diff options
| author | Sze Howe Koh <szehowe.koh@gmail.com> | 2023-06-04 23:01:04 +0800 |
|---|---|---|
| committer | Volker Hilsheimer <volker.hilsheimer@qt.io> | 2023-06-07 16:46:56 +0000 |
| commit | 5a2474b2dd0472948c53b16c4bf566db489dcfb9 (patch) | |
| tree | b24ab31a466ac2eef182e46a8cd8b228bce405db | |
| parent | 526744ba6536175f9a19ffdf6ff1ee068f9522a4 (diff) | |
Doc: Clarify how to use QPainter with QTextEdit
The documentation suggests that it is possible to reimplement
QTextEdit::paintEvent(), but doing so might produce cryptic runtime
warnings:
QWidget::paintEngine: Should no longer be called
QPainter::begin: Paint device returned engine == 0, type: 1
The correct way to reimplement this function is noted under
QAbstractScrollArea::paintEvent(). This patch updates the note and
copies it to QTextEdit for clarity.
Pick-to: 6.6 6.5 6.2
Change-Id: Ib7d8dadeb2358475bcdb0b2e624857700f9a004e
Reviewed-by: Safiyyah Moosa <safiyyah.moosa@qt.io>
Reviewed-by: Andreas Eliasson <andreas.eliasson@qt.io>
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
| -rw-r--r-- | src/widgets/widgets/qabstractscrollarea.cpp | 2 | ||||
| -rw-r--r-- | src/widgets/widgets/qtextedit.cpp | 2 |
2 files changed, 3 insertions, 1 deletions
diff --git a/src/widgets/widgets/qabstractscrollarea.cpp b/src/widgets/widgets/qabstractscrollarea.cpp index 05d9c18f07..0692e28f67 100644 --- a/src/widgets/widgets/qabstractscrollarea.cpp +++ b/src/widgets/widgets/qabstractscrollarea.cpp @@ -1100,7 +1100,7 @@ void QAbstractScrollArea::resizeEvent(QResizeEvent *) This event handler can be reimplemented in a subclass to receive paint events (passed in \a event), for the viewport() widget. - \note If you open a painter, make sure to open it on the viewport(). + \note If you create a QPainter, it must operate on the viewport(). \sa QWidget::paintEvent() */ diff --git a/src/widgets/widgets/qtextedit.cpp b/src/widgets/widgets/qtextedit.cpp index 6782b37911..b4b16120ea 100644 --- a/src/widgets/widgets/qtextedit.cpp +++ b/src/widgets/widgets/qtextedit.cpp @@ -1599,6 +1599,8 @@ void QTextEditPrivate::paint(QPainter *p, QPaintEvent *e) This event handler can be reimplemented in a subclass to receive paint events passed in \a event. It is usually unnecessary to reimplement this function in a subclass of QTextEdit. +\note If you create a QPainter, it must operate on the \l{QAbstractScrollArea::}{viewport()}. + \warning The underlying text document must not be modified from within a reimplementation of this function. */ |