aws.amazon.com/mobile/sdkforxamarin/developerguide/setup.html
So the call is yours. There are few other ways to achieve caching offline storage in Xamarin, you can build upon those strategy in your logic. Alternatively there is a very interesting C# library Akavache for caching and offline storage.
2. OAuth 2.0 Authentication
Xamarin has a very good library named Xamarin.Auth. Though I would not say it is very easily extendible at this but there has been some serious work going on from Xamarin on this library.
But I would say it is very easy to use. The apps I have developed so far that includes - Google OAuth, Facebook integration, Microsoft account integration. It worked fine for all of them.
3. Cloud based distribution
There are nice tools available with Microsoft. Which makes the distribution easy. Have a look at https://mobile.azure.com . Also hockeyApp is good for distribution I found.
Where to start:
A very good starting point for you would be https://channel9.msdn.com . Just go there search with keyword "Xamarin" and view some videos. May be all these cross platform dynamics will be much easier for you.
Overall I found Xamarin a cool product to work with. Because anything that can be done in native Objective C/Swift or Java can very well be done in Xamarin using C#.
Related
I am trying to evaluate whether Xamarin would be a good option for my project. The project is a large, complex app for Android and iOS with a lot of client-server communication. The user interface is a major focus and has to be really fast and smooth. Also, we plan to make large use of UX graphic effects (comparable to the Spotify app).
For now we are planning to go for two separate native apps using Java/Objective-C. However, the possibility of cross-platform code sharing would be very convenient for us of course.
Most opinions I've heard so far say that Xamarin - although far better than HTML5 apps - cannot match the UX of a native app. Also, I tested the following applications made with Xamarin (on Android):
Rdio
MarketWatch
Busch Gardens Discovery Guide
Sqor
Storyo
From my impression, none of them could quite match the speed and smoothness of a good native app.
If our focus is on a top notch user experience, would Xamarin really be a viable option? Can it really match a native UX? I am particularly looking for opinions from developers who have experience with large and complex cross-platform Xamarin applications. A few critical voices would be very helpful.
Thank you a lot!
I'm on the Rdio mobile development team, so I can make some personal reflections from that standpoint.
Xamarin allows you to write native applications in C#. Any slowness, jankiness, ugliness or bad-appiness usually has nothing to do with the Xamarin layer itself.
You save some time being able to share core business logic between your different clients, but you're still writing the UI from scratch, specific to the platform. You're just writing it in C#.
But while you save that time, you're spending it in other ways. All of those SDKs you want to use probably aren't compatible with Xamarin out of the box. You won't be pod install'ing that iOS framework, and you might be reinventing the wheel for handfuls of things. Xamarin takes advantage of the NuGet repo so you have a library of components that handle many of the things most people need (Analytics, Testing, Facebook SDK, JSON parsing, Database, etc etc) but it doesn't cover everything. And it certainly doesn't cover stuff that's out the day of an Apple or Google product announcement.
Any 3rd party code that you do want to import into your project will be done through writing custom bindings. While not usually difficult, it is time consuming. Xamarin has a team of people that specialize in assisting you in this. This fact speaks to the process being messy at times.
So while the slowness, jankiness, ugliness or bad-appiness probably isn't the fault of Xamarin, it might be the fault of you spending time in places you normally wouldn't, or not being able to take advantage of features you normally would. If that 3rd party partner SDK is giving you problems, your troubleshooting may take twice as long because there's a layer that you don't control.
UI is a wash. You're writing it from scratch anyway.
Business logic is shared. Depending on the app that might be a win if you architect your application to take advantage of it.
Compatibility / bleeding edge ability will be lacking. That might not matter to you at all, or you might be the person wanting to take advantage of that hot new API in the next OS release the day it's announced.
My personal thought, without knowing specifics, is if you want to build an application that you plan on being around years from now, and that will take advantage of the latest and greatest, I'd tell you to write natively for each platform. Unless you can really see huge gains in sharing that business logic the upfront gains are minimal. Or if you really like C#.
Xamarin uses native controls. So you design a fully native UI per platform. The users can't see that your App is made with Xamarin or Java/Objective-C.
There are sometimes performance issues in conjunction with the platform independent UI wrapper Xamarin.Forms. But you're not forced to use it. When you have still performance issues in your Xamarin.Android or Xamarin.iOS app then you produce them in your code.
