PyQt5学习--基本窗口控件--QButton类控件

参考书籍《PyQt5 快速开发与实战》王硕 孙洋洋 著

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介绍

PyQt5按钮的基类是QAbstractButton，为抽象类，不能实例化。
常见的按钮类有：QPushButton、QToolButton、QRadioButton和QCheckBox.

代码示例

QPushButton的使用

# -*- coding: utf-8 -*-

'''
    【简介】
    PyQt5中QButton例子
'''

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *

class Form(QDialog):
    def __init__(self, parent=None):
        super(Form, self).__init__(parent)
        layout = QVBoxLayout()   #设置垂直布局

        self.btn1 = QPushButton("Button1")
        # setChenkable()：设置按钮是否已经被选中，true表示按钮将被保持已点击和释放状态
        self.btn1.setCheckable(True)
        # toggle()：在按钮之间进行切换
        self.btn1.toggle()
        # 通过lambda方式来传递额外的参数btn1，将clicked信号发送给槽函数whichbtn()
        self.btn1.clicked.connect(lambda:self.whichbtn(self.btn1) )
        self.btn1.clicked.connect(self.btnstate)
        layout.addWidget(self.btn1)

        self.btn2 = QPushButton('image')
        self.btn2.setIcon(QIcon(QPixmap("./images/python.png")))
        self.btn2.clicked.connect(lambda:self.whichbtn(self.btn2) )
        layout.addWidget(self.btn2)
        self.setLayout(layout) 

        self.btn3 = QPushButton("Disabled")
        # setEnabled()：设置按钮是否可用，false时按钮变成不可用状态，点击它不会发送信号
        self.btn3.setEnabled(False)
        layout.addWidget(self.btn3)

        self.btn4= QPushButton("&Download")
        self.btn4.setDefault(True)  #设置按钮的默认状态
        self.btn4.clicked.connect(lambda:self.whichbtn(self.btn4))
        layout.addWidget(self.btn4)
        self.setWindowTitle("Button demo")

    def btnstate(self):
        if self.btn1.isChecked():  #返回按钮的状态
            print("button pressed" ) 
        else:
            print("button released" ) 

    def whichbtn(self,btn):
        print("clicked button is " + btn.text() ) 

if __name__ == '__main__':
    app = QApplication(sys.argv)
    btnDemo = Form()
    btnDemo.show()
    sys.exit(app.exec_())

效果展示

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QRadioButton的使用

# -*- coding: utf-8 -*-

'''
    【简介】
    PyQt5中QRadio例子

'''

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *

class Radiodemo(QWidget):
    def __init__(self, parent=None):
        super(Radiodemo, self).__init__(parent)
        layout = QHBoxLayout()  #设置水平布局
        self.btn1 = QRadioButton("Button1")
        self.btn1.setChecked(True)
        self.btn1.toggled.connect(lambda:self.btnstate(self.btn1))
        layout.addWidget(self.btn1)

        self.btn2 = QRadioButton("Button2")
        self.btn2.toggled.connect(lambda:self.btnstate(self.btn2))
        layout.addWidget(self.btn2)
        self.setLayout(layout)
        self.setWindowTitle("RadioButton demo")

    def btnstate(self,btn):
        if btn.text()=="Button1":
            if btn.isChecked() == True:
                print( btn.text() + " is selected" )
            else:
                print( btn.text() + " is deselected" )

        if btn.text()=="Button2":
            if btn.isChecked()== True :
                print( btn.text() + " is selected" )
            else:
                print( btn.text() + " is deselected" )

if __name__ == '__main__':
    app = QApplication(sys.argv)
    radioDemo = Radiodemo()
    radioDemo.show()
    sys.exit(app.exec_())

效果展示

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QCheckBox的使用

# -*- coding: utf-8 -*-

'''
    【简介】
    PyQt5中 QCheckBox 例子


'''

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import Qt

class CheckBoxDemo(QWidget):

    def __init__(self, parent=None):
        super(CheckBoxDemo , self).__init__(parent)

        groupBox = QGroupBox("Checkboxes")      #设置盒子框
        groupBox.setFlat( True )

        layout = QHBoxLayout()  #设置水平布局
        self.checkBox1= QCheckBox("&Checkbox1")
        self.checkBox1.setChecked(True)
        self.checkBox1.stateChanged.connect( lambda:self.btnstate(self.checkBox1) )
        layout.addWidget(self.checkBox1)

        self.checkBox2 = QCheckBox("Checkbox2")
        self.checkBox2.toggled.connect( lambda:self.btnstate(self.checkBox2) )
        layout.addWidget(self.checkBox2)

        self.checkBox3 = QCheckBox("tristateBox")
        self.checkBox3.setTristate(True)        #设置三态复选框
        self.checkBox3.setCheckState(Qt.PartiallyChecked )  #Qt.PartiallyChecked表示复选框被半选中

        self.checkBox3.stateChanged.connect( lambda:self.btnstate(self.checkBox3) )
        layout.addWidget(self.checkBox3)

        groupBox.setLayout(layout)
        mainLayout = QVBoxLayout()      #设置垂直布局
        mainLayout.addWidget(groupBox)

        self.setLayout(mainLayout)
        self.setWindowTitle("checkbox demo")

    def btnstate(self,btn ):
        #打印复选框选中状态：0表示被选中；1表示半选中；2表示没有被选中
        chk1Status = self.checkBox1.text()+", isChecked="+  str( self.checkBox1.isChecked() ) + ', chekState=' + str(self.checkBox1.checkState())   +"\n"        
        chk2Status = self.checkBox2.text()+", isChecked="+  str( self.checkBox2.isChecked() ) + ', checkState=' + str(self.checkBox2.checkState())   +"\n"  
        chk3Status = self.checkBox3.text()+", isChecked="+  str( self.checkBox3.isChecked() ) + ', checkState=' + str(self.checkBox3.checkState())   +"\n"          
        print(chk1Status + chk2Status + chk3Status )

if __name__ == '__main__':
    app = QApplication(sys.argv)
    checkboxDemo = CheckBoxDemo()
    checkboxDemo.show()
    sys.exit(app.exec_())

效果展示

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参考资源

1.《PyQt5快速开发与实战》王硕，孙洋洋
2.《PyQt5快速开发与实战》源代码下载链接