Approach to developing an application across many Nokia devices - c++

First off, greetings everyone and thank you for your interest in my question.
I'm currently working at a mobile startup. Our product is a communication app for Android, iOS and BlackBerry devices and we're looking to expand onto some Nokia platforms.
I don't know a lot about Symbian details as I've never actually programmed in the platform before but this is all of the information I was able to gather.
The platforms to support are Symbian S60, Symbian^3 / Symbian "Anna", Maemo + Meego.
In order to accomplish this, there's several tools at our disposal but we're not sure which ones to use.
Nokia Qt appears to be unsupported on Symbian S40 devices (we seem to be stuck with J2ME) and Symbian S60 devices pre-3rd Edition Feature Pack 1
On Symbian's C++ we can't rely on C++'s STL. This means that we can either create two versions of the same software or create our own STL that's compatible with Symbian (I'd like to avoid that).
Approach
Among the team the consensus seems to be to split this into two logical chunks:
Core business logic + libraries in C++
Device specific UI branches using Qt or native UI tools
With all this information in mind, I ask:
What is the general approach for this problem? Is there any considerable flaws with the one mentioned, namely incompatibility or inconsistencies with Qt on older platforms?
What pitfalls should we avoid to ensure compatibility and performance of the app across all Nokia devices listed?
Is there a way to get around Symbian's C++ limitation of the STL? Can we bundle the Qt sources somehow?
Suggestions and other approaches are welcome. Thank you for all your feedback.

You should consider that Symbian is a dying platform, so I would not invest huge development effort into a Symbian application. And even more so I would not use Symbian C++. Qt is a promising platform but Nokia/Microsoft announced that there will be no Qt port for Windows phone (which might be interesting for you).
Maybe you should support Nokia devices only by Java ME because Symbian has big market share but the most devices are not smartphones where you can run a Qt app.
Your approach sounds very idealized, but I am not sure if you can use the C++ libraries you mentioned for the business logic from Java ME. Is that possible?

There are STL implementations that are possible to use on Symbian.
I was once part of a team hat used a C++ core (with STL) on Symbian devices ranging from S60v1 to S60v5 as well as UIQ, S80 and S90. The same core was also used on windows mobile.
We used STLPort for the STL implementation, but I have been unable to find that specific version again. I do believe there are other Symbian STL implementations out there.
On the other hand S60 device have a very competent J2ME runtime, so if you have to develop a J2ME app for S40 devices you might as well use it on S60 as well.

I am not more experiences as you but according to me Qt is good for Application development.Write code once to target multiple platforms
Qt allows you to write advanced applications and UIs once, and deploy them across desktop and embedded operating systems without rewriting the source code saving time and development cost.
Thanks

Related

It is possible to just use QT and WebAssembly (instead of HTML + CSS + JavaScript) to develop a front-end web?

I am a C++ programmer, but for some reason, I have to develop a website by myself(My own commercial project). I don't want to take a lot of time to study JavaScript and something else. It is possible to just use QT and WebAssembly (instead of HTML + CSS + JavaScript) to develop a front-end web?
Yes, it's absolutely possible and I'm currently doing it for a project but you should do it carefully based on the project requirements, running environment and your own backgrounds.
Here are some problems you may encounter:
The output .wasm file may get too large. Generally, it won't be suitable for public domain applications.
In low-end devices, maybe you find it laggy if you don't do enough code level optimizations.
Threads are not officially supported yet (as of Dec. 2019) by major browsers but tech-preview is available. This is not a real big problem as it would be a standard feature soon.
Native virtual keyboard won't work on mobile devices but the work is in progress.
These were my own major problems with Qt for WebAssembly.
Despite this, I find it much more flexible than HTML+CSS. QML is really a nice language for UI development. Creating animated UIs is quite easy and straight-forward.
You can also use many JavaScript libraries in your QML code like Lodash and Moment or any other js library that does not refer or manipulate window DOM.
Yes, it is possible. But you should do not do it if only reason is reject for learning new technologies.
For now (I'am writing this answer when Qt 5.14 is present) Qt for webassembly is deployed as official platform. Unfortunately it is young platform support with a lot of problems and possible future changes. Qt team do really good job so next version will be better. 5.14 is much better than 5.13 in webassembly context but still need fixes.
You should know Qt for webassembly will support only a few Qt modules, excluding widget. Yes, you can only use QML for GUI.
Qt for webassembly was created for the purpose of port one code base in other platform (it it generally Qt develop way, please see Qt for MCU). With other technologies in this stack like QRemoteObject is very interesting technologies. It was not created for websites in normal network. Main Qt for webassembly target are internal network systems and remote control of devices. Pay attention about this.
Unfortunately, not all browser will support webassembly right. Please see Qt for weassembly support notes.
Additional, in Qt you can't find build-in rest-API handle or other standard web technologies to integrate with your existing backed.

