The data received from the user through the GUI can be directly processed by making use of simple variables, and the processed data can be displayed through variables only. But to keep the data in a structured format and get the benefits of OOP, we will learn to keep data in the form of classes. That is, the data accessed by the user through the GUI can be assigned to the class variables, processed, and displayed through class methods.
Let's create an application that will prompt the user to enter a name and, on clicking the push button after entering a name, the application will display a hello message along with the entered name. The name entered by the user will be assigned to a class variable and the hello message will also be generated by invoking the class method of the class.