Figuring out the minimum size of rich text

Absurd

I have a QTextEdit which I initialize as follows:

QTextEdit* textEdit = new QTextEdit();
textEdit->setReadOnly(true);
textEdit->setHtml("<p style=\"color:red; font-family:'Courier New';\">Raw Header</p>");
textEdit->setAlignment(Qt::AlignCenter);
textEdit->append("<p style=\"font-family:'Courier New'\">00000000<br />00000000<br />00000000<br />00000000</p>");
textEdit->setAlignment(Qt::AlignCenter);

This textEdit is later added to a QGridLayout, and on that layout it looks like this:

I want to resize it to its minimum size without having scroll bars, something like:

textEdit->setFixedSize(minimumWidthWhileTextStillVisible, minimumHeightWhileTextStillVisible);

I tried to look around but I couldn't find a solution.
Every suggested solution I could find made the assumption that the QTextEdit is already visible which is not the case here.
I want to predetermine the width/height before the show() is called by the layout on that object.

Christian Ehrlicher

Good question. Maybe QTextDocument::size() returns it. Did not check it though.

Absurd

I tried that, unfortunately textEdit->document()->size() returns (0,0), probably because the document is not visible yet...

Will it help if I will subclass QTextEdit and re-implement the sizeHint()? Will the layout manager invoke the sizeHint() after the object is visible?

Christian Ehrlicher

@Absurd said in Figuring out the minimum size of rich text:

Will it help if I will subclass QTextEdit and re-implement the sizeHint()?

How do you know the size then?

Absurd

@Christian-Ehrlicher by returning QTextDocument::size() from sizeHint().
If the QTextEdit is visible by the time sizeHint() is invoked by the layout manager maybe it'll return the actual document size?

Christian Ehrlicher

Maybe first try out if the expected value of QTextDocument::size() is correct when the widget is visible. Then it's maybe worth a try.

Absurd

@Christian-Ehrlicher thanks.
Yes, since posting that I tried that too, and that does not worth a try.
The QTextDocument::size() returns QSize(72, 173), so when I try to use that as the QTextEdit size I get:

I was thinking iterating over the QTextBlock's in the QTextDocument and trying to figure out the expected size from QTextBlock::blockFormat() somehow, but again - if it's not visible everything returns 0 (for example QTextBlockFormat::lineHeight() returns 0 for the two blocks).

Is there a way to somehow render it internally into an object without actually show()'ing it?

Christian Ehrlicher

There is also a function QTextDocument::idealWidth() - what does it return?

Absurd

This one returns 8 (far from being ideal).

JonB

@Absurd Looks like it thinks a very narrow document would be a good idea ;-)