Always Use RTL in QPlainTextEdit for PyQt4

[leomoon]

Hello,

I'm very new to PyQt and I have 3 simple problem. But I can't make it work.

1- I want the QPlainTextEdit to stay RTL (with text-align right) at ALL TIMES unless I tell it to go LTR. Doesn't matter what kind of text is being entered.
2- How to change QPlainTextEdit font using QFontComboBox.
3- How to change QPlainTextEdit font point size using QSpinBox.

Thanks for your help.

[anda_skoa]

1- I want the QPlainTextEdit to stay RTL (with text-align right) at ALL TIMES unless I tell it to go LTR. Doesn't matter what kind of text is being entered.

Probably by setting the layout direction on the defaultTextOption property of the edit's text document

2- How to change QPlainTextEdit font using QFontComboBox.

By changing the default font of the edit's text document.

3- How to change QPlainTextEdit font point size using QSpinBox.

By changing the default font of the edit's text document.

Cheers,
_

[leomoon]

Yea, I've tried that. That just puts the scrollerbar to the left! And I tried to align text to right, no luck there either!
self.editor.setAlignment(QtCore.Qt.AlignRight)
self.editor.setAlignment(Qt.AlignLeft)

Both say QPlainTextEdit doesn't have setAlignment attribute!

[anda_skoa]

Yea, I've tried that.
That just puts the scrollerbar to the left!

Can you show that code?
It sounds a bit like you set the layout direction on the editor itself.

Cheers,
_

[leomoon]

This is a simple example:

# -*- coding: utf-8 -*-
 
# Form implementation generated from reading ui file 'test.ui'
#
# Created by: PyQt4 UI code generator 4.11.4
#
# WARNING! All changes made in this file will be lost!
 
from PyQt4 import QtCore, QtGui
 
try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s
 
try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)
 
class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName(_fromUtf8("MainWindow"))
        MainWindow.resize(640, 480)
        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
        self.horizontalLayout = QtGui.QHBoxLayout(self.centralwidget)
        self.horizontalLayout.setObjectName(_fromUtf8("horizontalLayout"))
        self.plainTextEdit = QtGui.QPlainTextEdit(self.centralwidget)
        self.plainTextEdit.setLayoutDirection(QtCore.Qt.RightToLeft)
        self.plainTextEdit.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
        self.plainTextEdit.setObjectName(_fromUtf8("plainTextEdit"))
        self.horizontalLayout.addWidget(self.plainTextEdit)
        MainWindow.setCentralWidget(self.centralwidget)
 
        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)
 
    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow", None))
 
 
if __name__ == "__main__":
    import sys
    app = QtGui.QApplication(sys.argv)
    MainWindow = QtGui.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())

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

# Form implementation generated from reading ui file 'test.ui'
#
# Created by: PyQt4 UI code generator 4.11.4
#
# WARNING! All changes made in this file will be lost!

from PyQt4 import QtCore, QtGui

try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s

try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName(_fromUtf8("MainWindow"))
        MainWindow.resize(640, 480)
        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
        self.horizontalLayout = QtGui.QHBoxLayout(self.centralwidget)
        self.horizontalLayout.setObjectName(_fromUtf8("horizontalLayout"))
        self.plainTextEdit = QtGui.QPlainTextEdit(self.centralwidget)
        self.plainTextEdit.setLayoutDirection(QtCore.Qt.RightToLeft)
        self.plainTextEdit.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
        self.plainTextEdit.setObjectName(_fromUtf8("plainTextEdit"))
        self.horizontalLayout.addWidget(self.plainTextEdit)
        MainWindow.setCentralWidget(self.centralwidget)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow", None))


if __name__ == "__main__":
    import sys
    app = QtGui.QApplication(sys.argv)
    MainWindow = QtGui.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())

To copy to clipboard, switch view to plain text mode 

Probably I'm missing something really simple!

[anda_skoa]

Probably I'm missing something really simple!

Yes, you are missing that I wrote "the edit's text document" :-)

The text widgets operate on a QTextDocument instance, which handles all the text processing.
It has properties for default font and default text options, one of which is the text's layout direction.

Cheers,
_

[leomoon]

Dude,

I'm lost. I don't know how to use a QTextDocument to edit the editor's property. I keep getting error. And I can't find any example anywhere about forcing RTL.

