Question

我已经制作了一个自定义QGraphicsView，并将其作为小部件添加到使用Qt Designer创建的应用程序表单中。包括单击鼠标在内，一切似乎都可以正常工作。进行绘制的方法被调用，但是我很难在屏幕上进行实际的重新绘制。我尝试创建paintEvent方法的副本并调用mouseEvent方法。我也尝试过直接调用paintEvent。我似乎无法用mouseEvent重新绘制它。这是代码：

import sys
from PySide2 import QtCore, QtGui, QtWidgets
from PyQt5.QtWidgets import QFileDialog
from PySide2.QtUiTools import QUiLoader
from PySide2.QtWidgets import QApplication, QPushButton, QLineEdit, QAction, QSlider
from PySide2.QtWidgets import QListWidget, QTabWidget, QGraphicsView, QGraphicsScene
from PySide2.QtWidgets import QSpinBox, QWidget, QDialog, QVBoxLayout
from PySide2.QtGui import QPixmap, QImage, QMatrix, QPainter, QColor
from PySide2.QtGui import QMouseEvent, QCursor, QPaintEvent
from PySide2.QtCore import QFile, QObject, SIGNAL

import cv2
import numpy as np
import math

class Display_Pixels(QGraphicsView):

    def __init__(self, parent=None):
        QGraphicsView.__init__(self, parent=parent)
        #super().__init__()
        self.initUI()
        self.img = cv2.imread('roi.jpg')

    def initUI(self):      
        #self.setGeometry(100, 100, 450, 450)
        #self.setWindowTitle('By Pixel')
        #self.setMouseTracking(True)
        #self.show()
        res = 40 
        self.grid = np.array([ [-1] * res  for n in range(res)]) # list comprehension
        #print(self.grid.shape)


    def paintEvent(self, e):
        qp = QPainter()
        qp.begin(self.viewport())
        self.drawRectangles(qp)
        qp.end()

    def mousePaintEvent(self):
        qp = QPainter()
        qp.begin(self.viewport())
        self.drawRectangles(qp)
        qp.end()

    def drawRectangles(self, qp, w = 20):
        print("Drawing")
        mode = 0
        x,y = 0,0 # starting position
        lr = 20
        hr = 35
        col = QColor(0, 0, 0)
        col.setNamedColor('#d4d4d4')
        qp.setPen(col)
        #print(self.img.shape)

        for g_row, img_row in zip(self.grid, self.img):
            #print(img_row.shape)
            for g_col, img_col in zip(g_row, img_row):
                r, g, b = (img_col[0], img_col[1], img_col[2])
                #print(r,g,b)

                if g_col == 1:
                    if mode == 0:
                        r = int(math.log(r+1)*lr)
                        g = int(math.log(g+1)*hr)
                        b = int(math.log(b+1)*lr)
                    elif mode == 1:
                        if r+50 <= 220: r = r+50
                        if g+80 <= 255: g = g+80
                        if b+50 <= 220: b = b+50
                    else:
                        if r+70 <= 220: r = r+70
                        if g+140 <= 255: g = g+140
                        if b+70 <= 220: b = b+70

                    qp.setBrush(QColor(r, g, b))
                    qp.drawRect(x, y, w, w)
                else:
                    qp.setBrush(QColor(r, g, b))
                    qp.drawRect(x, y, w, w)

                #qp.setBrush(QColor(200, 0, 0))
                #qp.drawRect(x, y, w, w)
                x = x + w  # move right
            y = y + w # move down
            x = 0 # rest to left edge


    def mousePressEvent(self, QMouseEvent):
        w = 16.0

        #print("MOUSE:")
        #print('(', int(QMouseEvent.x()/w), ', ', int(QMouseEvent.y()/w), ')')
        #print (QMouseEvent.pos())
        x = float(QMouseEvent.x())
        y = float(QMouseEvent.y())
        self.grid[int(y/w)][int(x/w)] = -1 * self.grid[int(y/w)][int(x/w)]
        #print(img[int(y/w), int(x/w), :])
        self.paintEvent(QPaintEvent)
        #self.mousePaintEvent()
        self.update()
        self.repaint()      

if __name__ == '__main__':
    app = QApplication.instance()
    if app is None: 
        app = QApplication(sys.argv)
    px = Display_Pixels()
    px.show()
    sys.exit(app.exec_())

Answer 1

您不应直接调用paintEvent方法，创建具有相似名称的方法不会被神奇地调用。您必须调用update()的{{1}}方法。

viewport()

获取Qt小部件以更新使用Qt Designer创建的Qt表单内的鼠标事件

1 个答案: