Python PyQt5 在 QThread 上为 QPushButton 加载图像

Question

所以我有这个 UI 可以加载很多按钮，所有按钮都有图像，问题是，它需要很长时间，所以我试着把它放到 QThread 中，我让它工作了, 但没有速度差异，所以我尝试了不同的解决方案，但现在线程无法启动。

代码：

import sys
import os
from PyQt5 import *
from PyQt5.QtGui import *
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
from PyQt5 import QtCore, QtGui, QtPrintSupport, QtWidgets, uic

# I've tried using a QThread for this, but it still took the same amount of time.
class LoadImageThumbnailshread(QThread):
    def __init__(self, listButtons, listPaths):
        QThread.__init__(self)
        self.listButtons = listButtons
        self.listPaths = listPaths

    def run(self):
        self.process_images_Thread()

    def process_images_Thread(self):
        for i, j in enumerate(self.listButtons):
            j.setIcon(QIcon(self.listPaths[i]))
            j.setIconSize(QSize(150-6, 60-6))


class App(QDialog):

    def __init__(self):
        super().__init__()
        self.title = 'PyQt5 layout - pythonspot.com'
        self.left = 10
        self.top = 10
        self.width = 320
        self.height = 100
        self.images_path = []
        self.button_images = []
        self.initUI()

    def initUI(self):
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top, self.width, self.height)

        self.createGridLayout()

        windowLayout = QVBoxLayout()
        windowLayout.addWidget(self.horizontalGroupBox)
        self.setLayout(windowLayout)

        self.show()

    def createGridLayout(self):
        self.horizontalGroupBox = QGroupBox("Grid")
        layout = QGridLayout()
        layout.setColumnStretch(1, 4)
        layout.setColumnStretch(2, 4)

        for i in range(100):
            self.btnImage = QPushButton()
            self.btnImage.setObjectName('btnImage')
            self.images_path.append(os.path.dirname(
                os.path.abspath(__file__)) + 'view.png')

            # ! I have also tried using Pixmaps with Clickable labels, but it made no diffrence.
            # pixmap = QPixmap(os.path.dirname(os.path.abspath(__file__)) + image_locations[i])
            # pixmap = pixmap.scaled(60, 300, Qt.KeepAspectRatio, Qt.FastTransformation)
            # self.btnImage.setPixmap(pixmap)

            # ! Enableing this loads the images, but very slowly
            # self.btnImage.setIcon(QIcon(os.path.dirname(os.path.abspath(__file__)) + '/view.png'))
            # self.btnImage.setIconSize(QSize(150-6, 60-6))
            self.button_images.append(self.btnImage)
            layout.addWidget(self.btnImage, i, 0)

        # ! This starts the QThread
        converter = LoadImageThumbnailshread(
            self.button_images, self.images_path)
        converter.start()
        self.horizontalGroupBox.setLayout(layout)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = App()
    sys.exit(app.exec_())

因此，为了解释更多我想要的内容，我想在 UI 加载后启动 QThread，QThread 会将所有图像加载到每个纽扣。问题是：它现在不工作。

我遇到的另一个问题是，当我收到 QThread 时，UI 等待它完成，然后所有内容突然弹出。我希望 QThread 完全独立且漂亮，如果您愿意，请看所有图片一张一张地加载。

Answer 1

线程不用于加速任何任务！！！而是执行不阻塞任何线程的任务。鉴于上述情况，如果我有 n 个“任务”并且每个任务都在“n”个线程中执行，那么总执行时间将为 1 个任务，也就是说，没有任务被加速但任务被重新分配。结论：如果你想加速任务，那么线程不是默认选项，因为它取决于应用程序。

另一方面，加载图片并不耗时，但是有很多耗时少的任务加起来相当于一个耗时多的任务，不幸的是那个任务无法执行另一个线程或进程，因为 GUI 的元素不是 thread-safe.

一个解决方法是每 T 秒加载一小组 n 个元素，这样整个任务将被分配并且用户不会观察到任何滞后影响。

import os
import sys

from PyQt5.QtCore import QSize, QTimer
from PyQt5.QtGui import QIcon
from PyQt5.QtWidgets import (
    QApplication,
    QDialog,
    QGridLayout,
    QGroupBox,
    QPushButton,
    QVBoxLayout,
)


class App(QDialog):
    def __init__(self):
        super().__init__()
        self.title = "PyQt5 layout - pythonspot.com"
        self.left = 10
        self.top = 10
        self.width = 320
        self.height = 100
        self.images_path = []
        self.button_images = []
        self.initUI()

    def initUI(self):
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top, self.width, self.height)

        self.createGridLayout()

        windowLayout = QVBoxLayout(self)
        windowLayout.addWidget(self.horizontalGroupBox)

        self._iter = iter(range(100))
        self._timer = QTimer(interval=10, timeout=self.lazy_loading)
        self._timer.start()

    def createGridLayout(self):
        self.horizontalGroupBox = QGroupBox("Grid")
        self.grid_layout = QGridLayout()
        self.grid_layout.setColumnStretch(1, 4)
        self.grid_layout.setColumnStretch(2, 4)
        self.horizontalGroupBox.setLayout(self.grid_layout)

    def lazy_loading(self):
        try:
            i = next(self._iter)
        except StopIteration:
            self._timer.stop()
        else:
            btn = QPushButton()
            image_path = os.path.join(os.path.abspath(__file__), "view.png")
            btn.setIcon(QIcon(image_path))
            btn.setIconSize(QSize(150 - 6, 60 - 6))
            self.grid_layout.addWidget(btn, i, 0)


if __name__ == "__main__":
    app = QApplication(sys.argv)
    ex = App()
    ex.show()
    sys.exit(app.exec_())

Python PyQt5 在 QThread 上为 QPushButton 加载图像

Python PyQt5 load Image for QPushButton on QThread

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pyqt5