PyQt is one of the most powerful and widely used GUI frameworks in the Python language, and is based on the Python binding implementation of the Qt library. ThatModular architectureandCross-platform features(Windows, macOS, Linux) makes it an ideal choice for developing desktop applications. This article will analyze the core modules of PyQt in depth and display its application scenarios through code examples.
1. Overview of PyQt core modules
PyQt divides the Qt function into multiple submodules, each focusing on functional implementations in a specific field. The following are the main modules and their functions:
| Module name | Function description | Typical application scenarios |
|---|---|---|
| QtCore | Core non-GUI features | Signal slot, file processing, multi-threading |
| QtGui | Graphics Component Basics | Drawing, font, image processing |
| QtWidgets | UI Control Library | Window, buttons, input boxes and other controls |
| QtNetwork | Network communication | HTTP request, TCP/UDP communication |
| QtSql | Database interaction | SQL query, transaction management |
| QtMultimedia | Multimedia processing | Audio playback, video streaming processing |
| QtWebEngine | Web Rendering | Embed browser and web content display |
| QtCharts | Data visualization | Line chart, bar chart, pie chart |
2. Detailed explanation and examples of core modules
1. QtCore - Core Basic Module
Provide basic functions such asObject communication mechanism (signal and slot)、Event loopandFile processing。
Key Category:
-
QObject: Base class of all Qt objects -
QTimer: Timer -
QFile: File operation -
QThread: Multi-threaded support
Example: Timed update interface
from import QTimer, QObject, pyqtSignal
class Worker(QObject):
update_signal = pyqtSignal(str)
def __init__(self):
super().__init__()
= QTimer()
(self.update_time)
def update_time(self):
from datetime import datetime
self.update_signal.emit(().strftime("%H:%M:%S"))
def start(self):
(1000) # Triggered every second2. QtWidgets - UI Control Library
The core module for building the user interface, including40+ types of prefabricated controls。
Key Components:
-
QApplication: Apply the main loop -
QMainWindow: Main window frame -
QPushButton: Button -
QLabel: Text tags -
QLineEdit: Single line input box
Example: Create a basic window
from import QApplication, QMainWindow, QPushButton
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
("PyQt Demo")
(100, 100, 400, 300)
btn = QPushButton("Click Me", self)
(150, 150)
(self.on_click)
def on_click(self):
print("The button is clicked!")
if __name__ == "__main__":
app = QApplication([])
window = MainWindow()
()
app.exec_()3. QtGui - Graphics Processing
deal withDrawing、Font managementandImage operationbasic module.
Core functions:
-
QPainter: 2D drawing -
QFont: Font management -
QPixmap: Image processing
Example: Custom drawing
from import QWidget
from import QPainter, QColor
class Canvas(QWidget):
def paintEvent(self, event):
painter = QPainter(self)
(QColor(255, 0, 0))
(50, 50, 100, 100) # Draw a red circle4. QtNetwork - Network Communication
accomplishHTTP Request、TCP/UDP communicationand other network functions.
Example: HTTP GET Request
from import QNetworkAccessManager, QNetworkRequest
from import QUrl
class Downloader:
def __init__(self):
= QNetworkAccessManager()
(self.handle_response)
def fetch(self, url):
request = QNetworkRequest(QUrl(url))
(request)
def handle_response(self, reply):
data = ()
print(f"receive {len(data)} Byte data")5. QtSql - Database Interaction
Supports multiple databases (SQLite, MySQL, PostgreSQL, etc.)Unified interface。
Example: SQLite operation
from import QSqlDatabase, QSqlQuery
# Create a database connectiondb = ("QSQLITE")
("")
if ():
query = QSqlQuery()
query.exec_("CREATE TABLE IF NOT EXISTS users (id INTEGER PRIMARY KEY, name TEXT)")
query.exec_("INSERT INTO users (name) VALUES ('Alice')")
()6. QtWebEngine - Web Rendering
Chromium-basedModern web rendering engine。
Example: Embed browser
from import QWebEngineView
from import QMainWindow
class BrowserWindow(QMainWindow):
def __init__(self):
super().__init__()
= QWebEngineView()
()
(QUrl(""))3. Comprehensive application examples
Combining multiple modules to create a weather query application:
# Complete examples containing network requests, UI controls, and JSON parsingimport sys
import json
from import (QApplication, QWidget, QVBoxLayout,
QLineEdit, QLabel, QPushButton)
from import QNetworkAccessManager
class WeatherApp(QWidget):
def __init__(self):
super().__init__()
= QNetworkAccessManager()
(self.handle_response)
self.init_ui()
def init_ui(self):
layout = QVBoxLayout()
self.city_input = QLineEdit("Input City")
self.result_label = QLabel("Waiting for inquiry...")
btn = QPushButton("Inquiry of the weather")
(self.query_weather)
(self.city_input)
(btn)
(self.result_label)
(layout)
def query_weather(self):
city = self.city_input.text()
url = f"/{city}"
(QNetworkRequest(QUrl(url)))
def handle_response(self, reply):
data = (().data())
temp = data['main']['temp']
self.result_label.setText(f"Current temperature：{temp}°C")
if __name__ == "__main__":
app = QApplication()
window = WeatherApp()
()
(app.exec_())4. PyQt version selection suggestions
- PyQt5: Current mainstream stable version (recommended)
- PyQt6: Latest version, some APIs have been adjusted
Installation command:
pip install pyqt5 # Basic installationpip install pyqt5-tools # IncludeQt DesignerPlease help with tools
5. Recommended learning resources
Official Documentation:PyQt5 Reference Guide — PyQt Documentation v5.15.7
Qt Designer Tutorial: Visual UI Design Tools
Books "PyQt5 Rapid Development and Practical Practice"
GitHub open source project reference
This is the end of this article about the detailed explanation of PyQt of Python GUI framework. For more related content of Python GUI framework, please search for my previous articles or continue browsing the related articles below. I hope everyone will support me in the future!