PyQt- Introduction

Understanding Qt and PyQt

What is Qt?

Qt is a Python framework that is used for developing application that can have functionalities like GUI development,networking, multimedia, databases, and more. It's also known for its platform independence which allows developers to write code once and deploy it across multiple platforms easily.

What is PyQt?

PyQt is a bidge between Python and Qt. It provides Python bindings, for the Qt toolkit. With PyQt developers can create applications that have same appearance and functionality across different operating systems, including Windows, macOS, Linux and even mobile platforms, like Android.

PyQt was developed by RiverBank Computing Ltd. The latest version of PyQt can be downloaded from its official website − riverbankcomputing.comriverbankcomputing

Features of PyQt

• Comprehensive Support for Qt − PyQt has almost 1000 classes from the Qt framework which provides access to many functionalities including GUI components, networking, databases, multimedia, and more. We can build versatile and feature-rich applications using PyQt and its comprehensive support helps developer in debugging and building.
• Cross-Platform Compatibility − PyQt supports most of the operating systems, including Windows, Linux, macOS, Android, and iOS. It ensures that applications developed with PyQt can run consistently across different platforms. This cross platform support eliminate the need for platform-specific codebases.
• Licensing Options − PyQt provides dual licencing under the Riverbank Commercial License and the GPL v3. Developers can also choose the licensing option that is best for their project requirements.You should make sure that the chosen license follows the Qt's licensing terms and conditions.
• Integration with Python Ecosystem − We can easily integrate Python library with PyQt as PyQt is build on top of Python. We can use Python's extensive libraries and tools with PyQt to increase productivity and flexibility in application development.

Components of PyQt

• Python Extension Modules − PyQt provides access to Qt functionality using the Python extension module. These modules are installed as part of the PyQt5 package and cover various aspects of Qt, including GUI components, multimedia, networking, and more.
• Qt Designer Plugins − PyQt contain plugins that extend Qt Designer which is visual design tool for building GUI's. These plugins enhance the capabilities of Qt Designer, allowing developers to create custom widgets and components.
• Utility Programs − PyQt includes various utility program that helps in streamlining the development process. Some of the utility programs include pyuic,oyrcc, pylupdate.
• DBus Support − D-Bus is message bus system for inter-process communication.This support module enables integration with the Qt event loop and provides a Qt-like interface for working with D-Bus.

Building Blocks of PyQt GUI

A brief overview of some key concepts in PyQt are as follows −

• Widgets − PyQt provides a range of built-in elements like buttons, labels, text boxes, checkboxes, radio buttons and more. These widgets act as the building blocks for creating graphical user interface (GUI) applications.
• Layouts − PyQt offers managers such as QVBoxLayout, QHBoxLayout, QGridLayout and others. These managers allow you to organize widgets within a window in a manner.
• Signals and Slots − In PyQt communication between objects is facilitated through signals and slots. Signals are emitted when specific events occur and slots are functions that respond to those signals. This mechanism enables handling of user interactions with your application.
• Event Handling − With the event handling capabilities of PyQt you can manage events like mouse clicks, key presses, window resizing and more by using event handlers.
• Dialogs − PyQt provides dialogs for tasks such as file selection displaying messages or alerts to users choosing colors from a palette or color picker tool.
• Custom Widgets − You have the flexibility to create custom widgets by either subclassing existing PyQt widgets or combining widgets together based on your requirements.