Article Outline
Python pyqt (gui) example 'i18n'
Modules used in program:
import i18n_rc
i18n
Python pyqt example: i18n
#!/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.
##
## $QT_BEGIN_LICENSE:BSD$
## You may use this file under the terms of the BSD license as follows:
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## modification, are permitted provided that the following conditions are
## met:
## * 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
## notice, this list of conditions and the following disclaimer in
## 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
## permission.
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## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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## $QT_END_LICENSE$
##
#############################################################################
from PyQt5.QtCore import QDir, QEvent, Qt, QT_TRANSLATE_NOOP, QTranslator
from PyQt5.QtGui import QColor, QPalette
from PyQt5.QtWidgets import (QAction, QApplication, QCheckBox, QDialog,
QDialogButtonBox, QGridLayout, QGroupBox, QListWidget, QMainWindow,
QRadioButton, QVBoxLayout, QWidget)
import i18n_rc
class LanguageChooser(QDialog):
def __init__(self, parent=None):
super(LanguageChooser, self).__init__(parent, Qt.WindowStaysOnTopHint)
self.qmFileForCheckBoxMap = {}
self.mainWindowForCheckBoxMap = {}
groupBox = QGroupBox("Languages")
groupBoxLayout = QGridLayout()
qmFiles = self.findQmFiles()
for i, qmf in enumerate(qmFiles):
checkBox = QCheckBox(self.languageName(qmf))
self.qmFileForCheckBoxMap[checkBox] = qmf
checkBox.toggled.connect(self.checkBoxToggled)
groupBoxLayout.addWidget(checkBox, i / 2, i % 2)
groupBox.setLayout(groupBoxLayout)
buttonBox = QDialogButtonBox()
showAllButton = buttonBox.addButton("Show All",
QDialogButtonBox.ActionRole)
hideAllButton = buttonBox.addButton("Hide All",
QDialogButtonBox.ActionRole)
showAllButton.clicked.connect(self.showAll)
hideAllButton.clicked.connect(self.hideAll)
mainLayout = QVBoxLayout()
mainLayout.addWidget(groupBox)
mainLayout.addWidget(buttonBox)
self.setLayout(mainLayout)
self.setWindowTitle("I18N")
def eventFilter(self, object, event):
if event.type() == QEvent.Close:
if isinstance(object, MainWindow):
window = object
for checkBox, w in self.mainWindowForCheckBoxMap.items():
if w is window:
break
else:
checkBox = None
if checkBox:
checkBox.setChecked(False)
return QWidget.eventFilter(self, object, event)
def closeEvent(self, event):
QApplication.instance().quit()
def checkBoxToggled(self):
checkBox = self.sender()
window = self.mainWindowForCheckBoxMap.get(checkBox)
if not window:
translator = QTranslator()
translator.load(self.qmFileForCheckBoxMap[checkBox])
QApplication.installTranslator(translator)
# Because we will be installing an event filter for the main window
# it is important that this instance isn't garbage collected before
# the main window when the program terminates. We ensure this by
# making the main window a child of this one.
window = MainWindow(self)
window.setPalette(QPalette(self.colorForLanguage(checkBox.text())))
window.installEventFilter(self)
self.mainWindowForCheckBoxMap[checkBox] = window
window.setVisible(checkBox.isChecked())
def showAll(self):
for checkBox in self.qmFileForCheckBoxMap.keys():
checkBox.setChecked(True)
def hideAll(self):
for checkBox in self.qmFileForCheckBoxMap.keys():
checkBox.setChecked(False)
def findQmFiles(self):
trans_dir = QDir(':/translations')
fileNames = trans_dir.entryList(['*.qm'], QDir.Files, QDir.Name)
return [trans_dir.filePath(fn) for fn in fileNames]
def languageName(self, qmFile):
translator = QTranslator()
translator.load(qmFile)
return translator.translate("MainWindow", "English")
def colorForLanguage(self, language):
hashValue = hash(language)
red = 156 + (hashValue & 0x3F)
green = 156 + ((hashValue >> 6) & 0x3F)
blue = 156 + ((hashValue >> 12) & 0x3F)
return QColor(red, green, blue)
class MainWindow(QMainWindow):
listEntries = [QT_TRANSLATE_NOOP("MainWindow", "First"),
QT_TRANSLATE_NOOP("MainWindow", "Second"),
QT_TRANSLATE_NOOP("MainWindow", "Third")]
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.centralWidget = QWidget()
self.setCentralWidget(self.centralWidget)
self.createGroupBox()
listWidget = QListWidget()
for le in MainWindow.listEntries:
listWidget.addItem(self.tr(le))
mainLayout = QVBoxLayout()
mainLayout.addWidget(self.groupBox)
mainLayout.addWidget(listWidget)
self.centralWidget.setLayout(mainLayout)
exitAction = QAction(self.tr("E&xit"), self,
triggered=QApplication.instance().quit)
fileMenu = self.menuBar().addMenu(self.tr("&File"))
fileMenu.setPalette(QPalette(Qt.red))
fileMenu.addAction(exitAction)
self.setWindowTitle(self.tr("Language: %s") % self.tr("English"))
self.statusBar().showMessage(self.tr("Internationalization Example"))
if self.tr("LTR") == "RTL":
self.setLayoutDirection(Qt.RightToLeft)
def createGroupBox(self):
self.groupBox = QGroupBox(self.tr("View"))
perspectiveRadioButton = QRadioButton(self.tr("Perspective"))
isometricRadioButton = QRadioButton(self.tr("Isometric"))
obliqueRadioButton = QRadioButton(self.tr("Oblique"))
perspectiveRadioButton.setChecked(True)
self.groupBoxLayout = QVBoxLayout()
self.groupBoxLayout.addWidget(perspectiveRadioButton)
self.groupBoxLayout.addWidget(isometricRadioButton)
self.groupBoxLayout.addWidget(obliqueRadioButton)
self.groupBox.setLayout(self.groupBoxLayout)
if __name__ == "__main__":
import sys
app = QApplication(sys.argv)
chooser = LanguageChooser()
chooser.show()
sys.exit(app.exec_())
Useful links
- Learn PyQt: https://pythonbasics.org/pyqt-hello-world/
- Install PyQt: https://pythonbasics.org/install-pyqt/