There are benchmark results for Android apps comparing Xamarin.Android and Java apps: Does anyone have benchmarks (code & results) comparing performance of Android apps written in Xamarin C# and Java?
As you can see Xamarin's internal performance became better and better over the time.
Conclusion: Yes, you can write smooth native Apps using Xamarin.
I have a certain online application that generates reports(and prints them) based on some repository of information. Now I would like to make an offline application which is provides the same experience and in which the repository is pre-loaded into the users' computer. What is the best way to convert this online app to offline app. The first thing that came to my mind was setup a local server and database. This ensures the experience is consistent. But I'm open to other options, such as storing the data in a file system and then loading it via flash/flex based apps or C# or Java. The objective of this offline app is to provide the functionality(report generation) to users where internet is not feasible.
I am not sure about the windows aspect of your question, but if I was doing an offline web based page(s) I would be looking at a LocalStorage database (though it does have some downsides), but there are other alternatives such as WebSQL and IndexedDB.
If you have reports, do they still have value when they are out of date? Do you need to store the configuration of those reports or is it all just read only?
Shameless self promotion, I have a project that is designed to handle database synchronization, though it's not done, it's close. You can see it (with an ugly but very functional) demo at https://github.com/forbesmyester/SyncIt
What's your experience in using web technologies (HTML, XML, CSS, JavaScript) to implement part of the functionality of a GUI application? Pros and cons, please.
No servers, relational databases, AJAX, or cookies for session management, nor an existing webapp either, but rather a GUI app that uses web widgets (like Qt WebKit) to render and handle substantial parts of the UI, while taking advantage of a GUI framework to achieve an even richer interaction and better desktop integration.
I've already validated that the approach is possible using PyQt. Content can be rendered from the file system or from strings, and URL requests (images or clicks) can be captured and served by the form's event handlers. CSS and JavaScript are supported, perhaps with some limitations.
# ...
self.webView.page().setLinkDelegationPolicy(
QtWebKit.QWebPage.DelegateExternalLinks
)
#...
class TotiMainWindow(QtGui.QMainWindow):
def linkClicked(self, url):
pass # events arrive here
Note: This question is different from this one and this one made before, among other things because there is no requirement to use web technologies on the GUI, but there is the requirement that the application should work without a network connection available, and should integrate well with the default desktop over different platforms, without previous infrastructure requirements (no .NET, Java, browsers, or database servers).
Note: I posted a different version of this question on PMS but found very little experience with this approach there.
Closing Note
I just found most of the information I was looking for in a series of blog posts by André Pareis.
I think the largest advantage to using web markup like HTML/CSS and other web technologies is that desktop apps may very well have their days numbered.
As we speak, Google engineers are working on the Chromium OS, which essentially consists of a single GUI application... the browser...
Now, while nothing may never actually come of it, there is clearly a rising trend in the number of applications accessible through a web browser, accessible anywhere. It seems to me that this is the future of application development.
By using these technologies, this becomes one less headache you have to deal with when or if you determine that your app should be available as a web application.
Update: A few years ago, we developed an Agent Desktop for our call center that is essentially a local application that opens sockets to integrate with the phone system. The user interface the agents use is built with HTML, CSS, and JavaScript, and the experience is stunning. When we released our latest update in 2010 with a professional CSS redesign, our agents were all very impressed with not only how easy it was to interact but also how easy it was to use.
In the future we will port this 100% to the browser, but for now it needs to be a local application because of the COM integration with the phone system.
We did exactly this for a project back when Windows XP was new.
This gave my team several benefits:
A good-looking UI with relatively little effort
Easily change the style of the UI in a consistent manner using CSS
Relatively simple integration with C++ (invoking functions from the ui and vice versa)
The drawbacks we saw were:
Some not-so-good firewalls considered accessing internal resources (ie other html pages in the ui) to be a web request
Adding and accessing the needed resources could in some cases be a bit cumbersome
It was possible set properties in Internet Explorer that would prevent JS from running in the application
Note that some of Windows XP:s programs are using this approach.
This probably works best with small, more Wizard-like parts of the ui (which our ui consisted almost entirely of).
I have since then not really been involved in ui projects, so I cannot really tell you whether this approach is still valid... I know that MFC-based applications will let you use HTML-based dialogs though.
