Using Qt Creator with Python for Ubuntu App Development

Python is a versatile language known for its simplicity and readability, which makes it a popular choice for developers. Coupled with the powerful Qt Creator, it can be used to develop robust applications for Ubuntu. This article will guide you through the process of using Qt Creator with Python for Ubuntu app development.

What is Qt Creator?

Qt Creator is a cross-platform integrated development environment (IDE) tailored for Qt development. It is primarily designed for C++ development, but also has support for Python.

PyQt and PySide

Before we delve into the process, let’s understand the two popular Qt-Python bindings: PyQt and PySide.

• PyQt is a set of Python bindings for the Qt libraries. It is dual-licensed under the GPL and commercial licenses.
• PySide is another set of Python bindings for Qt libraries, licensed under the LGPL.

Both bindings provide access to the Qt framework, allowing you to develop Qt applications using Python.

Step 1: Install Qt Creator

The first step is to download and install Qt Creator from the official Qt website.

Step 2: Install PyQt or PySide

Choose either PyQt or PySide as your Qt-Python binding. Install the chosen binding by following the installation instructions provided on their respective websites:

• PyQt
• PySide

Step 3: Designing the Interface

Qt Creator comes with a form building tool, Qt Designer, that allows you to visually create and arrange widgets for your application’s interface. Save the interface file with a .ui extension.

Step 4: Convert the Interface File

The next step is to convert the .ui file into a Python file. This can be done using the pyuic4 command for PyQt or pyside-uic command for PySide. This step generates the necessary code to create and populate the user interface.

Here’s an example command for PyQt:

pyuic4 editorFrame.ui -o editorFrame.py

In this command, editorFrame.ui is the input file and editorFrame.py is the output file. The -o option specifies the output file.

Step 5: Import the Converted File

In your main Python file, import the converted Python file generated from the interface file. This file will contain the necessary code to set up the user interface. Here’s an example import statement:

from editorFrame import Ui_MainWindow

Step 6: Set Up the Main Class

Create a main class that inherits from the appropriate Qt class (e.g., QMainWindow). In the constructor, create an instance of the imported class (Ui_MainWindow) and call its setupUi method, passing in self as the argument. This method sets up the user interface.

Here’s an example:

class Editor(QtGui.QMainWindow):
 def __init__(self):
 super(Editor, self).__init__()
 self.ui = Ui_MainWindow()
 self.ui.setupUi(self)
 self.show()

Step 7: Run the Application

In the main function, create an instance of your main class and start the Qt event loop. Here’s an example:

def main():
 app = QtGui.QApplication(sys.argv)
 ex = Editor()
 sys.exit(app.exec_())

In this function, QApplication(sys.argv) is used to create a new Qt application. ex = Editor() creates an instance of our main class, and sys.exit(app.exec_()) starts the Qt event loop.

Step 8: Execute the Script

Add the following code at the end of your script to ensure it is only executed if it is the main script being run:

if __name__ == '__main__':
 main()

This code checks if the script is being run directly or being imported as a module. If it is being run directly, it calls the main function.

Conclusion

With these steps, you can use Qt Creator as an IDE for developing Qt applications using Python on Ubuntu. Remember to install the necessary dependencies and choose either PyQt or PySide as your Qt-Python binding. The process may seem complex at first, but with practice, it becomes intuitive and efficient. Happy coding!

if __name__ == '__main__':
 main()