class MyProgEdit(QPlainTextEdit):
    lastBGcolor=None
    MainScreen=None
    class PythonHighlighter(QSyntaxHighlighter):
        Rules = []
        def __init__(self, parent=None):
            super(MyProgEdit.PythonHighlighter, self).__init__(parent)
            keywordFormat = QTextCharFormat()
            keywordFormat.setForeground(Qt.darkBlue)
            keywordFormat.setFontWeight(QFont.Bold)
            for pattern in ((r"\band\b", r"\bas\b", r"\bassert\b",
                    r"\bbreak\b", r"\bclass\b", r"\bcontinue\b",
                    r"\bdef\b", r"\bdel\b", r"\belif\b", r"\belse\b",
                    r"\bexcept\b", r"\bexec\b", r"\bfinally\b", r"\bfor\b",
                    r"\bfrom\b", r"\bglobal\b", r"\bif\b", r"\bimport\b",
                    r"\bin\b", r"\bis\b", r"\blambda\b", r"\bnot\b",
                    r"\bor\b", r"\bpass\b", r"\bprint\b", r"\braise\b",
                    r"\breturn\b", r"\btry\b", r"\bwhile\b", r"\bwith\b",
                    r"\byield\b")):
                MyProgEdit.PythonHighlighter.Rules.append((QRegExp(pattern),
                                               keywordFormat))
            commentFormat = QTextCharFormat()
            commentFormat.setForeground(Qt.darkGreen)
            commentFormat.setFontItalic(True)
            MyProgEdit.PythonHighlighter.Rules.append((QRegExp(r"#.*"),
                                            commentFormat))
            self.stringFormat = QTextCharFormat()
            self.stringFormat.setForeground(Qt.red)
            stringRe = QRegExp(r"""(?:'[^']*'|"[^"]*")""")
            stringRe.setMinimal(True)
            MyProgEdit.PythonHighlighter.Rules.append((stringRe, self.stringFormat))
            self.stringRe = QRegExp(r"""(:?"["]".*"["]"|'''.*''')""")
            self.stringRe.setMinimal(True)
            MyProgEdit.PythonHighlighter.Rules.append((self.stringRe,
                                            self.stringFormat))
            self.tripleSingleRe = QRegExp(r"""'''(?!")""")
            self.tripleDoubleRe = QRegExp(r'''"""(?!')''')


        def highlightBlock(self, text):
            NORMAL, TRIPLESINGLE, TRIPLEDOUBLE = range(3)

            for regex, format in MyProgEdit.PythonHighlighter.Rules:
                i = text.indexOf(regex)
                while i >= 0:
                    length = regex.matchedLength()
                    self.setFormat(i, length, format)
                    i = text.indexOf(regex, i + length)

            self.setCurrentBlockState(NORMAL)
            if text.indexOf(self.stringRe) != -1:
                return
            for i, state in ((text.indexOf(self.tripleSingleRe),
                              TRIPLESINGLE),
                             (text.indexOf(self.tripleDoubleRe),
                              TRIPLEDOUBLE)):
                if self.previousBlockState() == state:
                    if i == -1:
                        i = text.length()
                        self.setCurrentBlockState(state)
                    self.setFormat(0, i + 3, self.stringFormat)
                elif i > -1:
                    self.setCurrentBlockState(state)
                    self.setFormat(i, text.length(), self.stringFormat)
    def __init__(self, txt):
        QPlainTextEdit.__init__(self, txt)
        font = QFont("Courier New", 10)
        font.setFixedPitch(True)
        self.setFont(font)
        self.highlighter = MyProgEdit.PythonHighlighter(self.document())
        self.setSizePolicy(QSizePolicy.Expanding,QSizePolicy.Expanding )
    def text(self):
        return self.toPlainText()
    def event(self, event):
        if event.type() == QEvent.KeyPress and \
           event.key() == Qt.Key_Tab:
            cursor = self.textCursor()
            cursor.insertText("    ")
            return True
        return QPlainTextEdit.event(self, event)
    def setText(self, text):
        self.setPlainText(text)
    def focusInEvent(self, ev):
        QPlainTextEdit.focusInEvent(self, ev)
        if self.lastBGcolor==None: self.lastBGcolor=self.palette().color(QPalette.Base)
        palette = QPalette()
        palette.setBrush(QPalette.Active, QPalette.Base, QBrush(ActiveBGcolor))
        self.setPalette(palette)
    def focusOutEvent(self, ev):
        QPlainTextEdit.focusOutEvent(self, ev)
        if self.lastBGcolor<>None:
            palette = QPalette()
            palette.setBrush(QPalette.Active, QPalette.Base, QBrush(self.lastBGcolor))
            self.setPalette(palette)