QtCreator is a very flexible IDE and can really be adapted for a lot of things. I usually use it to develop mobile applications for Nokia N9 and BlackBerry 10, but it can be used for more generic tasks. In my case I wanted to be able to develop a Qt application using my desktop PC, deploy it and run on a remote (actually it's on the same desk) Linux machine running Xubuntu.

Doing this is quite easy and you don't need any specific plugin on QtCreator, but be sure to have at least version 2.6.x. Other than QtCreator you also need two Linux based PC (I used Ubuntu 12.10 for my development machine and Xubuntu 12.10 for the remote netbook) and an SSH account on the remote PC.

Add the remote device to QtCreator

To add the remote Linux device on QtCreator, use the Tools->Options menu and click on "Devices" item. At this point click on "Add" button and fill the fields using values similar to the screenshot. In particular specify a name for the device, the IP of the remote machine and a username and password that must already exist (I just created the user "andrea" on the Xubuntu machine and used the same password). I also had to set the timeout to 20 seconds, because I had some connection problems and the connection kept dropping after 10 seconds trying. To verify if everything is working fine, just click on Test button.

Add a specific Qt version

To write your application you may need a specific Qt version that is different from the one distributed by your Linux distribution. There's no problem, QtCreator let you add different Qt versions without any conflict. In my case I installed the Qt5 version distributed by Canonical Qt5 Edgers Team: https://launchpad.net/~canonical-qt5-edgers
Once it's installed, just click on "Add" button and select the qmake specific to the version you want to add (in my case it was in /opt/qt5/bin/qmake ).

Add a Qt Kit

QtCreator permits to add new Kit (development configurations) and these kits are used during project creation to specify what you want to target. In my example I added a new kit choosing an appropriate name "Qt5 Ubuntu", the device type, the actual device previously configured and finally the Qt version that we added before. With a kit I have a complete "toolchain" that allow me to write applications for a particular device, with a specific Qt version.

Putting the pieces together

At this point you just have to create a new "Qt Quick 2" application, and select the new kit you just created instead of the "Desktop" one. Please note that there is a little problem that I haven't fixed yet (but I'm working on it): if you create, for example, a project named "QtTest1" it will be deployed to the folder /opt/QtTest1/ on the remote machine. By default your user doesn't have read+write permissions for that folder so I manualy created the folder and I gave a chmod 777 on it, just for testing. There are two possible ways to fix this: you could create a specific user that has read+write permissions on /opt/ or you could modify the deployment configuration to have the app deployed to the user /home (I will investigate on this possibility and I will write something in one of the next posts).

Final thoughts

What all of this could be useful for? Well, do 2+2 and you'll easily guess ;) In the next weeks I will post more specific informations and I will update everyone with my progresses. Any comment is welcome! If you want to contribute to this you're welcome too of course.

Social Connect is a library written in Qt that allows applications to easily connect to services like Facebook and Twitter. Recently I had the opportunity to work on this library improving it and adding support for Instagram (work is still in progress but it's almost finished).

The main features of this library are:

• Out-of-the-box support for Facebook and Twitter
• Integrated authentication implementation
• Simplified common interface for all supported services
• Provides interfaces for native API calls
• Design enabling easy addition of new services e.g. LinkedIn

If you are writing an application that needs to access these services, this could be the library for you. It can be extended to support even other services like LinkedIn, Flickr etc... and I would like to invite people to contribute to the code. The library has been tested with Qt 4.8.1 on Ubuntu Linux 12.04 but it should be compatible with any other versions/platforms.

For more informations about getting started with the library, I suggest you to give a look at this page https://projects.developer.nokia.com/socialconnect/wiki/GettingStarted

If you try to install Nokia QtSDK on Ubuntu using the Nokia installer (that provides a newer version than the one distributed in Ubuntu Software Center) you could get an error like this:

(Qt_SDK_Lin32_offline_v1_1_3_en.run:3126): Gtk-CRITICAL **:
IA__gtk_widget_style_get: assertion `GTK_IS_WIDGET (widget)`
failed

to fix it, you need to run the installer with a specific parameter:

./Qt_SDK_Lin32_offline_v1_1_4_en.run -style cleanlooks

and everything should work!

SomaFM is a streaming radio with near 16 different channels, available for free. Even if it's possible to copy-paste their streaming URLs to N900 Media Player, we (me and Lorenzo Bettini) decided to create a custom application, to make channels switching easier for the end user and to be able to add more features. We decided to take advantage of the new Nokia SDK and write the application in Qt/C++. Source code is available on Gitorious and it's always updated with latest version we're working on. If someone want to test the application, it's available in extras-devel repository  ("msoma" under Multimedia section) of N900.

The UI is still in development as you can see. The application is already usable, but of course we have to work hard on the user interface. Feel free to test/use it and send us any feedback. If you want to contribute to our project (coders are welcome) please send us a patch with your code or ask us to be added to mSoma development team in Gitorious.