[anda_skoa]

I have no idea what you are talking about, it certainly has nothing to do with what I suggested earlier.

Get the text document from the text edit, change the document's properties.

Cheers,
_

[leomoon]

I made an example if anybody else had the same problem. This example changes the font size, font name and toggles direction on the QTextEdit. font name and font size will be changed on the whole editor and toggling direction is not same as align left and right.

# -*- coding: utf-8 -*-
 
# Form implementation generated from reading ui file 'toggleDir.ui'
#
# Created by: PyQt4 UI code generator 4.11.4
#
# WARNING! All changes made in this file will be lost!
 
from PyQt4 import QtCore, QtGui
 
dir = 'rtl'
 
try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s
 
try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)
 
class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName(_fromUtf8("MainWindow"))
        MainWindow.resize(350, 350)
        MainWindow.setMinimumSize(QtCore.QSize(350, 350))
        MainWindow.setMaximumSize(QtCore.QSize(350, 350))
        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
        self.verticalLayout = QtGui.QVBoxLayout(self.centralwidget)
        self.verticalLayout.setObjectName(_fromUtf8("verticalLayout"))
        self.horizontalLayout = QtGui.QHBoxLayout()
        self.horizontalLayout.setObjectName(_fromUtf8("horizontalLayout"))
        self.fontName = QtGui.QFontComboBox(self.centralwidget)
        self.fontName.setObjectName(_fromUtf8("fontName"))
        self.horizontalLayout.addWidget(self.fontName)
        self.fontSize = QtGui.QSpinBox(self.centralwidget)
        self.fontSize.setProperty("value", 11)
        self.fontSize.setObjectName(_fromUtf8("fontSize"))
        self.horizontalLayout.addWidget(self.fontSize)
        self.verticalLayout.addLayout(self.horizontalLayout)
        self.edit = QtGui.QTextEdit(self.centralwidget)
        self.edit.setObjectName(_fromUtf8("edit"))
        self.edit.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
        self.verticalLayout.addWidget(self.edit)
        self.toggleDirBtn = QtGui.QPushButton(self.centralwidget)
        font = QtGui.QFont()
        font.setPointSize(15)
        self.toggleDirBtn.setFont(font)
        self.toggleDirBtn.setObjectName(_fromUtf8("toggleDirBtn"))
        self.verticalLayout.addWidget(self.toggleDirBtn)
        MainWindow.setCentralWidget(self.centralwidget)
        option=self.edit.document().defaultTextOption()
        option.setTextDirection(QtCore.Qt.RightToLeft)
        self.edit.document().setDefaultTextOption(option)
        self.edit.setLayoutDirection(QtCore.Qt.RightToLeft) #switch scrollerbar
        self.edit.setTabStopWidth(33) #set tab size for editor
        self.fontName.currentFontChanged.connect(self._fontName)
        self.fontSize.valueChanged.connect(self._fontSize)
        self.toggleDirBtn.clicked.connect(self._toggleDir)
 
        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)
 
    def _fontName(self):
        font = QtGui.QFont()
        font.setFamily(self.fontName.currentText())
        font.setPointSize(int(self.fontSize.value()))
        self.edit.setFont(font)
        self.edit.setFocus()
 
    def _fontSize(self):
        font = QtGui.QFont()
        font.setFamily(self.fontName.currentText())
        font.setPointSize(int(self.fontSize.value()))
        self.edit.setFont(font)
        self.edit.setFocus()
 
    def _toggleDir(self):
        global dir
        if dir == 'rtl':
            option=self.edit.document().defaultTextOption()
            option.setTextDirection(QtCore.Qt.LeftToRight)
            self.edit.document().setDefaultTextOption(option)
            self.edit.setLayoutDirection(QtCore.Qt.LeftToRight) #switch scrollerbar
            dir = 'ltr'
        else:
            option=self.edit.document().defaultTextOption()
            option.setTextDirection(QtCore.Qt.RightToLeft)
            self.edit.document().setDefaultTextOption(option)
            self.edit.setLayoutDirection(QtCore.Qt.RightToLeft) #switch scrollerbar
            dir = 'rtl'
 
