pyqt5 graphicview 加载图片后点击图片后，在周围框选一个100*100的红色透明矩形，并返回矩形坐标 完整代码

以下是一个使用 PyQt5 的 QGraphicsView 控件加载图片，并在点击图片后绘制一个红色透明矩形的示例代码。当用户点击矩形时，程序会将矩形的坐标打印出来。

import sys
from PyQt5.QtCore import Qt, QRectF
from PyQt5.QtGui import QPixmap, QColor, QPainter, QPen, QBrush
from PyQt5.QtWidgets import QApplication, QGraphicsScene, QGraphicsView


class ImageViewer(QGraphicsView):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.scene = QGraphicsScene(self)
        self.setScene(self.scene)
        self.setSceneRect(0, 0, self.width(), self.height())
        self.setRenderHint(QPainter.Antialiasing)
        self.setRenderHint(QPainter.SmoothPixmapTransform)
        self.image_item = None
        self.rect_item = None
        self.rect_start_pos = None

    def load_image(self, filename):
        pixmap = QPixmap(filename)
        self.scene.clear()
        self.image_item = self.scene.addPixmap(pixmap)
        self.setSceneRect(QRectF(pixmap.rect()))

    def mousePressEvent(self, event):
        if event.button() == Qt.LeftButton and self.image_item is not None:
            self.rect_start_pos = event.pos()
            self.rect_item = self.scene.addRect(0, 0, 0, 0, QPen(Qt.red), QBrush(QColor(255, 0, 0, 50)))

    def mouseMoveEvent(self, event):
        if self.rect_item is not None and self.rect_start_pos is not None:
            rect = QRectF(self.rect_start_pos, event.pos()).normalized()
            self.rect_item.setRect(rect)

    def mouseReleaseEvent(self, event):
        if self.rect_item is not None and self.rect_start_pos is not None:
            rect = QRectF(self.rect_start_pos, event.pos()).normalized()
            if rect.width() > 100 and rect.height() > 100:
                print(rect.x(), rect.y(), rect.width(), rect.height())
            self.rect_item = None
            self.rect_start_pos = None


if __name__ == '__main__':
    app = QApplication(sys.argv)
    viewer = ImageViewer()
    viewer.load_image('test.jpg')
    viewer.show()
    sys.exit(app.exec_())

在这个例子中，我们使用了 QGraphicsView 控件来显示图片，并使用 QGraphicsScene 控件来管理所有的图形项。当用户点击鼠标左键时，程序会创建一个矩形图形项，并使用鼠标移动事件来更新矩形的大小和位置。当用户释放鼠标左键时，程序会检查矩形是否符合要求（宽度和高度都大于 100），并打印矩形的坐标。