PySide6 GUI 编程（46）： 基于QThread构造常驻后台的线程

from __future__ import annotations
import sys
from datetime import datetime

from PySide6.QtCore import QThread, Signal, Slot
from PySide6.QtWidgets import QApplication, QLabel, QMainWindow, QPushButton, QVBoxLayout, QWidget

class CounterThread(QThread):
    update_count = Signal(str)  # 发送带时间戳的计数信息

    def __init__(self):
        super().__init__()
        self.running = False
        self.paused = False

    def run(self):
        count = 0
        self.running = True
        while self.running:
            if not self.paused:
                timestamp = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
                message = f"{timestamp} - Count: {count}"
                self.update_count.emit(message)
                count += 1
                self.sleep(1)

    def pause_or_resume(self):
        self.paused = not self.paused

    def stop(self):
        self.running = False
        self.paused = False


class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.counter_thread = CounterThread()
        self.start_button = QPushButton("Start", self)
        self.toggle_pause_button = QPushButton("Pause", self)
        self.stop_button = QPushButton("Stop", self)
        self.count_label = QLabel("Counter not started", self)
        self.init_ui()

    def init_ui(self):
        self.setWindowTitle("Thread Control Example")

        self.start_button.clicked.connect(self.start_thread)
        self.toggle_pause_button.clicked.connect(self.toggle_pause)
        self.stop_button.clicked.connect(self.stop_thread)

        self.toggle_pause_button.setEnabled(False)  # 初始时Pause按钮不可用

        layout = QVBoxLayout()
        layout.addWidget(self.start_button)
        layout.addWidget(self.toggle_pause_button)
        layout.addWidget(self.stop_button)
        layout.addWidget(self.count_label)

        container = QWidget()
        container.setLayout(layout)
        self.setCentralWidget(container)

        self.counter_thread.update_count.connect(self.handle_count_update)

    @Slot(str)
    def handle_count_update(self, message):
        self.count_label.setText(message)

    def start_thread(self):
        if not self.counter_thread.isRunning():
            self.counter_thread.start()
            self.toggle_pause_button.setText("Pause")
            self.toggle_pause_button.setEnabled(True)  # 启动后Pause按钮可用

    def toggle_pause(self):
        self.counter_thread.pause_or_resume()
        if self.counter_thread.paused:
            self.toggle_pause_button.setText("Resume")
        else:
            self.toggle_pause_button.setText("Pause")

    def stop_thread(self):
        self.counter_thread.stop()
        self.counter_thread.wait()  # 等待线程安全结束
        self.count_label.setText("Counter stopped")
        self.toggle_pause_button.setEnabled(False)  # 停止后Pause按钮不可用


if __name__ == "__main__":
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec())