Qt Signals & Slots: How they work

2016-12-07 Programming Qt Tutorials Niclas Roßberger

The one thing that confuses the most people in the beginning is the Signal & Slot mechanism of Qt. But it’s actually not that difficult to understand. In general Signals & Slots are used to loosely connect classes. Illustrated by the keyword emit, Signals are used to broadcast a message to all connected Slots. If no Slots are connected, the message “is lost in the wild”. So a connection between Signals & Slots is like a TCP/IP connection with a few exceptions, but this metaphor will help you to get the principle. A Signal is an outgoing port and a Slot is an input only port and a Signal can be connected to multiple Slots.

Should I use Qt containers or the std ones?

2016-11-02 Programming Qt Niclas Roßberger

If you come from plain vanilla C++, you only know the C++ Standard Library with its containers like std::vector. If you know how to use them, you can accomplish your tasks pretty fast. But if you’re coming from another language, the naming might be a bit odd. The Qt containers offer both, C++ style and Java style naming of methods. So coming from another language the Qt one’s might be easier to use.

Why I love the Qt framework

2016-10-15 Programming Qt Niclas Roßberger

Everyone that knows me, knows that I love the Qt framework. Before I started programming in C++, Java was my primary programming language. I love the generics (yes, some of you will hate me for that opinion right now) and reflection. During my Java-time I used them very often to increase reusability. But while studying we had to learn C++ and I hated it in the beginning. It felt so old and so stiff compared to Java. Continue reading

Writing a basic Qt project with Qt Creator

2016-10-10 Programming Qt Tutorials Niclas Roßberger

I’m assuming you are already able to program and at least had a look at C++. For example I won’t explain why int main(int argc, char *argv[]) is in the C++ source code.

If you create a “Qt Console Application” you will have the following code:

How to start with Qt?

2016-10-07 Programming Qt Tutorials Niclas Roßberger

In this series I’ll give you a starting point on working with Qt. Like I mentioned in Why I love the Qt framework I had a hard time at the beginning. I want to give you an easier start with this awesome peace of technology. This page will serve as an index for the whole series of tutorials and explanations. As more posts follow this page will be updated. I know there are plenty of tutorials on Qt, but maybe I’ll explain some things in a way you understand better. Continue reading