Developer Adventure

I would like to share with you interesting article about QT 5.2 changes, integration with mobile platform and preditcions of future of QT framework. You can find this article here: http://meetingcpp.com/index.php/br/items/a-look-at-qt52.html Enjoy!

Today I would like to show you optimal way of using foreach QT algorithm . I will show you why we should pass elements of foreach algorithm by const reference instead of passing them by value. Let me explain it on the below example: Output of this example is: In point I we are creating 3 objects of MyClass class and push them to myClasses QList element. In point II we are using QT foreach algorithm to invoke getValue() method for each object from myClasses list. As you can see on output text for that part of code we are invoking copy constructor before and destructor after invoking getValue() function. It is because we are passing each myClasses list element to foreach algorithm by value. Therefore we are copying that element at the beginning of foreach loop step and removing them (destructing) at the end. This is inefficient solution, especially when class of object being copied is big. It decreases performance. of our application. Solution for that i...

This is first article describing some aspects of programming with Qt framework. I am going to focus on most important basic feature of Qt framework: signal-slot mechanism . At the beginning take a look on below QT code: Output of that code is this window: This quick code is something like "Hello world" of Qt programming. Let's take a detailed look on the code. In point I we are declaring QApplication object which will contain indefinite loop which will be invoked after program starts in order to wait for user interactions. We can also analyse command line input parameters in this line, but we are not doing it because we do not have any input parameters for our application. In point II we are declaring QPushButton object which will be the only object of our application. As only parameter of our definition we are putting text which should be displayed on our button - "Hello World" . Point III is key point of this example. It presents basic ...