python鼠标绘图附代码

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Time : 2019/12/3 14:22
# @Author : Chen Shan
# Function :GUI programming - a naive Sketchpad tool
import os
import platform
import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class PenWidthDlg(QDialog):
    def __init__(self, parent=None):
        super(PenWidthDlg, self).__init__(parent)
        widthLabel = QLabel("宽度:")
        self.widthSpinBox = QSpinBox()
        widthLabel.setBuddy(self.widthSpinBox)
        self.widthSpinBox.setAlignment(Qt.AlignRight|Qt.AlignVCenter)
        self.widthSpinBox.setRange(0, 50)
        okButton = QPushButton("ok")
        cancelButton = QPushButton("cancle")
        layout = QGridLayout()
        layout.addWidget(widthLabel,0,0)
        layout.addWidget(self.widthSpinBox,0,1)
        layout.addWidget(okButton,1,0)
        layout.addWidget(cancelButton,1,1)
        self.setLayout(layout)
        self.setWindowTitle("宽度设置")
        okButton.clicked.connect(self.accept)
        cancelButton.clicked.connect(self.reject)
class myMainWindow(QMainWindow):
    def __init__(self,parent=None):
        super().__init__(parent)
        self.setWindowTitle("draw")
        self.pix=QPixmap()
        self.lastPoint=QPoint()
        self.endPoint=QPoint()
        #初始化参数
        self.initData()
        #清空画布
        self.initView()
        #菜单栏
        self.Menu = self.menuBar().addMenu("菜单")
        #清空
        self.ClearAction = QAction(QIcon("images/clear.png"), "清空", self)
        self.ClearAction.triggered.connect(self.initView)
        self.Menu.addAction(self.ClearAction)
        #调画笔颜色
        self.changeColor = QAction(QIcon("images/icon.png"), "颜色", self)
        self.changeColor.triggered.connect(self.showColorDialog)
        self.Menu.addAction(self.changeColor)
        #调画笔粗细
        self.changeWidth = QAction(QIcon("images/width.png"), "宽度", self)
        self.changeWidth.triggered.connect(self.showWidthDialog)
        self.Menu.addAction(self.changeWidth)
        # #右侧停靠窗口
        # logDockWidget=QDockWidget("Log",self)
        # logDockWidget.setAllowedAreas(Qt.LeftDockWidgetArea|Qt.RightDockWidgetArea)
        # self.listWidget=QListWidget()
        # logDockWidget.setWidget(self.listWidget)
        # self.addDockWidget(Qt.RightDockWidgetArea,logDockWidget)
        #各种动作
        self.fileOpenAction = QAction(QIcon("images/fileopen.png"), "&Open", self)
        self.fileOpenAction.setShortcut(QKeySequence.Open)
        self.fileOpenAction.setToolTip("Open an image.")
        self.fileOpenAction.setStatusTip("Open an image.")
        self.fileOpenAction.triggered.connect(self.fileOpen)
        self.fileSaveAction = QAction(QIcon("images/filesave.png"), "&Save", self)
        self.fileSaveAction.setShortcut(QKeySequence.Save)
        self.fileSaveAction.setToolTip("Save an image.")
        self.fileSaveAction.setStatusTip("Save an image.")
        self.fileSaveAction.triggered.connect(self.fileSaveAs)
        #工具栏
        fileToolbar = self.addToolBar("文件")
        fileToolbar.addAction(self.fileOpenAction)
        fileToolbar.addAction(self.fileSaveAction)
        editToolbar = self.addToolBar("清空")
        editToolbar.addAction(self.ClearAction)
        colorToolbar = self.addToolBar("颜色")
        colorToolbar.addAction(self.changeColor)
        widthToolbar = self.addToolBar("宽度")
        widthToolbar.addAction(self.changeWidth)
        #状态栏
        self.sizeLabel=QLabel()
        self.sizeLabel.setFrameStyle(QFrame.StyledPanel|QFrame.Sunken)
        status=self.statusBar()
        status.setSizeGripEnabled(False)
        status.addPermanentWidget(self.sizeLabel)
        status.showMessage("Ready",5000)
    def initData(self):
        self.size = QSize(1000,1040)
        self.pixmap = QPixmap(self.size)
        self.dirty = False
        self.filename = None
        self.recentFiles = []
        #新建画笔
        self.width = 5
        self.color = QColor(0, 0, 0)
        self.pen = QPen()  # 实例化画笔对象
        self.pen.setColor(self.color)  #设置画笔颜色
        self.pen = QPen(Qt.SolidLine)  #实例化画笔对象.参数：画笔样式
        self.pen.setWidth(self.width) #设置画笔粗细
        #新建绘图工具
        self.painter = QPainter(self.pixmap)
        self.painter.setPen(self.pen)
        #鼠标位置
        self.__lastPos = QPoint(0,0)#上一次鼠标位置
        self.__currentPos = QPoint(0,0)#当前的鼠标位置
        self.image = QImage()
    def initView(self):
        #设置界面的尺寸为__size
        self.Clear()
        self.imageLabel = QLabel()
        self.imageLabel.setPixmap(self.pixmap)
        self.setCentralWidget(self.imageLabel)
    def Clear(self):
        #清空画板
        self.pixmap.fill(Qt.white)
        self.update()
        self.dirty = False
    def mousePressEvent(self,event):
        #鼠标按下时，获取鼠标的当前位置保存为上一次位置
        pointX = event.globalX()
        pointY = event.globalY()
        self.__currentPos = QPoint(pointX,pointY)
        self.dirty = True
        self.__currentPos =  event.pos()
        self.__lastPos = self.__currentPos
    def mouseMoveEvent(self,event):
        #鼠标移动时，更新当前位置，并在上一个位置和当前位置间画线
        self.__currentPos =  event.pos()
        #pointX = event.globalX()
        #pointY = event.globalY()
        #self.__currentPos = QPoint(pointX,pointY)
        #画线
        #用begin和end抱起来，表示针对这个对象，就可以在pixmap有图的情况下继续画画 
        self.painter.begin(self.pixmap)
        self.painter.setPen(self.pen)
        self.painter.drawLine(self.__lastPos, self.__currentPos)
        self.__lastPos = self.__currentPos  
