resize QTextEdit

[maartenS]

You're right, I messed up with textArea->size() and textArea->viewport()->size()...
The six points is the difference in size between the textArea and the viewport of it, I guess.

In the meantime I fixed the other problems as well:

I centred the QTextArea in the centre of the QScrollArea by:

scrollArea->setAlignment(Qt::AlignCenter);

scrollArea->setAlignment(Qt::AlignCenter);

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removing:

scrollArea->setAutoFillBackground(true);

scrollArea->setAutoFillBackground(true);

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fixed the problem with the background of the scrollbar.

Now I'm wondering how I can scale the contents of the QTextEdit. I tried using zoomIn and zoomOut but I can't get the scaling the same proportions as the scaling of the QTextEdit. Is it possible to scale text from a QTextEdit to a certain percentage?

[codebehind]

i haven't used it yet, but i think you should use void QFont::setStretch ( int factor )

[codebehind]

void QFont::setStretch ( int factor )

[maartenS]

void QFont::setStretch ( int factor )

Thanks! I'll try that one!

[maartenS]

Trying

QFont currentFont = textArea->font();
   currentFont.setStretch(125)

QFont currentFont = textArea->font();
   currentFont.setStretch(125)

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doesn't have any effect.
I tried this:

qreal currentFontPointSize = textArea->font().pointSize();
   qreal newFontPointSize = currentFontPointSize * 0.8;
   qreal fontPointSizeChange = currentFontPointSize - newFontPointSize;
textArea->zoomOut(fontPointSizeChange);

qreal currentFontPointSize = textArea->font().pointSize();
   qreal newFontPointSize = currentFontPointSize * 0.8;
   qreal fontPointSizeChange = currentFontPointSize - newFontPointSize;
textArea->zoomOut(fontPointSizeChange);

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for zooming out and

qreal currentFontPointSize = textArea->font().pointSize();
   qreal newFontPointSize = currentFontPointSize * 1.25;
   qreal fontPointSizeChange = newFontPointSize - currentFontPointSize;
textArea->zoomIn(fontPointSizeChange);

qreal currentFontPointSize = textArea->font().pointSize();
   qreal newFontPointSize = currentFontPointSize * 1.25;
   qreal fontPointSizeChange = newFontPointSize - currentFontPointSize;
textArea->zoomIn(fontPointSizeChange);

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for zooming in and that works!

Only problem I now have is that the fonts of the QtextDocument are also changing and I want to keep that the same, because I'm making a pdf of the QTextDocument.
When I zoomOut the QTextEdit I get very small fonts in the pdf and I want to keep the same proportions. That's why I thought of changing the size of the QTextDocument as well.
I tried:

QSizeF currentDocumentSize = textArea->document()->size();
textArea->document()->setPageSize(0.8 * currentDocumentSize);

QSizeF currentDocumentSize = textArea->document()->size();
textArea->document()->setPageSize(0.8 * currentDocumentSize);

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and

textArea->document()->setPageSize(textArea->size());

textArea->document()->setPageSize(textArea->size());

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both don't give the good size, they make the QTextEdit a tiny bit to large.

Do you have any idea how I can resize the QTextEdit while keeping the QTextDocument the same size for pdf and printing?
Or am I trying to do things with a QTextWidget that are not possible and should I use an own Widget?