第三课 PyQt5中QLabel标签、QLineEdit、QTextEdit等输入控件使用

第三课 PyQt5QLabel标签、QLineEdit、QTextEdit等输入控件使用

tags:

• python
• 网易云课堂

categories:

• pyqt5
• QLabel控件
• QLineEdit控件
• QTextEdit控件

第一节 QLabel控件使用

1. QLabel基本用法

1. setAlignment()：设置文本的对齐方式
2. setIndent()：设置文本缩进
3. text()：获取文本内容
4. setBuddy()：设置伙伴关系
5. setText()：设置文本内容
6. selectedText()：返回所选择的字符
7. setWordWrap()：设置是否允许换行
8. QLabel常用的信号（事件）：
   1. 当鼠标滑过QLabel控件时触发：linkHovered
   2. 当鼠标单击QLabel控件时触发：linkActivated

import sys
from PyQt5.QtWidgets import QVBoxLayout, QMainWindow, QApplication, QLabel, QWidget
from PyQt5.QtGui import QPixmap, QPalette
# Qt常量
from PyQt5.QtCore import Qt


class QLabelDemo(QWidget):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        label1 = QLabel(self)
        label2 = QLabel(self)
        label3 = QLabel(self)
        label4 = QLabel(self)

        label1.setText("<font color=yellow>这是一个文本标签.</font>")
        label1.setAutoFillBackground(True)
        # QPalette(调色板)类相当于对话框或控件的调色板，它管理着控件或窗体的所有颜色信息。
        palette = QPalette()
        palette.setColor(QPalette.Window, Qt.blue)  # 设置背景色
        label1.setPalette(palette)
        label1.setAlignment(Qt.AlignCenter)

        label2.setText("<a href='#'>欢迎使用Python  GUI程序</a>")

        label3.setAlignment(Qt.AlignCenter)

        label3.setToolTip('这是一个图片标签')

        label3.setPixmap(QPixmap("./images/python.jpg"))
        # 如果设为True，用浏览器打开网页，如果设为False，调用槽函数
        label4.setOpenExternalLinks(True)

        label4.setText("<a href='https://item.jd.com/12417265.html'>感谢关注《Python从菜鸟到高手》</a>")

        label4.setAlignment(Qt.AlignRight)

        label4.setToolTip('这是一个超级链接')

        vbox = QVBoxLayout()

        vbox.addWidget(label1)
        vbox.addWidget(label2)
        vbox.addWidget(label3)
        vbox.addWidget(label4)

        label2.linkHovered.connect(self.linkHovered)

        label4.linkActivated.connect(self.linkClicked)

        self.setLayout(vbox)
        self.setWindowTitle('QLabel控件演示')

    def linkHovered(self):
        print('当鼠标滑过label2标签时，触发事件')

    def linkClicked(self):
        print('当鼠标单击label4标签时，触发事件')


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

2. QLabel的伙伴关系

1. &符号后面就是我们的热键：nameLabel = QLabel(’&Name’, self)
2. nameLineEdit = QLineEdit(self)
3. 设置伙伴控件：nameLabel.setBuddy(nameLineEdit)
4. mainLayout.addWidget(控件对象,rowIndex,columnIndex,row,column)

from PyQt5.QtWidgets import *
import sys


class QLabelBuddy(QDialog):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle('QLabel与伙伴控件')

        nameLabel = QLabel('&Name', self)
        nameLineEdit = QLineEdit(self)
        # 设置伙伴控件
        nameLabel.setBuddy(nameLineEdit)

        passwordLabel = QLabel('&Password', self)
        passwordLineEdit = QLineEdit(self)
        # 设置伙伴控件
        passwordLabel.setBuddy(passwordLineEdit)

        btnOK = QPushButton('&OK')
        btnCancel = QPushButton('&Cancel')
        # 栅格布局
        mainLayout = QGridLayout(self)
        # 第一行第一列
        mainLayout.addWidget(nameLabel, 0, 0)
        # 第一行第二列 占用1行两列
        mainLayout.addWidget(nameLineEdit, 0, 1, 1, 2)
        mainLayout.addWidget(passwordLabel, 1, 0)
        mainLayout.addWidget(passwordLineEdit, 1, 1, 1, 2)
        mainLayout.addWidget(btnOK, 2, 1)
        mainLayout.addWidget(btnCancel, 2, 2)


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

第二节 QLineEdit控件与回显模式

1. QLineEdit控件回显模式

1. 基本功能：输入单行的文本
2. EchoMode（回显模式） 4种回显模式
   1. Normal
   2. NoEcho（输入但是不显示）
   3. Password（隐藏密码）
   4. PasswordEchoOnEdit (先显示过一会，变成password模式)
3. 占位信息：placeholdertext

from PyQt5.QtWidgets import *
import sys


class QLineEditEchoMode(QWidget):
    def __init__(self):
        super(QLineEditEchoMode, self).__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle('文本输入框的回显模式')

        formLayout = QFormLayout()

        normalLineEdit = QLineEdit()
        noEchoLineEdit = QLineEdit()
        passwordLineEdit = QLineEdit()
        passwordEchoOnEditLineEdit = QLineEdit()

        formLayout.addRow("Normal", normalLineEdit)
        formLayout.addRow("NoEcho", noEchoLineEdit)
        formLayout.addRow("Password", passwordLineEdit)
        formLayout.addRow("PasswordEchoOnEdit", passwordEchoOnEditLineEdit)

        # placeholdertext

        normalLineEdit.setPlaceholderText("Normal")
        noEchoLineEdit.setPlaceholderText("NoEcho")
        passwordLineEdit.setPlaceholderText("Password")
        passwordEchoOnEditLineEdit.setPlaceholderText("PasswordEchoOnEdit")

        normalLineEdit.setEchoMode(QLineEdit.Normal)
        noEchoLineEdit.setEchoMode(QLineEdit.NoEcho)
        passwordLineEdit.setEchoMode(QLineEdit.Password)
        passwordEchoOnEditLineEdit.setEchoMode(QLineEdit.PasswordEchoOnEdit)

        self.setLayout(formLayout)


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

2. QLineEdit控件校验器

1. 现在QLineEdit控件的输入（校验器）：如限制只能输入整数、浮点数或满足一定条件的字符串
2. from PyQt5.QtGui import QIntValidator, QDoubleValidator, QRegExpValidator
3. 正则表达式类：from PyQt5.QtCore import QRegExp

from PyQt5.QtWidgets import *
from PyQt5.QtGui import QIntValidator, QDoubleValidator, QRegExpValidator
from PyQt5.QtCore import QRegExp
import sys


class QLineEditValidator(QWidget):
    def __init__(self):
        super(QLineEditValidator, self).__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle('校验器')

        # 创建表单布局
        formLayout = QFormLayout()

        intLineEdit = QLineEdit()
        doubleLineEdit = QLineEdit()
        validatorLineEdit = QLineEdit()

        formLayout.addRow('整数类型', intLineEdit)
        formLayout.addRow('浮点类型', doubleLineEdit)
        formLayout.addRow('数字和字母', validatorLineEdit)

        intLineEdit.setPlaceholderText('整型')
        doubleLineEdit.setPlaceholderText('浮点型')
        validatorLineEdit.setPlaceholderText('字母和数字')

        # 整数校验器 [1,99]
        intValidator = QIntValidator(self)
        intValidator.setRange(1, 99)

        # 浮点校验器 [-360,360]，精度：小数点后2位
        doubleValidator = QDoubleValidator(self)
        doubleValidator.setRange(-360, 360)
        # 标准的记号表示法，让浮点数正常显示
        doubleValidator.setNotation(QDoubleValidator.StandardNotation)
        # 设置精度，小数点2位
        doubleValidator.setDecimals(2)

        # 字符和数字
        reg = QRegExp('[a-zA-z0-9]+$')
        validator = QRegExpValidator(self)
        validator.setRegExp(reg)

        # 设置校验器
        intLineEdit.setValidator(intValidator)
        doubleLineEdit.setValidator(doubleValidator)
        validatorLineEdit.setValidator(validator)

        self.setLayout(formLayout)


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

3. QLineEdit控件通过掩码限制输入

1. 用掩码限制QLineEdit控件的输入
2. QLineEdit控件的setInputMask方法

A    ASCII字母字符是必须输入的(A-Z、a-z)
a    ASCII字母字符是允许输入的,但不是必需的(A-Z、a-z)
N    ASCII字母字符是必须输入的(A-Z、a-z、0-9)
n    ASII字母字符是允许输入的,但不是必需的(A-Z、a-z、0-9)
X    任何字符都是必须输入的
x    任何字符都是允许输入的,但不是必需的
9    ASCII数字字符是必须输入的(0-9)
0    ASCII数字字符是允许输入的,但不是必需的(0-9)
D    ASCII数字字符是必须输入的(1-9)
d    ASCII数字字符是允许输入的,但不是必需的(1-9)
#    ASCI数字字符或加减符号是允许输入的,但不是必需的
H    十六进制格式字符是必须输入的(A-F、a-f、0-9)
h    十六进制格式字符是允许输入的,但不是必需的(A-F、a-f、0-9)
B    二进制格式字符是必须输入的(0,1)
b    二进制格式字符是允许输入的,但不是必需的(0,1)
>    所有的字母字符都大写
<    所有的字母字符都小写
!    关闭大小写转换
\    使用"\"转义上面列出的字符

from PyQt5.QtWidgets import *
import sys


class QLineEditMask(QWidget) :
    def __init__(self):
        super(QLineEditMask,self).__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle('用掩码限制QLineEdit控件的输入')
        formLayout = QFormLayout()

        ipLineEdit = QLineEdit()
        macLineEdit = QLineEdit()
        dateLineEdit = QLineEdit()
        licenseLineEdit = QLineEdit()
        # 192.168.21.45
        # ;后代表没有输入时候占位符号
        ipLineEdit.setInputMask('000.000.000.000;_')
        macLineEdit.setInputMask('HH:HH:HH:HH:HH:HH;_')
        dateLineEdit.setInputMask('0000-00-00')
        licenseLineEdit.setInputMask('>AAAAA-AAAAA-AAAAA-AAAAA-AAAAA;#')

        formLayout.addRow('数字掩码',ipLineEdit)
        formLayout.addRow('Mac掩码', macLineEdit)
        formLayout.addRow('日期掩码',dateLineEdit)
        formLayout.addRow('许可证掩码',licenseLineEdit)

        self.setLayout(formLayout)


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

4. QLineEdit控件综合案例

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


class QLineEditDemo(QWidget):
    def __init__(self):
        super(QLineEditDemo, self).__init__()
        self.initUI()

    def initUI(self):
        edit1 = QLineEdit()
        # 使用int校验器
        edit1.setValidator(QIntValidator())
        edit1.setMaxLength(4)  # 不超过9999
        edit1.setAlignment(Qt.AlignRight)
        edit1.setFont(QFont('Arial', 20))

        edit2 = QLineEdit()
        edit2.setValidator(QDoubleValidator(0.99, 99.99, 2))

        edit3 = QLineEdit()
        edit3.setInputMask('99_9999_999999;#')

        edit4 = QLineEdit()
        edit4.textChanged.connect(self.textChanged)

        edit5 = QLineEdit()
        edit5.setEchoMode(QLineEdit.Password)
        edit5.editingFinished.connect(self.enterPress)

        edit6 = QLineEdit('Hello PyQt5')
        edit6.setReadOnly(True)

        formLayout = QFormLayout()
        formLayout.addRow('整数校验', edit1)
        formLayout.addRow('浮点数校验', edit2)
        formLayout.addRow('Input Mask', edit3)
        formLayout.addRow('文本变化', edit4)
        formLayout.addRow('密码', edit5)
        formLayout.addRow('只读', edit6)
        self.setLayout(formLayout)
        self.setWindowTitle('QLineEdit综合案例')

    def textChanged(self, text):
        print('输入的内容：' + text)

    def enterPress(self):
        print('已输入值')


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

第三节 TextEdit控件

1. TextEdit控件使用

1. 输入多行文本。
2. 它也支持HTML标签。可以改变文本颜色和尺寸。

from PyQt5.QtWidgets import *
import sys


class QTextEditDemo(QWidget):
    def __init__(self):
        super(QTextEditDemo, self).__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle('QTextEdit控件演示')

        self.resize(300, 320)

        self.textEdit = QTextEdit()
        self.buttonText = QPushButton('显示文本')
        self.buttonHTML = QPushButton('显示HTML')

        self.buttonToText = QPushButton('获取文本')
        self.buttonToHTML = QPushButton('获取HTML')

        layout = QVBoxLayout()
        layout.addWidget(self.textEdit)
        layout.addWidget(self.buttonText)
        layout.addWidget(self.buttonToText)
        layout.addWidget(self.buttonHTML)
        layout.addWidget(self.buttonToHTML)

        self.setLayout(layout)

        self.buttonText.clicked.connect(self.onClick_ButtonText)
        self.buttonHTML.clicked.connect(self.onClick_ButtonHTML)

        self.buttonToText.clicked.connect(self.onClick_ButtonToText)
        self.buttonToHTML.clicked.connect(self.onClick_ButtonToHTML)

    def onClick_ButtonText(self):
        self.textEdit.setPlainText('Hello World，世界你好吗？')

    def onClick_ButtonToText(self):
        print(self.textEdit.toPlainText())

    def onClick_ButtonHTML(self):
        self.textEdit.setHtml('<font color="blue" size="5">Hello World</font>')

    def onClick_ButtonToHTML(self):
        print(self.textEdit.toHtml())


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