Windows phone 7 native code support

2 questions:
Can someone tell me if unmanaged c++ code will
be supported in future versions of Phone 7 OS for all developers?
What are MS reasons for not
supporting unmanaged c++ code?
This answer is purely speculative, but I feel that most others who have answered this question miss the point by a long shot. Let's for a moment assume that this is not a vindictive decision by Microsoft, but instead actually a very well thought out engineering decision that has absolutely nothing to do with content restrictions or otherwise. Those issues are just a bonus for MS
Microsoft is entering into the mobile market, this time for real it seems. Pretty soon there will be tens of millions of Nokia phone being shipped using Windows Phone and whatever they get on top of that will just be gravy. Windows Phone though still hasn't really found its home.
In the next year or two, phones, tablets and laptops will finally start converging into a single device. People will carry their phone in their pockets, but that phone will also be the CPU unit of their PC. That means that by simply sitting near a wireless HDMI monitor and connecting a keyboard and mouse via wireless USB (or bluetooth if we're all unlucky), the user will have their entire PC with them at all times. Tablets will become just a battery powered touch screen which interfaces to the PC in your pocket.
So, all software written for Windows Phone should be able to run unmodified on a PC, a tablet and/or a phone. This is because there's a huge chance that the PC you're running will be either x86 or ARM based running Windows 8. When the PC is in your pocket, the user interface you'll see will be the Windows Phone GUI. When you're hooked up to a monitor, you'll see the ribbon interface. But the underlying OS will most likely be Windows 8, not the Windows CE that is currently used.
Based on all this, the only way Microsoft can insure that developers who invest in producing apps for the Windows Mobile market will not be screwed and that users of Windows Mobile devices won't be shorted when the newer platform comes around is to ensure there is a standard system for running apps on all these processors.
Even now, writing for Honeycomb is a nightmare since if you develop native code, you have to support both ARM and x86 and there's no real support mechanism for it. The only solution is to develop, package and ship two versions. Writing apps for iDevices are a little easier since there's no overlap. x86 on desktop, ARM on device. If you have to use native code on device, ARM is all you need. Even then, there is fat binary support on both device and desktop, so this won't be a problem except when optimizing.
In the end, the decision by Microsoft to stick strictly to .NET is probably a good one. Once they have a gazillion Nokia phones on the market and things have settled a bit, native code could be a real possibility.
These answers are for the application development perspective. OEMs can write native code today, as that's how they create drivers, but that's not open or available to most developers and therefore of no use to most.
For #1 Microsoft has made no announcements, so only Microsoft knows the answer and they're not saying.
For #2 it's all about code security and overall platfrom stability It's very tough to sandbox native code and they don't want your app being able to affect other apps or the platform itself. The general idea is that you should be using Silverlight or XNA for application development, so that's what they expose.
Windows phones will go nowhere with native support. Games and other more intensive apps are driving sales. Android was forced to blow the lid off of its NDK to support the games industry. As far as supporting multiple processors, etc., those of us doing this kind of work have been doing it for a long time, so its no problem. Already handling Intel and ARM without a problems with our systems.
EDIT, finally: for WP7 unmanaged code won't ever be supported, but in Windows Phone 8 - yes it will! They've just announced it. Native apps, C/C++, iOS/Android portability and code sharing, DirectX. You'll need Visual Studio 2012 and Windows 8 for WP8 development, though. Looks like VS2010 is not getting the requisite WinRT SDK.
The nongame UI, however, will still be XAML-based. Win32 API will not be supported. They're pushing a model with managed UI layer and a native middleware beneath it.
SDK will be available later this summer.
For the sake of posterity, here's the pre-06/20/2012 answer:
Microsoft probably can.
To ensure platform closeness, as a means for attaining stability and UI consistency. To enforce app isolation. Also, to make jailbreaking/rooting harder.
EDIT: if you want a native SDK on WP7, like I do, please go sign this petition and/or that petition. Thank you!
EDIT: see this.
EDIT: also this. Still not official, but this rumor moves the timeframe for native app support even closer - to the upcoming Tango release.
I believe MS will support native development like C/C++. Really. Seriously.
Because, for end users, one of the killer app is game. And Most of game codes are based on C/C++. JS or C# based codes are exist, but meaningless from industrial perspective. Consider big players in game field like Unreal or EA. They made huge investment on C/C++ codebase. They won't give it up. In other words, MS has no power to force them to spend money for .NET. Even Xbox360 development offers C/C++ development. Because of that.
And leading platforms like iOS/Android all supports native development. WP can't bear up the situation without any game from big players. MS really wants 3rd path games, and offering native code is the only way to get them.
Of course, this can be applied to other apps which are not game, but games are biggest one. When C#/XNA just came out, there's no library. People had to make everything themselves. Now there're a little more, but still meaningless for professional games.
If MS won't offer native environment, just don't go there. MS wants to make developers to use managed .NET code, but .NET has too many limitations can be solved with only unmanaged code.
The only question is just when will MS support native development.

