Graphs and Charts

In the previous chapter, we learned how to retrieve data from a database using Qt's sql module. There are many ways to present this data to the users, such as displaying it in the form of tables or diagrams. In this chapter, we will learn how to do the latter—presenting data with different types of graphs and charts using Qt's charts module.

In this chapter, we will cover the following topics:

• Types of charts and graphs in Qt
• Charts and graphs implementation
• Creating the dashboard page

Since Qt 5.7, several modules that were only available for commercial users before have become free for all the open source package users, which includes the Qt Charts module. Therefore, it is considered a very new module for most Qt users who don't own the commercial license.

Do note that, unlike most of the Qt modules that are available under an LGPLv3 license, the Qt Chart module is offered under an GPLv3 license. Unlike LGPLv3, a GPLv3 license requires you to release the source code of your application, while your application must also be licensed under GPLv3. This means that you are not allowed to static-link Qt Chart with your application. It also prevents the module from being used in proprietary software.

Let's get started!