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c++qtqlineedit

Retain the cursor position in QTextEdit

I have a QTextEdit control. It has a maximum limit (maximum number of characters it can hold). To implement this I have connected a slot to the textChanged() signal which removes the extra character when the total number of characters exceeds the allowed maximum.

With this I have some problems dealing with the cursor position. Can anyone tell me how to retain the cursor position in QTextEdit?

Solution

  • On your slot:

    If num of chars exceeds maximum:

    Ask the QTextEdit for the Cursor:

    QTextCursor QTextEdit::textCursor() const

    Set the return value as your textEdit cursor (cause it returns a copy). From doc:

    Returns a copy of the QTextCursor that represents the currently visible cursor. Note that > changes on the returned cursor do not affect QTextEdit's cursor; use setTextCursor() to > update the visible cursor.

    void QTextEdit::setTextCursor(const QTextCursor & cursor)

    Ask the cursor to delete last char

    void QTextCursor::deletePreviousChar()

    (Edit)as code:

    QTextCursor  cursor = ui->textEdit->textCursor();
ui->textEdit->setTextCursor( cursor );
cursor.deletePreviousChar();