如何向QsciLexerCustom子类添加折叠？

Question

请考虑以下代码段:

import sys
import textwrap
import re

from PyQt5.Qt import *  # noqa

from PyQt5.Qsci import QsciScintilla
from PyQt5.Qsci import QsciLexerCustom

from lark import Lark, inline_args, Transformer


class LexerJson(QsciLexerCustom):

    def __init__(self, parent=None):
        super().__init__(parent)
        self.create_grammar()
        self.create_styles()

    def create_styles(self):
        deeppink = QColor(249, 38, 114)
        khaki = QColor(230, 219, 116)
        mediumpurple = QColor(174, 129, 255)
        mediumturquoise = QColor(81, 217, 205)
        yellowgreen = QColor(166, 226, 46)
        lightcyan = QColor(213, 248, 232)
        darkslategrey = QColor(39, 40, 34)

        styles = {
            0: mediumturquoise,
            1: mediumpurple,
            2: yellowgreen,
            3: deeppink,
            4: khaki,
            5: lightcyan
        }

        for style, color in styles.items():
            self.setColor(color, style)
            self.setPaper(darkslategrey, style)
            self.setFont(self.parent().font(), style)

        self.token_styles = {
            "__COLON": 5,
            "__COMMA": 5,
            "__FALSE1": 0,
            "__LBRACE": 5,
            "__LSQB": 5,
            "__NULL2": 0,
            "__RBRACE": 5,
            "__RSQB": 5,
            "__TRUE0": 0,
            "ESCAPED_STRING": 4,
            "SIGNED_NUMBER": 1,
        }

    def create_grammar(self):
        grammar = '''
            ?start: value
            ?value: object
                  | array
                  | string
                  | SIGNED_NUMBER      -> number
                  | "true"             -> true
                  | "false"            -> false
                  | "null"             -> null
            array  : "[" [value ("," value)*] "]"
            object : "{" [pair ("," pair)*] "}"
            pair   : string ":" value
            string : ESCAPED_STRING
            %import common.ESCAPED_STRING
            %import common.SIGNED_NUMBER
            %import common.WS
            %ignore WS
        '''

        class TreeToJson(Transformer):
            @inline_args
            def string(self, s):
                return s[1:-1].replace('\\"', '"')

            array = list
            pair = tuple
            object = dict
            number = inline_args(float)

            def null(self, _): return None

            def true(self, _): return True

            def false(self, _): return False

        self.lark = Lark(grammar, parser='lalr', transformer=TreeToJson())
        # All tokens: print([t.name for t in self.lark.parser.lexer.tokens])

    def defaultPaper(self, style):
        return QColor(39, 40, 34)

    def language(self):
        return "Json"

    def description(self, style):
        return {v: k for k, v in self.token_styles.items()}.get(style, "")

    def styleText(self, start, end):
        self.startStyling(start)
        text = self.parent().text()[start:end]
        last_pos = 0

        try:
            for token in self.lark.lex(text):
                ws_len = token.pos_in_stream - last_pos
                if ws_len:
                    self.setStyling(ws_len, 0)    # whitespace

                token_len = len(bytearray(token, "utf-8"))
                self.setStyling(
                    token_len, self.token_styles.get(token.type, 0))

                last_pos = token.pos_in_stream + token_len
        except Exception as e:
            print(e)


class EditorAll(QsciScintilla):

    def __init__(self, parent=None):
        super().__init__(parent)

        # Set font defaults
        font = QFont()
        font.setFamily('Consolas')
        font.setFixedPitch(True)
        font.setPointSize(8)
        font.setBold(True)
        self.setFont(font)

        # Set margin defaults
        fontmetrics = QFontMetrics(font)
        self.setMarginsFont(font)
        self.setMarginWidth(0, fontmetrics.width("000") + 6)
        self.setMarginLineNumbers(0, True)
        self.setMarginsForegroundColor(QColor(128, 128, 128))
        self.setMarginsBackgroundColor(QColor(39, 40, 34))
        self.setMarginType(1, self.SymbolMargin)
        self.setMarginWidth(1, 12)

        # Set indentation defaults
        self.setIndentationsUseTabs(False)
        self.setIndentationWidth(4)
        self.setBackspaceUnindents(True)
        self.setIndentationGuides(True)

        # Set folding defaults (http://www.scintilla.org/ScintillaDoc.html#Folding)
        self.setFolding(QsciScintilla.CircledFoldStyle)

        # Set caret defaults
        self.setCaretForegroundColor(QColor(247, 247, 241))
        self.setCaretWidth(2)

        # Set selection color defaults
        self.setSelectionBackgroundColor(QColor(61, 61, 52))
        self.resetSelectionForegroundColor()

