【实例简介】

【实例截图】

【核心代码】

'''

Created on 2018年8月8日

@author: Freedom

'''

from PyQt5.Qt import QWidget, QColor, QPixmap, QIcon, QSize, QCheckBox

from PyQt5.QtWidgets import QHBoxLayout, QVBoxLayout, QPushButton, QSplitter,\

QComboBox, QLabel, QSpinBox, QFileDialog

from PaintBoard import PaintBoard

class MainWidget(QWidget):

def __init__(self, Parent=None):

'''

Constructor

'''

super().__init__(Parent)

self.__InitData() #先初始化数据，再初始化界面

self.__InitView()

def __InitData(self):

'''

初始化成员变量

'''

self.__paintBoard = PaintBoard(self)

self.__colorList = QColor.colorNames() #获取颜色列表(字符串类型)

def __InitView(self):

'''

初始化界面

'''

self.setFixedSize(640,480)

self.setWindowTitle("PaintBoard Example PyQt5")

main_layout = QHBoxLayout(self) #新建一个水平布局作为本窗体的主布局

main_layout.setSpacing(10) #设置主布局内边距以及控件间距为10px

main_layout.addWidget(self.__paintBoard) #在主界面左侧放置画板

sub_layout = QVBoxLayout() #新建垂直子布局用于放置按键

sub_layout.setContentsMargins(10, 10, 10, 10) #设置此子布局和内部控件的间距为10px

self.__btn_Clear = QPushButton("清空画板")

self.__btn_Clear.setParent(self) #设置父对象为本界面

self.__btn_Clear.clicked.connect(self.__paintBoard.Clear) #将按键按下信号与画板清空函数相关联

sub_layout.addWidget(self.__btn_Clear)

self.__btn_Quit = QPushButton("退出")

self.__btn_Quit.setParent(self) #设置父对象为本界面

self.__btn_Quit.clicked.connect(self.Quit)

sub_layout.addWidget(self.__btn_Quit)

self.__btn_Save = QPushButton("保存作品")

self.__btn_Save.setParent(self)

self.__btn_Save.clicked.connect(self.on_btn_Save_Clicked)

sub_layout.addWidget(self.__btn_Save)

self.__cbtn_Eraser = QCheckBox(" 使用橡皮擦")

self.__cbtn_Eraser.setParent(self)

self.__cbtn_Eraser.clicked.connect(self.on_cbtn_Eraser_clicked)

sub_layout.addWidget(self.__cbtn_Eraser)

splitter = QSplitter(self) #占位符

sub_layout.addWidget(splitter)

self.__label_penThickness = QLabel(self)

self.__label_penThickness.setText("画笔粗细")

self.__label_penThickness.setFixedHeight(20)

sub_layout.addWidget(self.__label_penThickness)

self.__spinBox_penThickness = QSpinBox(self)

self.__spinBox_penThickness.setMaximum(20)

self.__spinBox_penThickness.setMinimum(2)

self.__spinBox_penThickness.setValue(10) #默认粗细为10

self.__spinBox_penThickness.setSingleStep(2) #最小变化值为1

self.__spinBox_penThickness.valueChanged.connect(self.on_PenThicknessChange)#关联spinBox值变化信号和函数on_PenThicknessChange

sub_layout.addWidget(self.__spinBox_penThickness)

self.__label_penColor = QLabel(self)

self.__label_penColor.setText("画笔颜色")

self.__label_penColor.setFixedHeight(20)

sub_layout.addWidget(self.__label_penColor)

self.__comboBox_penColor = QComboBox(self)

self.__fillColorList(self.__comboBox_penColor) #用各种颜色填充下拉列表

self.__comboBox_penColor.currentIndexChanged.connect(self.on_PenColorChange) #关联下拉列表的当前索引变更信号与函数on_PenColorChange

sub_layout.addWidget(self.__comboBox_penColor)

main_layout.addLayout(sub_layout) #将子布局加入主布局

def __fillColorList(self, comboBox):

index_black = 0

index = 0

for color in self.__colorList:

if color == "black":

index_black = index

index = 1

pix = QPixmap(70,20)

pix.fill(QColor(color))

comboBox.addItem(QIcon(pix),None)

comboBox.setIconSize(QSize(70,20))

comboBox.setSizeAdjustPolicy(QComboBox.AdjustToContents)

comboBox.setCurrentIndex(index_black)

def on_PenColorChange(self):

color_index = self.__comboBox_penColor.currentIndex()

color_str = self.__colorList[color_index]

self.__paintBoard.ChangePenColor(color_str)

def on_PenThicknessChange(self):

penThickness = self.__spinBox_penThickness.value()

self.__paintBoard.ChangePenThickness(penThickness)

def on_btn_Save_Clicked(self):

savePath = QFileDialog.getSaveFileName(self, 'Save Your Paint', '.\\', '*.png')

print(savePath)

if savePath[0] == "":

print("Save cancel")

return

image = self.__paintBoard.GetContentAsQImage()

image.save(savePath[0])

def on_cbtn_Eraser_clicked(self):

if self.__cbtn_Eraser.isChecked():

self.__paintBoard.EraserMode = True #进入橡皮擦模式

else:

self.__paintBoard.EraserMode = False #退出橡皮擦模式

def Quit(self):

self.close()