如何在 QTextEdit 中滚动行号答案

【问题标题】：How to scroll line numbers in a QTextEdit如何在 QTextEdit 中滚动行号
【发布时间】：2016-01-24 11:10:03
【问题描述】：

这是我的代码：

import sys
from PySide.QtCore import *
from PySide.QtGui import *

class Editor(QPlainTextEdit):
    def __init__(self, parent):
        super(Editor, self).__init__()
        self.setPlainText( u'apple, banana\norange\nblah blah\n\nOh yeah!....\n'*2 )
        self.setParent( parent )

        self.setWordWrapMode( QTextOption.NoWrap )
        self.setViewportMargins( 50,0,0,0 )

        QObject.connect( self, SIGNAL("textChanged()"), self.repainting )

    def repainting(self) : self.parent().update()

class WinE(QMainWindow):
    def __init__(self, font=QFont( 'Monospace', 12 )):
        super(WinE, self).__init__()

        self.font = font
        self.font.setFixedPitch( True )

        self.ce = Editor( self )
        self.ce.setFont( self.font )

        self.setWindowTitle('Code Editor')

        self.textr = QRect( 3, 5, self.ce.childrenRect().x() -12, self.ce.childrenRect().height() )

        self.setGeometry( QRect(800, 840, 351, 250) )
        self.setCentralWidget( self.ce )

        self.show()

    def paintEvent(self, event):

        qp = QPainter   ()
        qp.begin        ( self )
        self.drawLiNums ( qp )
        qp.end          ()

    def drawLiNums(self, qp):

        qp.setPen       ( QColor(255, 255, 255) )
        qp.setFont      ( self.font )
        qp.drawText     ( self.textr, Qt.AlignRight, self.lineNumeration() ) 

    def lineNumeration(self):

        return ''.join( [str(n+1) +'\n' for n in range( len(self.ce.toPlainText().splitlines(False)) )] )

def main():

    app = QApplication(sys.argv)
    ex = WinE()
    sys.exit(app.exec_())

if __name__ == '__main__': main()

Editor 出现数字，添加新行时数字会更新。但是当它到达小部件的末尾时，文本在输入时继续滚动，但行号停止更新，并且行号区域没有任何滚动！

【问题讨论】：

标签： python qt scroll pyside qtextedit

【解决方案1】：

希望这能解决您的问题！
每次向下滚动文本时，我都会简单地调用parent().update()。我在第一条可见线开始 lineNumeration (line=block in qt)
最良好的祝愿，MrP :)

import sys
from PySide.QtCore import *
from PySide.QtGui import *

class Editor(QPlainTextEdit):
    def __init__(self, parent):
        super(Editor, self).__init__()
        self.setPlainText( u'apple, banana\norange\nblah blah\n\nOh yeah!....\n'*6 )
        self.setParent( parent )

        self.setWordWrapMode( QTextOption.NoWrap )
        self.setViewportMargins( 50,0,0,0 )

        QObject.connect( self, SIGNAL("textChanged()"), self.repainting )

    def repainting(self):
        self.parent().update()

    def scrollContentsBy(self, *args, **kwargs):
        self.parent().update()
        return QPlainTextEdit.scrollContentsBy(self, *args, **kwargs)

class WinE(QMainWindow):
    def __init__(self, font=QFont( 'Monospace', 12 )):
        super(WinE, self).__init__()

        self.font = font
        self.font.setFixedPitch( True )

        self.ce = Editor( self )
        self.ce.setFont( self.font )

        self.setWindowTitle('Code Editor')

        self.textr = QRect( 3, 5, self.ce.childrenRect().x() -12, self.ce.childrenRect().height() )

        self.setGeometry( QRect(800, 840, 351, 250) )
        self.setCentralWidget( self.ce )

        self.show()

    def paintEvent(self, event):

        qp = QPainter   ()
        qp.begin        ( self )
        self.drawLiNums ( qp )
        qp.end          ()

    def drawLiNums(self, qp):

        qp.setPen       ( QColor(255, 255, 255) )
        qp.setFont      ( self.font )
        qp.drawText     ( self.textr, Qt.AlignRight, self.lineNumeration() )

    def lineNumeration(self):
        offset=self.ce.firstVisibleBlock().firstLineNumber()
        return ''.join(str(i)+"\n" for i in range(offset+1, self.ce.blockCount()+1))

def main():

    app = QApplication(sys.argv)
    ex = WinE()
    sys.exit(app.exec_())

if __name__ == '__main__': main()

【讨论】：