C++ QTextCursor::deleteChar方法代码示例

QTextDocument *Exporter::prepareTextDoc(QTextDocument *textDoc)
{



    QTextDocument *textDocument = textDoc->clone(this);

    //    textDocument->setDefaultStyleSheet("p, li { white-space: pre-wrap; } p{line-height: 2em; font-family:'Liberation Serif'; font-size:19pt;margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:72px;}");

    //cut blank spaces at the begining and end :



    QTextCursor *tCursor = new QTextCursor(textDocument);
    tCursor->movePosition(QTextCursor::Start, QTextCursor::MoveAnchor,1);
    tCursor->movePosition(QTextCursor::NextCharacter, QTextCursor::KeepAnchor,1);

    while(tCursor->selectedText() == " "){
        tCursor->deleteChar();
        tCursor->movePosition(QTextCursor::NextCharacter, QTextCursor::KeepAnchor,1);
    }

    tCursor->movePosition(QTextCursor::End, QTextCursor::MoveAnchor,1);
    tCursor->movePosition(QTextCursor::PreviousCharacter, QTextCursor::KeepAnchor,1);

    while(tCursor->selectedText() == " "){
        tCursor->deleteChar();
        tCursor->movePosition(QTextCursor::PreviousCharacter, QTextCursor::KeepAnchor,1);
    }

    //set text config :

    QTextBlockFormat blockFormat;
    //    blockFormat.setBottomMargin(0);
    //    blockFormat.setTopMargin(0);
    //    blockFormat.setTextIndent(72);
    blockFormat.setLineHeight(200, QTextBlockFormat::ProportionalHeight);
    blockFormat.setAlignment(Qt::AlignJustify);
    //    QTextCharFormat charFormat;
    //    charFormat.setFontPointSize(12);
    //    charFormat.setFontFamily("Courrier");

    tCursor->select(QTextCursor::Document);
    tCursor->mergeBlockFormat(blockFormat);
    //    tCursor->mergeBlockCharFormat(charFormat);


    QRegExp reg("-qt-paragraph-type:.*;|margin-top:.*;|margin-bottom:.*;|margin-left:.*;|margin-right:.*;|-qt-block-indent:.*;|text-indent:.*;|font-family:.*;|font-size:.*;");
    reg.setMinimal(true);
    textDocument->setHtml(textDocument->toHtml().remove(reg));



    return textDocument;
}

void CodeEditor::deleteLine(){
    QTextCursor selection = getSelectedLines();
    selection.beginEditBlock();
    selection.removeSelectedText();
    selection.deleteChar();
    selection.endEditBlock();
}

bool AutoCompleter::autoBackspace(QTextCursor &cursor)
{
    m_allowSkippingOfBlockEnd = false;

    if (!m_autoParenthesesEnabled)
        return false;

    int pos = cursor.position();
    if (pos == 0)
        return false;
    QTextCursor c = cursor;
    c.setPosition(pos - 1);

    QTextDocument *doc = cursor.document();
    const QChar lookAhead = doc->characterAt(pos);
    const QChar lookBehind = doc->characterAt(pos - 1);
    const QChar lookFurtherBehind = doc->characterAt(pos - 2);

    const QChar character = lookBehind;
    if (character == QLatin1Char('(') || character == QLatin1Char('[')) {
        QTextCursor tmp = cursor;
        TextBlockUserData::findPreviousBlockOpenParenthesis(&tmp);
        int blockStart = tmp.isNull() ? 0 : tmp.position();
        tmp = cursor;
        TextBlockUserData::findNextBlockClosingParenthesis(&tmp);
        int blockEnd = tmp.isNull() ? (cursor.document()->characterCount()-1) : tmp.position();
        QChar openChar = character;
        QChar closeChar = (character == QLatin1Char('(')) ? QLatin1Char(')') : QLatin1Char(']');

        int errors = 0;
        int stillopen = 0;
        countBrackets(cursor, blockStart, blockEnd, openChar, closeChar, &errors, &stillopen);
        int errorsBeforeDeletion = errors + stillopen;
        errors = 0;
        stillopen = 0;
        countBrackets(cursor, blockStart, pos - 1, openChar, closeChar, &errors, &stillopen);
        countBrackets(cursor, pos, blockEnd, openChar, closeChar, &errors, &stillopen);
        int errorsAfterDeletion = errors + stillopen;

        if (errorsAfterDeletion < errorsBeforeDeletion)
            return false; // insertion fixes parentheses or bracket errors, do not auto complete
    }

    // ### this code needs to be generalized
    if    ((lookBehind == QLatin1Char('(') && lookAhead == QLatin1Char(')'))
        || (lookBehind == QLatin1Char('[') && lookAhead == QLatin1Char(']'))
        || (lookBehind == QLatin1Char('"') && lookAhead == QLatin1Char('"')
            && lookFurtherBehind != QLatin1Char('\\'))
        || (lookBehind == QLatin1Char('\'') && lookAhead == QLatin1Char('\'')
            && lookFurtherBehind != QLatin1Char('\\'))) {
        if (! isInComment(c)) {
            cursor.beginEditBlock();
            cursor.deleteChar();
            cursor.deletePreviousChar();
            cursor.endEditBlock();
            return true;
        }
    }
    return false;
}

bool ScCodeEditor::removeMatchingTokens()
{
    QTextCursor cursor = textCursor();
    QTextDocument *document = cursor.document();
    int cursorPosition = cursor.position();
    if (cursorPosition == 0)
        return false;