Can I make a rather native C++ app with Android?

I'm interested in the following features:
Writing an app for Android Market that is written completely in C++ (a port of existing product actually).
Use fast screen-buffer pixel pushing (or rather using OpenGL ES for this).
Grab user input and direct it to C++ code.
Is it legal to write such an app for Market? Is Market policy somehow strict to such things?
As of NDK r5 with Android 2.3 (Gingerbread) this is possible, although I assume only devices to support natives apps must have Gingerbread on them.
From the native-activity sample:
The Android SDK provides a helper class, NativeActivity, that allows you to write a completely
native activity. With a native activity, it is possible to write a completely native application.
NativeActivity handles the communication between the Android framework and your
native code, so you do not have to subclass it or call its methods. All you need to do is declare
your application to be native in your AndroidManifest.xml file and begin creating your native
application.
It is really not my cup of tea but there is something called Android NDK (Native Development Kit) to use if you want to write your program in C. Not sure how the C++ compiler support is though.
As far as I know your app can be almost 100% native code but keep in mind that by walking that way you will probably have a hard time supporting the different CPUs out there in Android hardware. If you need to bootstrap the native code so that it is started from java it is probably not a very big problem for you.
I found a few different tutorials when googling for "Android NDK". This one is a very minimalistic Hello World. Obviously you want something much more than a library that returns a string to java but it is a good first start and you will probably have to do all of the things described. Do a search using NDK and Android as keywords and you get a good selection. I see no reason to list them here as such lists tends to be outdated and broken within a year or so.
I guess the official Android Developer site from Google will stay put and be updated on new releases of the platform, it has a link to the current NDK.
With Gingerbread (Android 2.3) it looks like you can build your entire app in C++.
cf:
http://phandroid.com/2011/01/11/android-developers-blog-awesome-ndk-leads-to-awesome-apps/
"
With the latest version of the NDK, r5, many big improvements have been made to coincide with the release of Gingerbread. The most major is the ability to code a native application for Android 2.3 entirely in C++. This means even programmers and developers with no Java knowledge won’t have to implement a single line of that code..."
Can't vouch for the veracity of this blogger, however, from what I have read, it appears you can do this
There is no 100% native solution but what I think you are looking for is the Android NDK (Native Development Kit)
From their site "Please note that the NDK does not enable you to develop native-only applications. Android's primary runtime remains the Dalvik virtual machine."
I believe it lets you make calls to your own native code from an Android application
I have personally never used it for my games, but I am sure it would help on a lot of things (like being able to manage my own memory and not have "lag" do to the garbage collector)
conversations in this thread can help you.
http://groups.google.com/group/android-ndk/browse_thread/thread/50362904ae0574cf
essence is,
It is possible to make Native only apps and Android Market doesn't restrict you either.
But with limited support for native development, there is high chance of using some of the non standard functionality which might break in future releases.
http://developer.android.com/guide/basics/what-is-android.html
"The Android SDK provides the tools and APIs necessary to begin developing applications on the Android platform using the Java programming language."
http://arstechnica.com/open-source/news/2009/06/android-goes-beyond-java-gains-native-cc-dev-kit.ars
In general, you don't. There is some limited C++ support through JNI, but it is mostly intended to supplement Java code, not replace it. There's no framework/API support (AFAIK) for C++, so doing this isn't really an option.

