python pyqt5 实现图片浏览

# -*- coding: utf-8 -*- from PyQt5.QtCore import Qt, QPoint, QRectF, pyqtSignal, QObject from PyQt5.QtGui import QPainter, QPixmap from PyQt5.QtWidgets import QGraphicsPixmapItem, QStyleOptionGraphicsItem, QWidget, QGraphicsItem from util.ImageUtil import MyImage class ImageWidget(QGraphicsPixmapItem): # 影像在横轴偏移量 w_offset = 0 # 影像在纵轴的偏移量 h_offset = 0 # 鼠标当前所在的像素位置 w_cur_pos = 0 h_cur_pos = 0 # 当前正在显示的影像 image = None # 信号 signal_pixel_selected = None def __init__(self, pixmap: QPixmap, image: MyImage, signal_pixel_selected): super(ImageWidget, self).__init__(pixmap) self.image = image self.pixmap = pixmap self.setAcceptDrops(True) self.m_scaleValue = 1 self.m_scaleDafault = 1 self.m_isMove = False self.m_startPos = None self.setAcceptHoverEvents(True) self.signal_pixel_selected = signal_pixel_selected def boundingRect(self): self.w_offset = int(self.pixmap.width() / 2) self.h_offset = int(self.pixmap.height() / 2) return QRectF(-self.w_offset, -self.h_offset, self.pixmap.width(), self.pixmap.height()) def paint(self, painter: QPainter, const: QStyleOptionGraphicsItem, widget: QWidget): self.setOffset(-self.w_offset, -self.h_offset) painter.drawPixmap(-self.w_offset, -self.h_offset, self.pixmap) # 将主界面的控件QGraphicsView的width和height传进本类中，并根据图像的长宽和控件的长宽的比例来使图片缩放到适合控件的大小 def setQGraphicsViewWH(self, nwidth: int, nheight: int): nImgWidth = self.pixmap.width() nImgHeight = self.pixmap.height() t_width = nwidth * 1.0 / nImgWidth t_height = nheight * 1.0 / nImgHeight if t_width > t_height: self.m_scaleDafault = t_height else: self.m_scaleDafault = t_width self.setScale(self.m_scaleDafault) self.m_scaleValue = self.m_scaleDafault # 重置图片大小 def resetItemPos(self): # 缩放比例回到一开始的自适应比例 self.m_scaleValue = self.m_scaleDafault # 缩放到一开始的自适应大小 self.setScale(self.m_scaleDafault) self.setPos(0, 0) def getScaleValue(self): return self.m_scaleValue # 鼠标点击事件 def mousePressEvent(self, event): print("鼠标点击事件 x=%d y=%d" % (event.pos().x(), event.pos().y())) if event.buttons() == Qt.LeftButton: # 左键按下 self.m_startPos = event.pos() self.m_isMove = True elif event.buttons() == Qt.RightButton: # 右键按下 print("单击鼠标右键") elif event.buttons() == Qt.MidButton: # 中键按下 print("单击鼠标中键") '''滚轮滚动事件''' def wheelEvent(self, event): if event.delta() > 0 and self.m_scaleValue >= 1000: return elif event.delta() < 0 and self.m_scaleValue <= 0.01: return else: angle = event.delta() # 获取当前鼠标相对于view的位置 pos = event.pos() qrealOriginScale = self.m_scaleValue if angle > 0: self.m_scaleValue *= 1.1 else: # 滚轮下滚 self.m_scaleValue *= 0.9 self.setScale(self.m_scaleValue) # 使图片缩放的效果看起来像是以鼠标所在点为中心进行缩放的 if angle > 0: self.moveBy(-pos.x() * qrealOriginScale * 0.1, -pos.y() * qrealOriginScale * 0.1) else: # 滚轮下滚 self.moveBy(pos.x() * qrealOriginScale * 0.1, pos.y() * qrealOriginScale * 0.1) '''鼠标双击事件(单击)''' def mouseDoubleClickEvent(self, event): self.resetItemPos() '''鼠标键释放事件''' def mouseReleaseEvent(self, event): self.m_isMove = False '''鼠标移动事件''' def mouseMoveEvent(self, event): if self.m_isMove: point: QPoint = (event.pos() - self.m_startPos) * self.m_scaleValue self.moveBy(point.x(), point.y()) def hoverMoveEvent(self, event): pos = event.pos() self.w_cur_pos = int(pos.x() + self.w_offset) self.h_cur_pos = int(pos.y() + self.h_offset) info = self.image.getPointInfo(self.h_cur_pos, self.w_cur_pos) print("鼠标悬停%d,%d" % (pos.x() + self.w_offset, pos.y() + self.h_offset)) print("像素信息 %s" % info) self.signal_pixel_selected.emit(info, 5000)