Hello, QtQuick!

Submitted by mimec on 2014-07-23

It's been a while... As usual, this means that there's been a lot going on and I simply didn't have time to write. However, I'm planning to start a new series of articles dedicated to QtQuick. It's been over 2 months since I started my adventure with QtQuick, so I have some initial observations of its strong and weak points that I would like to share.

I think that the biggest problem with QtQuick is that it's hugely undervalued. Unfortunately, there are some political reasons behind this. Major software companies try to tie developers to their platforms and platform-specific frameworks. It's no big surprise that Nokia had to get rid of Qt when it was purchased by Microsoft, even though in theory a good cross-platform framework should be a goldmine for the company who owns it. The result is that many people unduly consider Qt dead.

The reality is that QtQuick has a lot of potential. It's more powerful than HTML5 when it comes to rich, platform-independent UI, and it's supported by powerful back-end Qt modules. It's free even for commercial use, and it's quite mature and still actively developed. It also supports both mobile and desktop platforms. Of course, there are also disadvantages. First, in order to use QtQuick you need to learn QML, which is not as easy as it seems, especially when attempting to create complex applications. Second, QtQuick (and Qt in general) is a toolkit, not a framework, so you have to lay down a lot of foundation before you can start being productive developing the actual application. Finally, the documentation is quite poor, and there is not too much open source code using QtQuick that you can peak into, so it's often difficult to find any useful information about a problem you're trying to solve. Because of that, learning QtQuick requires a bit of trial and error approach, but from what I can tell so far, it's worth the effort.

Apart from the fact that QtQuick has many ready to use UI components (including the Quick Controls), there are also additional benefits from writing the application partially in QML and partially in C++. When the UI is written entirely in QML, it can be designed by people with graphical skills, who don't necessarily need to know low level programming languages like C++. It's similar to how HTML/CSS templates are created independently from PHP (or whatever) code in web applications. Also the UI of the application can be fully tested without writing a single line of C++ code, which is great for rapid design and prototyping. To make it possible, simple stubs (mock objects) for application logic can be written in QML. When using a simple MVP or MVC pattern it's also possible to easily switch views - for example between the desktop and mobile versions of the application. I will write more about it in one of the next articles.