Real life use for Qt (outside of Nokia)

Is Qt an interesting platform for business apps development, outside of Nokia phones ?
Why ? Strong points ?
Thanks
I like Qt because:
Very well-designed framework, e.g. signal-slot, model-view, graphics view/scene/item/proxy, painter/paint device/paint engine..., too many to be listed here!
Excellent documentation!
Cross platform language/API, as well as tools like UI designer, creator, and so on.
Rich features, e.g. graphics framework, network library, database engine, and so on.
Active community, and active development.
There should be more. If you have ever used it, you'll find it's easy to build your framework upon Qt.
I didn't have any complain to Qt. If I have to say at least one disadvantage here, "convention". You must adopt the convention of Qt, e.g. You have to use moc to make the meta object of your objects, and it's easier for developers to use Qt's vector, list, auto_ptr than STL, tr1. But I never found any issue caused by that. On the contrary, it works very well.
In my opinion, Qt is the state-of-the-art C++ framework in this modern world!
P.S. There are a lot of commercial applications built on Qt. You can find it under Qt's official website. But I'd like add one more here: Perforce, one of the top commercial source code management tools, built its client tool on Qt for Windows/Linux/Mac.
yes it is .. just look at kde apps :)
or see more applications made by qt
and it has alot of bindings in many languages
Documentation
cross-Platform IDE
further reading
may be this is not so related to the question ... but my first deal with qt was just great starting from their well organized Documentation to their great widgets
the GraphicsView is just ammazing ! :)
It's about the only current/modern C++ gui library on Windows.
MFC is so old you have to write comments in Latin
WTL would be nice if they had finished it before abandoning it.
Winforms/WPF + managed C++/CLR - all the fun of several incompatible new technologies at once.
Bad points:
To fit on lots of platforms they have invented their own solutions to things that are now in the STL/Boost
The signal/slot mechanism - tricky to debug and silently fails (with no error) with simple typos.
Although everything is possible it's sometimes a lot of effort to do simple things (they do love MVC) compared to Winforms.
Qt is simple
Qt is powerful
Qt is NATIVELY-CROSS-PLATFORM
Qt is REALLY-CROSS-PLATFORM
Qt is comprehensive (but the Media side of it still needs to grow)
Qt doesn't require Garbage Collection, but it embeds a GREAT model of memory management that makes you forget about memory deallocation
Qt is solid
Qt is modern
Qt proposes some new paradigm of programming that are really good (Signals-Slots)
Qt runs a lot of VERY successful software: (Skype, Google Earth...)
Are those points strong enough?
Maybe you have heard about Google Earth which happens to be programmed in Qt too.
That aside, I like Qt for my in-house development because it
is very well supported and documented,
allows me to write simple and decent-looking apps that are
works cross-platform for Windows and Linux with little effort, and
contains nice to have components for database access, regexps, guis, xml, ...
I also use the Qwt widgets for easy real-time plotting on top of Qt.
I really dont understand whats the point in underestimating tools/frameworks which makes things easy for programmers. Qt is too good for GUI development, I would say its much better than any current existing crossplatform app development suite.
So many advantages, I have been using it for more than three years now for a product to be deployed in Linux/Win environments. The app is thread intensive and initially we had a tough time using pthreads and its conterpart for windows. Then we switched to Qt(and QThreads eventually) and things were a breeze...
Backed by active development, a highly helpful and supportive community along with excellent documentation, training, certification programs, videos, forums... its easy, fast and effective to develop in Qt. You should see the video which they create a web browser in just five mins!
Its really 'cross platform', and it doesnt have a software wrapper(like Java does) to enable this which makes it faster. Cmon, we all know java apps have buttons which takes a second to respond to even a simple 'click'.
I hope Qt will someday do a take on Java. :D
after all, 350000 developers cant be wrong when they chose Qt.
Pixar uses Qt (or at least, used, as of 2005) internally for certain parts of their tool suite (called "Marionette" in the marketing) collectively called Menv, ("men-vee" for Modelling ENVironment)---at least for their lighting sub-tool Lumos.

I'm building a touch-screen application for a mobile device. What C++ toolkit should I use?

Building a touch-screen app for a mobile device, around the size of a book. What C++ toolkit should I use? I was thinking about Qt, or gtkmm with hildon.
Thanks!
Use the frameworks that are supported/recommended by the OS on the mobile device.
After that, if you get more than one answer to the above question, check to see which one features the features you want for your application.
After that, pick the one done in the programming language you are most used to.
Good luck.
M.
+1 Qt. Qt's framework is great. and it goes LGPL now.
It might be worth looking into easyGUI. It it can be used with just about any OS and supports just about any device. The only downside is that it costs money.
What I really think you're saying is that you're porting Linux to a completely new device, e.g. one of these electric book things.
I'd suggest you port Android (which is Linux down deep so that part of porting is much the same) and use Java for your UI.