Qt Certification is handled by PearsonVue. You can search there for Vienna, a quick look showed 5 possibilities.
Like other certificates, they prove that you have reached a certain degree of knowledge in the understanding and the use of the framework which increase your value when looking for a job requiring Qt as part of your CV.
@Hareen-Laks@dheerendra If you are developing an application for Mobile Devices, there will be many different Operating Systems like one device will be having Android, one will be having iOS etc.., So you need to write code specific to each Operating System which is time consuming and it is very costly. So there arises a thought that "Can we write code once and use on different Operating Systems..?" The answer is YES, with the help of Cross platform libraries. And Qt Framework is the one which provides Cross Platform Libraries for developing Apllications across different sets of Platforms.
I'm not sure I understand that phrase correctly. However the use of QVariant to transfer complex data from one point to another comes to mind. And you can use QVariant based container when you want to pass heterogeneous data from one class to another.
[quote author="pkj__" date="1377160932"]How long are the qt certification valid for? Is it like CCNA which expire after a year?
No they do not expire. But they have a version number though which can be used to determine how up-to-date your certification is.
[quote author="pkj__" date="1377160932"]
And I believe there is a significant waiting time till when printed certificates are delivered. Do we get a mail in the meantime from digia, so that I can quote the same in my CV??[/quote]
Indeed, before you receive the printed certificate you have to wait a ~2-3 months.
AFAIR you just receive a confirmation that you passed the exam (printed on ordinary whitepaper).
Having some insights in "certification" as such, I can tell you, that no certification program in general is thought to fill a lack of experience. If you are looking for a long term employment, this is one more reason to avoid all "tricks" which can undermine the trust on both sides. Generally, a good hiring manager prefers getting people with more commitment, loyalty and a clear will to become better than "high-fly" experts who will soon jump of the board on the next convenient occasion...
Yes, a Qt Certification proof is yet another item you can put on your CV in addition to all the projects you have done in the past. But! This is more like an external, and independent reference for your skills, but not a skill on its own!