Pyqt5 rapid development and practice 4.9 dialog controls

PyQt5 Rapid development and actual combat

4. The first 4 Chapter PyQt5 Basic window control

4.9 Dialog class control

4.9.1 QDialog

stay PyQt 5 A series of standard dialog box classes are defined in , Users can easily and quickly complete the font size through various classes 、 Font color and file selection .

QDialog The subclasses of class mainly include QMessageBox.QFileDialog,QFontDialog ,QInputDialog etc. .

QDialog Common methods in class

Method	describe
setWindowTitle()	Set dialog title
setWindowModality()	Set window mode . The values are as follows : - Qt.NonModal, Modeless , It can interact with other windows of the program ;Qt.WindowModal, Window mode , The program does not finish processing the current dialog , Interaction with the parent window of the dialog box will be blocked ;Qt.ApplicationModal, Application mode , Block interaction with any other window

QDialog Use

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

class DialogDemo(QMainWindow):
    def __init__(self,parent = None):
        super(DialogDemo, self).__init__(parent)
        self.setWindowTitle("Dialog Case study ")
        self.resize(350 , 300)

        self.btn = QPushButton(self)
        self.btn.setText(" Pop-up dialog box ")
        self.btn.move(50 , 50)
        self.btn.clicked.connect(self.showdialog)

    def showdialog(self):
        dialog = QDialog()
        btn = QPushButton("ok",dialog)
        btn.move(50 , 50)
        dialog.setWindowTitle("Dialog")
        dialog.setWindowModality(Qt.ApplicationModal)
        dialog.exec_()

if __name__ == '__main__':
    from pyqt5_plugins.examples.exampleqmlitem import QtCore
    QtCore.QCoreApplication.setAttribute(QtCore.Qt.AA_EnableHighDpiScaling)
    app = QApplication(sys.argv)
    win = DialogDemo()
    win.show()
    sys.exit(app.exec_())

4.9.2 QMessageBox

QMessageBox It's a general pop-up dialog box , Used to display messages , Allows users to feed back messages by clicking on different standard buttons . Each standard button has a predefined text 、 Roles and hexadecimal numbers .

QMessageBox Class provides many common pop-up dialog boxes , As a reminder 、 Warning 、 error 、 inquiry 、 About waiting dialog . These different types of QMessageBox The dialog box just displays different icons , Other functions are the same .

QMessageBox Common methods in class

Method	describe
information(QWidget,parent,title,text,buttons,defaultButton)	Pop up message dialog box , The parameters are explained as follows : parent, Specified parent window control ;title, Dialog title text, Dialog text ;buttons: Multiple standard buttons , The default is OK Button ;defaultButton: The standard button selected by default , The default is the first standard button
question(Qwidget parent,title, text, buttons, defaultButton)	A question and answer dialog box will pop up （ The parameters are explained as above ）
waming(QWidget parent,title, text, buttons, defaultButton)	A warning dialog box will pop up （ The parameters are explained as above ）
ctitical(QWidget parent,title, text, buttons , defaultButton)	A serious error dialog box will pop up （ The parameters are explained as above ）
about(QWidget parent,titIe, text)	Pop up the dialog about （ The parameters are explained as above ）
setTitle()	Set title
setText()	Set the message body
setIcon()	Set the picture of the pop-up dialog

QMessageBox The standard button type

type	describe
QMessage.Ok	Agree to operate
QMessage.Cancel	Cancel operation
QMessage.Yes	Agree to operate
QMessage.No	Cancel operation
QMessage.About	Termination operation
QMessage.Retry	Retrying the operation
QMessage.Ignore	Ignore action

5 Common message dialog box and its display effect

QMessageBox Use cases

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

class MyWindow(QWidget):
    def __init__(self):
        super(MyWindow, self).__init__()
        self.setWindowTitle("QMessageBox Case study ")
        self.resize(300 ,100)
        self.myButton = QPushButton(self)
        self.myButton.setText(" Click to pop up the message box ")
        self.myButton.clicked.connect(self.msg)

    def msg(self):
        # information
        reply = QMessageBox.information(self," title "," Message body ",QMessageBox.Yes | QMessageBox.No,QMessageBox.Yes)
        print(reply)

if __name__ == '__main__':
    from pyqt5_plugins.examples.exampleqmlitem import QtCore
    QtCore.QCoreApplication.setAttribute(QtCore.Qt.AA_EnableHighDpiScaling)
    app = QApplication(sys.argv)
    win = MyWindow()
    win.show()
    sys.exit(app.exec_())

4.9.3 QInputDialog

QInputDialog Control is a standard dialog box , It consists of a text box and two buttons （OK Button and Cancel Button ） form . When the user clicks OK Button or press Enter Post key , The parent window can be collected through QInputDialog Control .QInputDialog Control is QDialog Part of the standard dialog .
stay QInputDialog Control can enter numbers 、 Options in string or list . The tag is used to prompt the necessary information .