        # Set multiselection defaults
        self.SendScintilla(QsciScintilla.SCI_SETMULTIPLESELECTION, True)
        self.SendScintilla(QsciScintilla.SCI_SETMULTIPASTE, 1)
        self.SendScintilla(
            QsciScintilla.SCI_SETADDITIONALSELECTIONTYPING, True)

        lexer = LexerJson(self)
        self.setLexer(lexer)


def main():
    app = QApplication(sys.argv)
    ex = EditorAll()
    ex.setWindowTitle(__file__)
    ex.setText(textwrap.dedent("""\
        {
            "_id": "5b05ffcbcf8e597939b3f5ca",
            "about": "Excepteur consequat commodo esse voluptate aute aliquip ad sint deserunt commodo eiusmod irure. Sint aliquip sit magna duis eu est culpa aliqua excepteur ut tempor nulla. Aliqua ex pariatur id labore sit. Quis sit ex aliqua veniam exercitation laboris anim adipisicing. Lorem nisi reprehenderit ullamco labore qui sit ut aliqua tempor consequat pariatur proident.",
            "address": "665 Malbone Street, Thornport, Louisiana, 243",
            "age": 23,
            "balance": "$3,216.91",
            "company": "BULLJUICE",
            "email": "elisekelley@bulljuice.com",
            "eyeColor": "brown",
            "gender": "female",
            "guid": "d3a6d865-0f64-4042-8a78-4f53de9b0707",
            "index": 0,
            "isActive": false,
            "isActive2": true,
            "latitude": -18.660714,
            "longitude": -85.378048,
            "name": "Elise Kelley",
            "phone": "+1 (808) 543-3966",
            "picture": "http://placehold.it/32x32",
            "registered": "2017-09-30T03:47:40 -02:00",
            "tags": [
                "et",
                "nostrud",
                "in",
                "fugiat",
                "incididunt",
                "labore",
                "nostrud"
            ]
        }\
    """))
    ex.resize(800, 600)
    ex.show()
    sys.exit(app.exec_())


if __name__ == "__main__":
    main()

要运行上面的mcve,你只需要运行 pip install lark-parser PyQt5 QScintilla

我正在试图找出如何修改LexerJson所以符号[ ] { }将支持折叠.当使用现有的类如qscilexercpp.cpp时,折叠行为只是免费提供给你,例如,你只需执行以下操作:

# http://www.scintilla.org/ScintillaDoc.html#Folding
self.setFolding(QsciScintilla.BoxedTreeFoldStyle)

lexer = QsciLexerCPP()
lexer.setFoldAtElse(True)
lexer.setFoldComments(True)
lexer.setFoldCompact(False)
lexer.setFoldPreprocessor(True)
self.setLexer(lexer)

折叠只是免费工作......但是当我使用像我在发布的mcve中做的自定义词法分析器时,我想你必须自己实现这种行为,不幸的是我不知道该怎么做.

那么,这基本上就是问题,你如何在QsciLexerCustom子类上实现折叠？

Answer 1

我无法修复您的词法分析器代码,但我可以为您提供相同的工作示例

import sys
from PyQt5.Qt import *
from PyQt5.Qsci import QsciScintilla, QsciLexerCPP
from PyQt5.Qsci import QsciLexerCustom

if sys.hexversion < 0x020600F0:
     print('python 2.6 or greater is required by this program')
     sys.exit(1)

_sample = """
# Sample config file

this is a junk line

[FirstItem]
Width=100
Height=200
Colour=orange
Info=this is some
     multiline
     text

[SecondItem]
Width=200
Height=300
Colour=green
Info=
     this is some
     multiline
     text
"""


class MainWindow(QMainWindow):
     def __init__(self):
         QMainWindow.__init__(self)
         self.setWindowTitle('Custom Lexer For Config Files')
         self.setGeometry(50, 200, 400, 400)
         self.editor = QsciScintilla(self)
         self.editor.setUtf8(True)
         self.editor.setMarginWidth(2, 15)
         self.editor.setFolding(True)
         self.setCentralWidget(self.editor)
         self.lexer = ConfigLexer(self.editor)
         self.editor.setLexer(self.lexer)
         self.editor.setText(_sample)


class ConfigLexer(QsciLexerCustom):
     def __init__(self, parent):
         QsciLexerCustom.__init__(self, parent)
         self._styles = {
             0: 'Default',
             1: 'Comment',
             2: 'Section',
             3: 'Key',
             4: 'Assignment',
             5: 'Value',
             }
         for key,value in self._styles.items():
             setattr(self, value, key)
         self._foldcompact = True

     def foldCompact(self):
         return self._foldcompact

     def setFoldCompact(self, enable):
         self._foldcompact = bool(enable)

     def language(self):
         return 'Config Files'

     def description(self, style):
         return self._styles.get(style, '')

     def defaultColor(self, style):
         if style == self.Default:
             return QColor('#000000')
         elif style == self.Comment:
             return QColor('#A0A0A0')
         elif style == self.Section:
             return QColor('#CC6600')
         elif style == self.Key:
             return QColor('#0000CC')
         elif style == self.Assignment:
             return QColor('#CC0000')
         elif style == self.Value:
             return QColor('#00CC00')
         return QsciLexerCustom.defaultColor(self, style)

     def defaultPaper(self, style):
         if style == self.Section:
             return QColor('#FFEECC')
         return QsciLexerCustom.defaultPaper(self, style)

     def defaultEolFill(self, style):
         if style == self.Section:
             return True
         return QsciLexerCustom.defaultEolFill(self, style)

     def defaultFont(self, style):
         if style == self.Comment:
             if sys.platform in ('win32', 'cygwin'):
                 return QFont('Comic Sans MS', 9)
             return QFont('Bitstream Vera Serif', 9)
         return QsciLexerCustom.defaultFont(self, style)

     def styleText(self, start, end):
         editor = self.editor()
         if editor is None:
             return

         SCI = editor.SendScintilla
         GETFOLDLEVEL = QsciScintilla.SCI_GETFOLDLEVEL
         SETFOLDLEVEL = QsciScintilla.SCI_SETFOLDLEVEL
         HEADERFLAG = QsciScintilla.SC_FOLDLEVELHEADERFLAG
         LEVELBASE = QsciScintilla.SC_FOLDLEVELBASE
         NUMBERMASK = QsciScintilla.SC_FOLDLEVELNUMBERMASK
         WHITEFLAG = QsciScintilla.SC_FOLDLEVELWHITEFLAG
         set_style = self.setStyling

         source = ''
         if end > editor.length():
             end = editor.length()
         if end > start:
             source = bytearray(end - start)
             SCI(QsciScintilla.SCI_GETTEXTRANGE, start, end, source)
         if not source:
             return

         compact = self.foldCompact()

         index = SCI(QsciScintilla.SCI_LINEFROMPOSITION, start)
         if index > 0:
             pos = SCI(QsciScintilla.SCI_GETLINEENDPOSITION, index - 1)
             state = SCI(QsciScintilla.SCI_GETSTYLEAT, pos)
         else:
             state = self.Default

         self.startStyling(start, 0x1f)

         for line in source.splitlines(True):
             length = len(line)
             if length == 1:
                 whitespace = compact
                 state = self.Default
             else:
                 whitespace = False
                 firstchar = chr(line[0])
                 if firstchar in '#;':
                     state = self.Comment
                 elif firstchar == '[':
                     state = self.Section
                 elif firstchar in ' \t':
                     if state == self.Value or state == self.Assignment:
                         state = self.Value
                     else:
                         whitespace = compact and line.isspace()
                         state = self.Default
                 else:
                     pos = line.find(b'=')
                     if pos < 0:
                         pos = line.find(b':')
                     else:
                         tmp = line.find(b':', 0, pos)
                         if tmp >= 0:
                             pos = tmp
                     if pos > 0:
                         set_style(pos, self.Key)
                         set_style(1, self.Assignment)
                         length = length - pos - 1
                         state = self.Value
                     else:
                         state = self.Default
             set_style(length, state)

             if state == self.Section:
                 level = LEVELBASE | HEADERFLAG
             elif index > 0:
                 lastlevel = SCI(GETFOLDLEVEL, index - 1)
                 if lastlevel & HEADERFLAG:
                     level = LEVELBASE + 1
                 else:
                     level = lastlevel & NUMBERMASK
             else:
                 level = LEVELBASE

             if whitespace:
                 level |= WHITEFLAG
             if level != SCI(GETFOLDLEVEL, index):
                 SCI(SETFOLDLEVEL, index, level)

             index += 1

         if index > 0:
             lastlevel = SCI(GETFOLDLEVEL, index - 1)
             if lastlevel & HEADERFLAG:
                 level = LEVELBASE + 1
             else:
                 level = lastlevel & NUMBERMASK
         else:
             level = LEVELBASE

         lastlevel = SCI(GETFOLDLEVEL, index)
         SCI(SETFOLDLEVEL, index, level | lastlevel & ~NUMBERMASK)


if __name__ == "__main__":
     app = QApplication(sys.argv)
     win = MainWindow()
     win.show()
     sys.exit(app.exec_())

关键的东西发生在这里

             if state == self.Section:
                 level = LEVELBASE | HEADERFLAG
             elif index > 0:
                 lastlevel = SCI(GETFOLDLEVEL, index - 1)
                 if lastlevel & HEADERFLAG:
                     level = LEVELBASE + 1
                 else:
                     level = lastlevel & NUMBERMASK
             else:
                 level = LEVELBASE

             if whitespace:
                 level |= WHITEFLAG
             if level != SCI(GETFOLDLEVEL, index):
                 SCI(SETFOLDLEVEL, index, level)

             index += 1

         if index > 0:
             lastlevel = SCI(GETFOLDLEVEL, index - 1)
             if lastlevel & HEADERFLAG:
                 level = LEVELBASE + 1
             else:
                 level = lastlevel & NUMBERMASK
         else:
             level = LEVELBASE

         lastlevel = SCI(GETFOLDLEVEL, index)
         SCI(SETFOLDLEVEL, index, level | lastlevel & ~NUMBERMASK)

PS:来自https://github.com/pingf/toys/blob/f808e7c4ed1a76db4800c8e1ee6d163242df52cc/src/201403/customLexer2.py的致谢