        self.painter.end()          
        self.update() #更新显示
        self.imageLabel.setPixmap(self.pixmap)
    #调画笔颜色
    def showColorDialog(self):
        col = QColorDialog.getColor()
        self.pen.setColor(col)
        self.painter.setPen(self.pen)
    def updateWidth(self):
        self.pen.setWidth(self.width)
        self.painter.setPen(self.pen)
    def showWidthDialog(self):
        dialog = PenWidthDlg(self)
        dialog.widthSpinBox.setValue(self.width)
        if dialog.exec_():
            self.width = dialog.widthSpinBox.value()
            self.updateWidth()
    ###########################################################
    def okToContinue(self): #警告当前图像未保存
            if self.dirty:
                reply = QMessageBox.question(self,
                        "Image Changer - Unsaved Changes",
                        "图片已被更改，请问要保存吗?",
                        QMessageBox.Yes|QMessageBox.No|QMessageBox.Cancel)
                if reply == QMessageBox.Cancel:
                    return False
                elif reply == QMessageBox.Yes:
                    return self.fileSaveAs()
            return True
    def fileOpen(self):
            if not self.okToContinue():
                  return
            dir = (os.path.dirname(self.filename)
                   if self.filename is not None else ".")
            formats = (["*.{}".format(format.data().decode("ascii").lower())
                  for format in QImageReader.supportedImageFormats()])
            fname = QFileDialog.getOpenFileName(self,
                  "Image Changer - Choose Image", dir,
                  "Image files ({})".format(" ".join(formats)))
            if fname:
                  print(fname[0])
                  self.loadFile(fname[0])
                  self.updateFileMenu()
    def loadFile(self, fname=None):
            if fname is None:
                  action = self.sender()
                  if isinstance(action, QAction):
                        fname = action.data()
                        if not self.okToContinue():
                            return
                  else:
                        return
            if fname:
                  self.filename = None
                  image = QImage(fname)
                  if image.isNull():
                        message = "Failed to read {}".format(fname)
                  else:
                        self.addRecentFile(fname)
                        self.image = QImage()
                        #self.editUnMirrorAction.setChecked(True)
                        self.image = image
                        self.filename = fname
                        self.showImage()
                        self.dirty = False
                        self.sizeLabel.setText("{} x {}".format(
                                               image.width(), image.height()))
                        message = "Loaded {}".format(os.path.basename(fname))
                  self.updateStatus(message)
    def updateStatus(self, message):
            self.statusBar().showMessage(message, 5000)
            #self.listWidget.addItem(message)
            if self.filename:
                  self.setWindowTitle("Image Changer - {}[*]".format(
                        os.path.basename(self.filename)))
            elif not self.image.isNull():
                  self.setWindowTitle("Image Changer - Unnamed[*]")
            else:
                  self.setWindowTitle("Image Changer[*]")
            self.setWindowModified(self.dirty)
    def updateFileMenu(self):
            self.Menu.clear()
            self.Menu.addAction(self.fileOpenAction)
            self.Menu.addAction(self.fileSaveAction)
            current = self.filename
            recentFiles = []
            print(self.recentFiles)
            for fname in self.recentFiles:
                if fname != current and QFile.exists(fname):
                    recentFiles.append(fname)
            if recentFiles:
                self.fileMenu.addSeparator()
                for i, fname in enumerate(recentFiles):
                    action = QAction(QIcon("images/icon.png"),
                            "&{} {}".format(i + 1, QFileInfo(
                            fname).fileName()), self)
                    action.setData(fname)
                    action.triggered.connect(lambda: self.loadFile(fname))
                    self.fileMenu.addAction(action)
    def addRecentFile(self, fname):
            if fname is None:
                  return
            if fname not in self.recentFiles:                 
                  if len(self.recentFiles) < 10:
                        self.recentFiles = [fname] + self.recentFiles
                  else:
                        self.recentFiles = [fname] + self.recentFiles[:8]
                  print(len(self.recentFiles))
    def fileSaveAs(self):
        savePath = QFileDialog.getSaveFileName(self, 'Save Your Paint', '.\\', '*.png')
        print(savePath)
        if savePath[0] == "":
            print("Save cancel")
            return
        image = self.pixmap
        print("save...")
        image.save(savePath[0])
        self.updateStatus("Saved as {}".format(savePath))
    def showImage(self, percent=None):
        if self.image.isNull():
            return
        self.pixmap = QPixmap.fromImage(self.image)
        self.imageLabel.setPixmap(self.pixmap)
app=QApplication(sys.argv)
form=myMainWindow()
form.setMinimumSize(1000,1000)
form.show()
app.exec_()