QInputDialog Common methods in class

Method	describe
getInt()	Get standard integer input from control
getDouble()	Get standard floating-point input from control
getText()	Get the standard string input from the control
getItem()	Get the option input in the list from the control

QInputDialog Use case of

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

class InputdialogDemo(QWidget):
    def __init__(self,parent = None):
        super(InputdialogDemo, self).__init__(parent)
        layout = QFormLayout()
        self.btn1 = QPushButton(" Get the options in the list ")
        self.btn1.clicked.connect(self.getItem)
        self.le1 = QLineEdit()
        layout.addRow(self.btn1,self.le1)

        self.btn2 = QPushButton(" Get string ")
        self.btn2.clicked.connect(self.getText)
        self.le2 = QLineEdit()
        layout.addRow(self.btn2,self.le2)

        self.btn3 = QPushButton(" Get an integer ")
        self.btn3.clicked.connect(self.getInt)
        self.le3 = QLineEdit()
        layout.addRow(self.btn3,self.le3)
        self.setLayout(layout)
        self.setWindowTitle("Input Dialog  Case study ")

    def getItem(self):
        items = ("C","C++","Java","Python")
        item , ok = QInputDialog.getItem(self,"select input dialog"," Language list ",items,0,False)
        if ok and item:
            self.le1.setText(item)

    def getText(self):
        text , ok = QInputDialog.getText(self,"Text Input Dialog",' Enter a name :')
        if ok :
             self.le2.setText(str(text))

    def getInt(self):
        num , ok = QInputDialog.getInt(self,"Integer input dialog"," Input number ")
        if ok :
            self.le3.setText(str(num))

if __name__ == '__main__':
    from pyqt5_plugins.examples.exampleqmlitem import QtCore
    QtCore.QCoreApplication.setAttribute(QtCore.Qt.AA_EnableHighDpiScaling)
    app = QApplication(sys.argv)
    win = InputdialogDemo()
    win.show()
    sys.exit(app.exec_())

4.9.4 QFontDialog

QFontDialog Control is a common font selection dialog box , Allows the user to select the font size of the displayed text 、 Style and format .QFontDialog yes QDialog Part of the standard dialog . Use QFontDialog Class static methods getFont(), You can select the display font size of the text from the font selection dialog box 、 Style and format .

QFontDialog Use

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

class FontDialogDemo(QWidget):
    def __init__(self,parent = None):
        super(FontDialogDemo, self).__init__(parent)
        layout = QVBoxLayout()
        self.fontButton = QPushButton("Choose font")
        self.fontButton.clicked.connect(self.getFont)
        layout.addWidget(self.fontButton)
        self.fontLineEdit = QLabel("Hello ,  Test font case ")
        layout.addWidget(self.fontLineEdit)
        self.setLayout(layout)
        self.setWindowTitle("Font Dialog Case study ")

    def getFont(self):
        font , ok = QFontDialog.getFont()
        if ok :
            self.fontLineEdit.setFont(font)


if __name__ == '__main__':
    from pyqt5_plugins.examples.exampleqmlitem import QtCore
    QtCore.QCoreApplication.setAttribute(QtCore.Qt.AA_EnableHighDpiScaling)
    app = QApplication(sys.argv)
    win = FontDialogDemo()
    win.show()
    sys.exit(app.exec_())

4.9.5 QFileDialog

QFileDialog Is a standard dialog for opening and saving files .QFileDialog Class inherits from QDialog class .
QFileDialog The file filter is used when opening the file , Used to display the file with the specified extension . Can also be set to use OFileDialog The starting directory when opening the file and the file with the specified extension .

QFileDialog Common methods in class

Method	describe
getOpenFileName()	Returns the name of the file selected by the user , And open the file
getSaveFileName()	Use the file name selected by the user and save the file
setFileMode()	File types that can be selected , Enumeration constants are : QFileDialog.AnyFile, Any document QFileDialog.ExistingFile, Existing files . QFileDialog.Directory, File directory QFileDialog.ExistingFiles, Multiple files already exist
setFilter()	catalog filter , Only the file types allowed by the filter are displayed

QFileDialog Use

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


class filedialogdemo(QWidget):
   def __init__(self, parent=None):
      super(filedialogdemo, self).__init__(parent)
      layout = QVBoxLayout()
      self.btn = QPushButton(" Loading pictures ")
      self.btn.clicked.connect(self.getfile)
      layout.addWidget(self.btn)
      self.le = QLabel("")
      layout.addWidget(self.le)
      self.btn1 = QPushButton(" Load text file ")
      self.btn1.clicked.connect(self.getfiles)
      layout.addWidget(self.btn1)
      self.contents = QTextEdit()
      layout.addWidget(self.contents)
      self.setLayout(layout)
      self.setWindowTitle("File Dialog  Example ")

   def getfile(self):
      fname, _ = QFileDialog.getOpenFileName(self, 'Open file', 'd:\\', "Image files (*.jpg *.gif)")
      self.le.setPixmap(QPixmap(fname))

   def getfiles(self):
      dlg = QFileDialog()
      dlg.setFileMode(QFileDialog.AnyFile)
      dlg.setFilter(QDir.Files)

      if dlg.exec_():
         filenames = dlg.selectedFiles()
         f = open(filenames[0], 'r',encoding='UTF-8')

         with f:
            data = f.read()
            self.contents.setText(data)

if __name__ == '__main__':
    # from pyqt5_plugins.examples.exampleqmlitem import QtCore
    # QtCore.QCoreApplication.setAttribute(QtCore.Qt.AA_EnableHighDpiScaling)
    app = QApplication(sys.argv)
    win = filedialogdemo()
    win.show()
    sys.exit(app.exec_())