In a similar situation in 2005 I created a stand-alone webapp using XForms, CSS, JavaScript, XML and XML Schema for offline data retrieval and verification. With a good XForms -> HTML + JS transformer (Chiba) it did the job with no bug fixes after the initial release. It was used for 6-12 months (IIRC) by about a dozen engineers for a project gathering test data in the tunnel of the Large Hadron Collider. The biggest surprise of that project was just how much you get for free when going for a web platform, even for offline use. Highly recommended.
The major problem is that it reduces your development speed, or the quality of your user interface. A lot. Unless you're using Seaside, it is much faster to develop a desktop app.
There is quite some number of applications built on top of Mozilla platform. It isn't 100% web technology, as instead of HTML you use XML based XUL, but the rest is indeed web stack (JavaScript, CSS). The most successful of these it the OpenKomodo and it's commercial big brother Komodo IDE.
On the other hand, as far as Qt goes, the newest version 4.7 you can build GUI using QML language. Don't let the name mislead you, it's not markup, it acctually JavaScript with app-specific extensions.
I'm a junior VB.net developer with little application design knowledge. I've been reading a lot of material online regarding different design patterns, frameworks, and methodologies. It's become a bit confusing for me.
Right now I'm trying to decide on what language would be best suited to convert an existing VB6 application (with SQL server backend.) I need to update the UI and add more user functionality and reporting capabilities. Initially I was thinking of using WPF and attempting the MVVM model for this big project. Reports would be generated from SSRS.
A peer suggested using ASP.net and I don't have enough experience to determine what would be better. The senior programmers here are stuck on using VB6 and don't have any input on what to use. They are encouraging me to use the latest technologies.
This application would be for ~20 users in a central location. Ideally I would stick to a Microsoft .net language. Current interface is similar to a datagrid table where the user would click in to see the detail of each record. They would need to have multiple records open at any given time.
I look forward to all the advice I can get.
EDIT 2010/04/22 2:47 PM EST
What is your audience? Internal clients within an intranet
How complex are the interactions you expect to implement? not very... displaying data from SQL server to UI. Allow user updates to said data. Typically just one user modifying a record.
Do you require near real-time data updates? no
How often do you expect to update the application after the first release? twice/year
Do you expect a well-defined set of client platforms? Yes, windows xp environment, potentially upgrading to Win7. Currently in IE.6 moving to IE7 or 8 within a couple of months.
Do users need access from anywhere? No, just from their PC.
What would be wrong about building a simple ASP.Net application in VB.Net using Gridviews for allowing the data access and manipulation? Seems like a simple ADO.Net trial application if you aren't familiar with it in the beginning you will be by the end. CRUD applications are pretty common so it shouldn't be too hard to build it and then refine it as more requirements become apparent.
Sounds like you need to use a web-based solution--this eliminates alot of your potential distribution woes with multiple users. You could use silverlight, but if you are locked into SSRS, this might not be the way to go.
The term is getting 'hotter' with Microsoft Azure and Windows 7.
What are the benefits + how does the status quo of desktop computing now change? Does the machine no longer need an OS installation (or a highly stripped down version of a typical OS)... what is needed to interact with the 'Cloud' ?
Update: Received my first RTFM on SO today.
To elaborate.. I'm interested in knowing how different is the 'new way' w.r.t. the services provided by a typical desktop OS today (read Win XP/Vista, linux flavors galore, etc.)... NOT the benefits of cloud computing.
Two buzzwords.
Basically its Microsoft's form of competition against Google's recent web-apps boom. So if you want to know what it's all about just open up google docs and gmail, and there you go :)
Now on a personal note, I'm glad Microsoft and Apple(Mobile Me) are trying to fight back against Google. We need the competition, so us the users can choose and get better apps.
Also I'm really not a fan of any corporation, so I'm not all that excited about Google killing off everyone else any more than Microsoft doing the same to others.
When Microsoft says Azure is a Cloud OS, what they mean is that it provides the same kind of services to developers targeting the "Cloud" abstractions that are akin to what a Desktop OS provides developers targeting desktop.
Amitabh Srivistava gave a great interview on Channel 9 explaining it. Basically, if you want to write a notepad application for a desktop user, you don't have to be concerned with writing code that interprets key strokes from the keyboard, or that sets up communications with a printer. This is due to the desktop os. Similarly, Azure lets a developer focus on their cloud app better by abstracting things like load balancing, authentication and authorization, failover, and a lot of concerns that one would normally have to address when developing for the Cloud.
Old school network diagrams always showed the internet as a cloud. Microsofts approach is still a client-server model, although a real 'cloud' os in theory would be a SOA architecture of loosely fit components interconnecting and working together without really being aware of eachother. Example: creating services for email, document authoring, file storage, etc- which could all be interconnected by different services that don't erally need to be aware of the final product.
So different way of thinking of it: the 'system' exists in the network- not one single location.
Gains: Transparency, redundancy (not only of each service, but for replacing parts if vendors drop out) and availability (as long as you are also connected to the network).
Losses: Vendor lock-ins, vendor's dropping out, interoperability nightmare, as far as I know- there are no real standards for this model.
Microsoft did not coin 'cloud' computing term. Please refer to the wikipedia entry for a more specific definition and etymology.
whats with the RTFM questions on SO lately? unless I'm missing some deeper meaning, your questions are obvious.
http://en.wikipedia.org/wiki/Cloud_computing
Cloud computing is Internet-based
("cloud") development and use of
computer technology ("computing"). The
cloud is a metaphor for the Internet
(based on how it is depicted in
computer network diagrams) and is an
abstraction for the complex
infrastructure it conceals.[1] It is a
style of computing in which IT-related
capabilities are provided “as a
service”,[2] allowing users to access
technology-enabled services from the
Internet ("in the cloud")[3] without
knowledge of, expertise with, or
control over the technology
infrastructure that supports them.[4]
According to a 2008 paper published by
IEEE Internet Computing "Cloud
Computing is a paradigm in which
information is permanently stored in
servers on the Internet and cached
temporarily on clients that include
desktops, entertainment centers, table
computers, notebooks, wall computers,
handhelds, sensors, monitors, etc."[5]
http://en.wikipedia.org/wiki/Azure_Services_Platform
Microsoft's Azure Services Platform is
a cloud platform (cloud computing
platform as a service) offering that
"provides a wide range of internet
services that can be consumed from
both on-premises environments or the
internet"[1]. It is signficant in that
it is Microsoft's first step into
cloud computing following the recent
launch of the Microsoft Online
Services offering.
...
The idea and push from Microsoft to
compete directly in the software as a
service model that Google's Google
Docs have offered is increasingly seen
by them and others as an important
next step in application development.
In this idea, a software doesn't have
to be installed and managed on the
user's computer. It also allows files
and folders to be accessed from the
web.
So far, it looks like the idea of having software & your data hosted at msft's data centre.
SOA seems to be related to what cloud is offering.
No need to have local software (office will run from internet, your docs will be saved there. so that, you can access it anywhere). I think, the target could be big companies - thereby giving them services (software + hardware (data storage + processing power)) on subscription basis.
An expert can shed light on how this can be useful?
Will people be willing to put everything in the cloud?
Cloud is Time Sharing. Us old timers remember those days. You either wrote your own apps and ran it on their (the Time Share/Cloud providers) systems or you use the software they supplied. Usually word processors and accounting apps.
Google Apps is cloud. And since you get HD space you can already serve up your own app running on their systems.
Time Share was all the rage in the 70's and 80. Cause maintaining a system of your own wasn't cheap. Back then the smallest system any company ran was a mid-range (like Honeywell, AS400, Dec, etc, etc). Fell out of favor as the PC became popular. I remember when Lotus 1-2-3 came out and everyone predicted it would destroy what was left of Time Sharing. And it (along with dBase and other aps) did.
It's funny how we re-invite everything.
PS: Forgot one thing about Time Sharing. Since the Net wasn't around, you had to schedule your time. SO your staff would go to the providers Data Center and work. It was like renting space and the systems. Time Share and Cloud operate differently, but the function is the same.
Well like many new terms, there can be more than one answer. Frequently it can be defined as a compute platform, where the developer doesn't have to worry about resource management, scalability or hardware failures, because the cloud infrastructure handles it. Here is a link to some information the company I work for has:
http://www.appistry.com/resource-library/index.html
There are some good white papers linked here that might be helpful to you.
-Brett
A cloud operating system primarily manages the operation of one or more virtual machines within a virtualized environment.
Microsoft Windows Azure and Google Chrome OS are among current examples of cloud operating systems.
Azure App Service is one of the common and most used services. While it is possible to immediately deploy apps, jobs etc., to the app service, a common factor that baffles decision makers is the wide spectrum of the tiers (options of plans) available in the marketspace. To know more details,visit:https://www.impigertech.com/blog/azure-app-service/