showpicture.py

from PyQt5.QtCore import *from PyQt5.QtWidgets import *from PyQt5.QtGui import *import sysclass MyWidget(QWidget):    def __init__(self, parent = None):        super().__init__(parent)        self.setWindowTitle(self.tr('显示图片'))        self.resize(500,400)        self.label = QLabel(self)        self.label.setFrameShape(QFrame.Box)        self.label.setAlignment(Qt.AlignCenter)        img = QImage()        if img.load('meixi.jpg'):            self.label.setGeometry(0,0,400,300)            width = img.width()            height = img.height()            if width/400 >= height/300:                ratio = width/400            else:                ratio = height/300            new_width = width/ratio            new_height = height/ratio            new_img = img.scaled(new_width,new_height,Qt.KeepAspectRatio)            print(new_img)            self.label.setPixmap(QPixmap.fromImage(new_img))if __name__ == '__main__':    app = QApplication(sys.argv)    widget = MyWidget()    widget.show()    #print(widget.children())    sys.exit(app.exec_())