    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow", None))
        self.toggleDirBtn.setText(_translate("MainWindow", "Toggle Direction", None))
 
 
if __name__ == "__main__":
    import sys
    app = QtGui.QApplication(sys.argv)
    MainWindow = QtGui.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())

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

# Form implementation generated from reading ui file 'toggleDir.ui'
#
# Created by: PyQt4 UI code generator 4.11.4
#
# WARNING! All changes made in this file will be lost!

from PyQt4 import QtCore, QtGui

dir = 'rtl'

try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s

try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName(_fromUtf8("MainWindow"))
        MainWindow.resize(350, 350)
        MainWindow.setMinimumSize(QtCore.QSize(350, 350))
        MainWindow.setMaximumSize(QtCore.QSize(350, 350))
        self.centralwidget = QtGui.QWidget(MainWindow)
        self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
        self.verticalLayout = QtGui.QVBoxLayout(self.centralwidget)
        self.verticalLayout.setObjectName(_fromUtf8("verticalLayout"))
        self.horizontalLayout = QtGui.QHBoxLayout()
        self.horizontalLayout.setObjectName(_fromUtf8("horizontalLayout"))
        self.fontName = QtGui.QFontComboBox(self.centralwidget)
        self.fontName.setObjectName(_fromUtf8("fontName"))
        self.horizontalLayout.addWidget(self.fontName)
        self.fontSize = QtGui.QSpinBox(self.centralwidget)
        self.fontSize.setProperty("value", 11)
        self.fontSize.setObjectName(_fromUtf8("fontSize"))
        self.horizontalLayout.addWidget(self.fontSize)
        self.verticalLayout.addLayout(self.horizontalLayout)
        self.edit = QtGui.QTextEdit(self.centralwidget)
        self.edit.setObjectName(_fromUtf8("edit"))
        self.edit.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
        self.verticalLayout.addWidget(self.edit)
        self.toggleDirBtn = QtGui.QPushButton(self.centralwidget)
        font = QtGui.QFont()
        font.setPointSize(15)
        self.toggleDirBtn.setFont(font)
        self.toggleDirBtn.setObjectName(_fromUtf8("toggleDirBtn"))
        self.verticalLayout.addWidget(self.toggleDirBtn)
        MainWindow.setCentralWidget(self.centralwidget)
        option=self.edit.document().defaultTextOption()
        option.setTextDirection(QtCore.Qt.RightToLeft)
        self.edit.document().setDefaultTextOption(option)
        self.edit.setLayoutDirection(QtCore.Qt.RightToLeft) #switch scrollerbar
        self.edit.setTabStopWidth(33) #set tab size for editor
        self.fontName.currentFontChanged.connect(self._fontName)
        self.fontSize.valueChanged.connect(self._fontSize)
        self.toggleDirBtn.clicked.connect(self._toggleDir)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)
    
    def _fontName(self):
        font = QtGui.QFont()
        font.setFamily(self.fontName.currentText())
        font.setPointSize(int(self.fontSize.value()))
        self.edit.setFont(font)
        self.edit.setFocus()
    
    def _fontSize(self):
        font = QtGui.QFont()
        font.setFamily(self.fontName.currentText())
        font.setPointSize(int(self.fontSize.value()))
        self.edit.setFont(font)
        self.edit.setFocus()
    
    def _toggleDir(self):
        global dir
        if dir == 'rtl':
            option=self.edit.document().defaultTextOption()
            option.setTextDirection(QtCore.Qt.LeftToRight)
            self.edit.document().setDefaultTextOption(option)
            self.edit.setLayoutDirection(QtCore.Qt.LeftToRight) #switch scrollerbar
            dir = 'ltr'
        else:
            option=self.edit.document().defaultTextOption()
            option.setTextDirection(QtCore.Qt.RightToLeft)
            self.edit.document().setDefaultTextOption(option)
            self.edit.setLayoutDirection(QtCore.Qt.RightToLeft) #switch scrollerbar
            dir = 'rtl'
    
    def retranslateUi(self, MainWindow):
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow", None))
        self.toggleDirBtn.setText(_translate("MainWindow", "Toggle Direction", None))


if __name__ == "__main__":
    import sys
    app = QtGui.QApplication(sys.argv)
    MainWindow = QtGui.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())

To copy to clipboard, switch view to plain text mode