Thread

We use PySide6's QThread class for multi-threaded operations.

Basic QThread Usage

1. Inheriting QThread Class

from PySide6.QtCore import QThread

class WorkerThread(QThread):
    def run(self):
        # Write your execution code here
        pass

2. Defining Signals (Optional)

from PySide6.QtCore import QThread, Signal

class WorkerThread(QThread):
    progress = Signal(int)  # Signal for progress updates
    result = Signal(object)  # Signal for delivering results

    def run(self):
        # Emit signal during operation
        self.progress.emit(50)
        # Deliver operation result
        self.result.emit("Task completed")

3. Thread Usage Example

def on_finished():
    print("Operation completed")

def on_progress(value):
    print(f"Progress: {value}%")


# Create thread instance
worker = WorkerThread()

worker.finished.connect(on_finished)  # Callback when task completes

worker.progress.connect(on_progress)  # Callback for progress updates

# Start thread
worker.start()

Key Methods and Signals

QThread Basic Methods

• start(): Start thread

• quit(): Request thread termination

• wait(): Wait until thread terminates

• isRunning(): Check if thread is running

• terminate(): Force thread termination (not recommended)

Basic Signals

• started: Emitted when thread starts

• finished: Emitted when thread ends

Important Notes

1. GUI updates should only be performed on the main thread.

2. Avoid using terminate() as it forces termination without resource cleanup.

3. Proper synchronization is needed when sharing data between threads.

Example: Progress Display Operation

from PySide6.QtCore import QThread, Signal
import time

class WorkerThread(QThread):
    progress = Signal(int)

    def run(self):
        for i in range(101):
            self.progress.emit(i)
            time.sleep(0.1)  # Simulating work

# Usage example
worker = WorkerThread()
worker.progress.connect(lambda v: print(f"Progress: {v}%"))
worker.finished.connect(lambda: print("Task completed!"))
worker.start()

This guide explains the basic methods of implementing multi-threading using QThread in PySide6. In actual applications, please design and use appropriate signals and slots according to the characteristics of your tasks.