    QChar previousChar = document->characterAt(cursorPosition-1);
    QChar nextChar;
    if (previousChar == '{')
        nextChar = '}';
    else if (previousChar == '[')
        nextChar = ']';
    else if (previousChar == '(')
        nextChar = ')';
    else if (previousChar == '\'' || previousChar == '"')
        nextChar = previousChar;
    else
        return false;

    if (document->characterAt(cursorPosition) != nextChar)
        return false;

    cursor.beginEditBlock();
    cursor.deletePreviousChar();
    cursor.deleteChar();
    cursor.endEditBlock();

    setTextCursor(cursor);
    return true;
}

void CodeEditor::insertCompletion(const QString& completion){
    if (completer_->widget() != this){
        return;
    }
    QTextCursor tc = textCursor();

    //Delete the characters that the user has entered as it might be in
    //wrong case, and insert entire completion word.
    tc.movePosition(QTextCursor::StartOfWord);
    int toDelete = completer_->completionPrefix().length();
    for(int i=0;i<toDelete;i++){
        tc.deleteChar();
    }
    tc.insertText(completion);
    setTextCursor(tc);

    /*
    //original code, insert only missing characters and keep the characters
    //the user has already entered.
    int extra = completion.length() - completer_->completionPrefix().length();
    tc.movePosition(QTextCursor::Left);
    tc.movePosition(QTextCursor::EndOfWord);
    tc.insertText(completion.right(extra));
    setTextCursor(tc);
    */
}

void	QsvTextOperationsWidget::on_replaceOldText_returnPressed()
{
	if (QApplication::keyboardModifiers().testFlag(Qt::ControlModifier) ||
	    QApplication::keyboardModifiers().testFlag(Qt::AltModifier) ||
	    QApplication::keyboardModifiers().testFlag(Qt::ShiftModifier) ) {
		on_replaceAll_clicked();
		showReplace();
		return;
	}

	QTextCursor c = m_searchCursor;
	QTextDocument *doc = getTextDocument();
	if (!doc){
		qDebug("%s:%d - no document found, using a wrong class? wrong parent?", __FILE__,__LINE__);
		return;
	}
	c = doc->find( replaceFormUi->findText->text(), c, getReplaceFlags() );
	if (c.isNull())
		return;

	int start = c.selectionStart();
	int end   = c.selectionEnd();
	c.beginEditBlock();
	c.deleteChar();
	c.insertText( replaceFormUi->replaceText->text() );
	c.setPosition(start,QTextCursor::KeepAnchor);
	c.setPosition(end  ,QTextCursor::MoveAnchor);
	c.endEditBlock();
	setTextCursor( c );

	// is there any other apperance of this text?
	m_searchCursor = c;
	updateReplaceInput();
}

void TextProcessor::textChangeEvent() {
	if (autoInsertion_)
		return;

	QTextCursor c = edit_->textCursor();
	if (c.atBlockStart()) {
		QTextBlock bl = c.block();
		QTextBlock prevBl = bl.previous();
		if (bl.isValid() && prevBl.isValid()) {

			//	ensure that cursor was moved from the previous row
			if (lastRow_ - 1 != preLastRow_)
				return;

			QString text = bl.text();
			QString prevText = prevBl.text();
			if (/*text.isEmpty() &&*/ !prevText.isEmpty()) {
				int lineBeginIndex = prevText.indexOf(QRegExp("[^ \t]"));
				QString lineBegin = prevText.left(lineBeginIndex);

				autoInsertion_ = true;
				while (bl.text().startsWith('\t') || bl.text().startsWith(' ')) {
					c.deleteChar();
				}
				c.insertText(lineBegin);
				autoInsertion_ = false;
			}
		}
	}
}

QTextDocument *Exporter::prepareNoteDoc(QTextDocument *noteDoc)
{
    QTextDocument *textDocument = noteDoc->clone(this);




    //cut blank spaces at the begining and end :



    QTextCursor *tCursor = new QTextCursor(textDocument);
    tCursor->movePosition(QTextCursor::Start, QTextCursor::MoveAnchor,1);
    tCursor->movePosition(QTextCursor::NextCharacter, QTextCursor::KeepAnchor,1);

    while(tCursor->selectedText() == " "){
        tCursor->deleteChar();
        tCursor->movePosition(QTextCursor::NextCharacter, QTextCursor::KeepAnchor,1);
    }

    tCursor->movePosition(QTextCursor::End, QTextCursor::MoveAnchor,1);
    tCursor->movePosition(QTextCursor::PreviousCharacter, QTextCursor::KeepAnchor,1);

    while(tCursor->selectedText() == " "){
        tCursor->deleteChar();
        tCursor->movePosition(QTextCursor::PreviousCharacter, QTextCursor::KeepAnchor,1);
    }

    //set text config :

    QTextBlockFormat blockFormat;
    blockFormat.setBottomMargin(0);
    blockFormat.setTopMargin(0);
    blockFormat.setTextIndent(72);
    blockFormat.setLineHeight(200, QTextBlockFormat::ProportionalHeight);
    blockFormat.setAlignment(Qt::AlignJustify);
    QTextCharFormat charFormat;
    charFormat.setFontPointSize(12);
    charFormat.setFontFamily("Courrier");

    tCursor->select(QTextCursor::Document);
    tCursor->mergeBlockCharFormat(charFormat);
    tCursor->mergeBlockFormat(blockFormat);


    return textDocument;
}

void
SimpleRichTextEdit::deleteText()
{
	QTextCursor cursor = textCursor();
	if(cursor.hasSelection())
		cursor.removeSelectedText();
	else
		cursor.deleteChar();
}

QTextCursor CodeEditor::deleteCurrentLine()
{
    QTextCursor currentPos = textCursor();
    textCursor().beginEditBlock();
    currentPos.select(QTextCursor::BlockUnderCursor);

    if (currentPos.selectedText() == ""){
        if (currentPos.selectionStart() == 0){
            currentPos.deleteChar();
        }else{
            currentPos.deletePreviousChar();
        }
        currentPos.removeSelectedText();
    }
    else{
        currentPos.removeSelectedText();
        if (currentPos.selectionStart() == 0)
            currentPos.deleteChar();
    }
    return currentPos;
}

void CCodeEditor::_DeleteCurrentLine()
{
	QTextCursor currentCursor = this->textCursor();
	currentCursor.select(QTextCursor::BlockUnderCursor);
	currentCursor.removeSelectedText();
	++m_textChangeTime;
	if (currentCursor.atStart())
	{
		currentCursor.deleteChar();
		++m_textChangeTime;
	}
}

void XTextEdit::sCorrectWord()
{
   QAction *action = qobject_cast<QAction *>(sender());
   if (action)
   {
      QString replacement = action->text();
      QTextCursor cursor = cursorForPosition(_lastPos);
      cursor.select(QTextCursor::WordUnderCursor);
      cursor.deleteChar();
      cursor.insertText(replacement);
      _highlighter->rehighlight();
   }
}

void ChatMessageArea::setHtml(const QString& html) {
    // Create format with updated line height
    QTextBlockFormat format;
    format.setLineHeight(CHAT_MESSAGE_LINE_HEIGHT, QTextBlockFormat::ProportionalHeight);

    // Possibly a bug in QT, the format won't take effect if `insertHtml` is used first.  Inserting a space and deleting
    // it after ensures the format is applied.
    QTextCursor cursor = textCursor();
    cursor.setBlockFormat(format);
    cursor.insertText(" ");
    cursor.insertHtml(html);
    cursor.setPosition(0);
    cursor.deleteChar();
}

/**
 * Deletes the current line
 */
void HaiQTextEdit::delete_current_line() {
    QTextCursor cursor = textCursor();
    cursor.beginEditBlock();
    cursor.clearSelection();
    cursor.movePosition(QTextCursor::StartOfLine);
    int pos(cursor.position());
    cursor.select(QTextCursor::LineUnderCursor);
    // remove line (and line feed char)
    cursor.removeSelectedText();
    cursor.deleteChar();
    // goto start of next line
    cursor.setPosition(pos);
    cursor.endEditBlock();
}

int
QUimTextUtil::deleteSelectionTextInQTextEdit( enum UTextOrigin origin,
                                              int former_req_len,
                                              int latter_req_len )
{
    QTextEdit *edit = static_cast<QTextEdit *>( mWidget );
    QTextCursor cursor = edit->textCursor();
    if ( ! cursor.hasSelection() )
        return -1;

    bool cursor_at_beginning = false;
    int current = cursor.position();
    int start = cursor.selectionStart();
    if ( current == start )
        cursor_at_beginning = true;

    QString text = cursor.selectedText();
    int len = text.length();
    int end = start + len;
    if ( origin == UTextOrigin_Beginning ||
         ( origin == UTextOrigin_Cursor && cursor_at_beginning ) ) {
        if ( latter_req_len >= 0 ) {
            if ( len > latter_req_len )
                end = start + latter_req_len;
        } else {
            if (! ( ~latter_req_len
                    & ( ~UTextExtent_Line | ~UTextExtent_Full ) ) )
                return -1;
        }
    } else if ( origin == UTextOrigin_End ||
                ( origin == UTextOrigin_Cursor && !cursor_at_beginning ) ) {
        if ( former_req_len >= 0 ) {
            if ( len > former_req_len )
                start = end - former_req_len;
        } else {
            if (! ( ~former_req_len
                    & ( ~UTextExtent_Line | ~UTextExtent_Full ) ) )
                return -1;
        }
    } else {
        return -1;
    }
    cursor.setPosition( start );
    cursor.setPosition( end, QTextCursor::KeepAnchor );
    edit->setTextCursor( cursor );
    cursor.deleteChar();

    return 0;
}