python - QPlainTextEdit 是 RightToLeft 但显示 LeftToRight

Question

我使用QPlainTextEdit创建了一个 View 并设置了setLayoutDirection(QtCore.Qt.RightToLeft)。 self.plaintxt.isRightToLeft() 的输出为 1，但在纯 TextView 中，波斯语和英语文本从左侧显示。我的代码发生了什么？

代码:

import sys, re

from PyQt5 import QtCore
from PyQt5.QtWidgets import QApplication, QLabel, QLineEdit, QMainWindow, QPushButton, QFileSystemModel, QTreeView, \
    QFileDialog, QComboBox, QPlainTextEdit
from PyQt5.QtCore import pyqtSlot


class App(QMainWindow):

    def __init__(self):
        super(App, self).__init__()

        self.title = 'by PyQt5 and python 3.7'
        self.left = 10
        self.top = 10
        self.width = 1000
        self.height = 500

        self.initUI()

    def initUI(self):
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top, self.width, self.height)

        self.btn_browse = QPushButton('Browse', self)
        self.btn_browse.move(50, 20)
        self.btn_browse.clicked.connect(self.on_click)

        self.textbox = QLineEdit(self)
        self.textbox.move(170, 20)
        self.textbox.resize(280, 40)
        self.textbox.setAlignment(QtCore.Qt.AlignRight) # It is in right.

        self.page_view = QPlainTextEdit(self)
        self.page_view.move(20, 100)
        self.page_view.resize(800, 400)
        self.page_view.setLayoutDirection(QtCore.Qt.RightToLeft) # It is not in right.

        self.show()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = App()
    sys.exit(app.exec_())

Answer 1

QWidget.setLayoutDirection不再影响QTextEdit、QLineEdit和基于它们的小部件的文本布局方向(Qt.LeftToRight或Qt.RightToLeft)。

要以编程方式强制文本方向，您可以使用不同 textDirection 属性的新 QTextOption 来更改与该小部件关联的 QTextDocument 的 defaultTextOption。

QTextDocument *QPlainTextEdit::document() const

Returns a pointer to the underlying document.

void QTextDocument::setDefaultTextOption(const QTextOption &option)

Sets the default text option to option.

self.page_view.document().setDefaultTextOption(QTextOption(Qt.AlignRight))