Python PyQt
Windows, layouts, signals and slots, and packaging to an exe.
Key PointsQt uses signals and slots instead of callbacks — connect a widget signal to a Python method and the event loop does the rest.
Minimal Window
Every PyQt6 app is three steps: create QApplication, build the window, call app.exec(). Without the last step the window flashes and exits.
Bash
pip install PyQt6Python
import sys
from PyQt6.QtWidgets import QApplication, QLabel, QWidget, QVBoxLayout
app = QApplication(sys.argv)
win = QWidget()
win.setWindowTitle("BackendWiki")
layout = QVBoxLayout(win)
layout.addWidget(QLabel("Hello, PyQt6"))
win.resize(320, 160)
win.show()
sys.exit(app.exec())Output
# 弹出一个 320x160 的窗口，显示 Hello, PyQt6Signals and Slots
A button emits clicked; connect() wires it to your function. clicked passes a checked boolean.
Python
from PyQt6.QtWidgets import QPushButton, QLineEdit, QVBoxLayout, QWidget
class Panel(QWidget):
def __init__(self):
super().__init__()
self.input = QLineEdit(placeholderText="输入点什么")
self.btn = QPushButton("回显")
self.out = QLineEdit(readOnly=True)
lay = QVBoxLayout(self)
for w in (self.input, self.btn, self.out):
lay.addWidget(w)
self.btn.clicked.connect(self.on_click)
def on_click(self, checked=False):
self.out.setText(self.input.text().upper())Output
# 点击「回显」后，下方输入框显示大写文本Layouts
| Layout | Behaviour |
|---|---|
| QVBoxLayout | Stack vertically |
| QHBoxLayout | Stack horizontally |
| QGridLayout | Row/column grid |
| QFormLayout | Label + field rows |
Packaging
Bash
pip install pyinstaller
pyinstaller --noconsole --onefile main.py
# 产物：dist/main.exe--onefile extracts to a temp dir on every launch, so startup is slow. Use --onedir when that matters.最小窗口
PyQt6 的应用骨架永远是三步：创建 QApplication、建窗口、app.exec() 进入事件循环。少了最后一步窗口会一闪而过。
Bash
pip install PyQt6Python
import sys
from PyQt6.QtWidgets import QApplication, QLabel, QWidget, QVBoxLayout
app = QApplication(sys.argv)
win = QWidget()
win.setWindowTitle("BackendWiki")
layout = QVBoxLayout(win)
layout.addWidget(QLabel("Hello, PyQt6"))
win.resize(320, 160)
win.show()
sys.exit(app.exec())Output
# 弹出一个 320x160 的窗口，显示 Hello, PyQt6信号与槽
点击按钮会发出 clicked 信号，connect() 把它接到你的函数上。函数收到的参数由信号决定 —— clicked 会带一个 checked 布尔值。
Python
from PyQt6.QtWidgets import QPushButton, QLineEdit, QVBoxLayout, QWidget
class Panel(QWidget):
def __init__(self):
super().__init__()
self.input = QLineEdit(placeholderText="输入点什么")
self.btn = QPushButton("回显")
self.out = QLineEdit(readOnly=True)
lay = QVBoxLayout(self)
for w in (self.input, self.btn, self.out):
lay.addWidget(w)
self.btn.clicked.connect(self.on_click)
def on_click(self, checked=False):
self.out.setText(self.input.text().upper())Output
# 点击「回显」后，下方输入框显示大写文本布局
| 布局 | 行为 |
|---|---|
| QVBoxLayout | 垂直排列 |
| QHBoxLayout | 水平排列 |
| QGridLayout | 行列网格 |
| QFormLayout | 标签 + 输入行 |
打包
Bash
pip install pyinstaller
pyinstaller --noconsole --onefile main.py
# 产物：dist/main.exePyInstaller 的 onefile 模式启动慢（每次解压到临时目录）。体积和启动速度敏感时用
--onedir。