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Python pyqt (gui) example 'regexp'
regexp
Python pyqt example: regexp
#!/usr/bin/env python
#############################################################################
##
## Copyright (C) 2013 Riverbank Computing Limited.
## Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
## All rights reserved.
##
## This file is part of the examples of PyQt.
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## $QT_BEGIN_LICENSE:BSD$
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## * Redistributions of source code must retain the above copyright
## notice, this list of conditions and the following disclaimer.
## * Redistributions in binary form must reproduce the above copyright
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## the documentation and/or other materials provided with the
## distribution.
## * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
## the names of its contributors may be used to endorse or promote
## products derived from this software without specific prior written
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## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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## $QT_END_LICENSE$
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#############################################################################
from PyQt5.QtCore import QRegExp, Qt
from PyQt5.QtGui import QPalette
from PyQt5.QtWidgets import (QApplication, QCheckBox, QComboBox, QDialog,
QGridLayout, QHBoxLayout, QLabel, QLineEdit, QSizePolicy)
class RegExpDialog(QDialog):
MaxCaptures = 6
def __init__(self, parent=None):
super(RegExpDialog, self).__init__(parent)
self.patternComboBox = QComboBox()
self.patternComboBox.setEditable(True)
self.patternComboBox.setSizePolicy(QSizePolicy.Expanding,
QSizePolicy.Preferred)
patternLabel = QLabel("&Pattern:")
patternLabel.setBuddy(self.patternComboBox)
self.escapedPatternLineEdit = QLineEdit()
self.escapedPatternLineEdit.setReadOnly(True)
palette = self.escapedPatternLineEdit.palette()
palette.setBrush(QPalette.Base,
palette.brush(QPalette.Disabled, QPalette.Base))
self.escapedPatternLineEdit.setPalette(palette)
escapedPatternLabel = QLabel("&Escaped Pattern:")
escapedPatternLabel.setBuddy(self.escapedPatternLineEdit)
self.syntaxComboBox = QComboBox()
self.syntaxComboBox.addItem("Regular expression v1", QRegExp.RegExp)
self.syntaxComboBox.addItem("Regular expression v2", QRegExp.RegExp2)
self.syntaxComboBox.addItem("Wildcard", QRegExp.Wildcard)
self.syntaxComboBox.addItem("Fixed string", QRegExp.FixedString)
syntaxLabel = QLabel("&Pattern Syntax:")
syntaxLabel.setBuddy(self.syntaxComboBox)
self.textComboBox = QComboBox()
self.textComboBox.setEditable(True)
self.textComboBox.setSizePolicy(QSizePolicy.Expanding,
QSizePolicy.Preferred)
textLabel = QLabel("&Text:")
textLabel.setBuddy(self.textComboBox)
self.caseSensitiveCheckBox = QCheckBox("Case &Sensitive")
self.caseSensitiveCheckBox.setChecked(True)
self.minimalCheckBox = QCheckBox("&Minimal")
indexLabel = QLabel("Index of Match:")
self.indexEdit = QLineEdit()
self.indexEdit.setReadOnly(True)
matchedLengthLabel = QLabel("Matched Length:")
self.matchedLengthEdit = QLineEdit()
self.matchedLengthEdit.setReadOnly(True)
self.captureLabels = []
self.captureEdits = []
for i in range(self.MaxCaptures):
self.captureLabels.append(QLabel("Capture %d:" % i))
self.captureEdits.append(QLineEdit())
self.captureEdits[i].setReadOnly(True)
self.captureLabels[0].setText("Match:")
checkBoxLayout = QHBoxLayout()
checkBoxLayout.addWidget(self.caseSensitiveCheckBox)
checkBoxLayout.addWidget(self.minimalCheckBox)
checkBoxLayout.addStretch(1)
mainLayout = QGridLayout()
mainLayout.addWidget(patternLabel, 0, 0)
mainLayout.addWidget(self.patternComboBox, 0, 1)
mainLayout.addWidget(escapedPatternLabel, 1, 0)
mainLayout.addWidget(self.escapedPatternLineEdit, 1, 1)
mainLayout.addWidget(syntaxLabel, 2, 0)
mainLayout.addWidget(self.syntaxComboBox, 2, 1)
mainLayout.addLayout(checkBoxLayout, 3, 0, 1, 2)
mainLayout.addWidget(textLabel, 4, 0)
mainLayout.addWidget(self.textComboBox, 4, 1)
mainLayout.addWidget(indexLabel, 5, 0)
mainLayout.addWidget(self.indexEdit, 5, 1)
mainLayout.addWidget(matchedLengthLabel, 6, 0)
mainLayout.addWidget(self.matchedLengthEdit, 6, 1)
for i in range(self.MaxCaptures):
mainLayout.addWidget(self.captureLabels[i], 7 + i, 0)
mainLayout.addWidget(self.captureEdits[i], 7 + i, 1)
self.setLayout(mainLayout)
self.patternComboBox.editTextChanged.connect(self.refresh)
self.textComboBox.editTextChanged.connect(self.refresh)
self.caseSensitiveCheckBox.toggled.connect(self.refresh)
self.minimalCheckBox.toggled.connect(self.refresh)
self.syntaxComboBox.currentIndexChanged.connect(self.refresh)
self.patternComboBox.addItem("[A-Za-z_]+([A-Za-z_0-9]*)")
self.textComboBox.addItem("(10 + delta4)* 32")
self.setWindowTitle("RegExp")
self.setFixedHeight(self.sizeHint().height())
self.refresh()
def refresh(self):
self.setUpdatesEnabled(False)
pattern = self.patternComboBox.currentText()
text = self.textComboBox.currentText()
escaped = str(pattern)
escaped.replace('\\', '\\\\')
escaped.replace('"', '\\"')
self.escapedPatternLineEdit.setText('"' + escaped + '"')
rx = QRegExp(pattern)
cs = Qt.CaseSensitive if self.caseSensitiveCheckBox.isChecked() else Qt.CaseInsensitive
rx.setCaseSensitivity(cs)
rx.setMinimal(self.minimalCheckBox.isChecked())
syntax = self.syntaxComboBox.itemData(self.syntaxComboBox.currentIndex())
rx.setPatternSyntax(syntax)
palette = self.patternComboBox.palette()
if rx.isValid():
palette.setColor(QPalette.Text,
self.textComboBox.palette().color(QPalette.Text))
else:
palette.setColor(QPalette.Text, Qt.red)
self.patternComboBox.setPalette(palette)
self.indexEdit.setText(str(rx.indexIn(text)))
self.matchedLengthEdit.setText(str(rx.matchedLength()))
for i in range(self.MaxCaptures):
self.captureLabels[i].setEnabled(i <= rx.captureCount())
self.captureEdits[i].setEnabled(i <= rx.captureCount())
self.captureEdits[i].setText(rx.cap(i))
self.setUpdatesEnabled(True)
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
dialog = RegExpDialog()
dialog.show()
sys.exit(app.exec_())
Useful links
- Learn PyQt: https://pythonbasics.org/pyqt-hello-world/
- Install PyQt: https://pythonbasics.org/install-pyqt/