How to retain Syntax Highlighting during text highlight

Question

In most code editors, the text highlight does not remove the syntax colors.

For example:

• Visual Studio

• Sublime Text

I would like to simulate this function in the code editor I'm making in QT; however, the text highlight turns all of the text into a single color:

vs

Would it be possible to retain the syntax highlighting during a text highlight?

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FYI: I'm using a QPlainTextEdit and QSyntaxHighlighter to create the editor. I've tried changing the palette of the QPlainTextEdit, but I cannot seem to find a way to disable the HighlightedText effect.

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EDIT: Here is a simplified version of the code I'm using to add some context:

void MyHighlighter::highlightBlock(const QString& text) {
  // Sets characters 0 ~ 10 to be colored rgb(100, 200, 100)
  QTextCharFormat temp;
  temp.setForeground(QColor(100, 200, 100));
  setFormat(0, 10, temp);
}

Puckett

show more code, how do you define style. I'm sure you can define different style of text when it is selected and you simply missed that. – Abrahamabrahams

@MarekR I'm simply using the setFormat function within an extended QSyntaxHighlighter::highlightBlock. I've added a small example to the original post. I've tried looking for something to modify the QTextCharFormat to make the highlight color the same, but no luck. (Also, thanks for the post edit. Was unaware you could embed images like that >.<) – Puckett

I've checked how Qt Creator works. Sadly it has this issue, that selected text is in not colored. So it might be hard to do what you want. – Abrahamabrahams

@MarekR Ack, I see. Is there a specific place in the code I should look to find where the text re-color is done? Perhaps I could figure it out from there. – Puckett

Answer 1

Good news! After revisiting this issue, I found the solution after playing around for a bit. Feel a little stupid not trying this sooner as it works perfectly.

On the QPlainTextEdit (or whichever widget applicable to the scenario), you simply need to set the QPalette::HighlightedText to QBrush(Qt::NoBrush).

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For example, to replicate the transparent highlight from Sublime Text, you would simply do:

auto palette = textEditWidget->palette();

// provide highlight color with low alpha
palette.setBrush(QPalette::Highlight, QColor(255, 255, 255, 30));

// set highlight text brush to "No Brush"
palette.setBrush(QPalette::HighlightedText, QBrush(Qt::NoBrush));

// apply to widget
textEditWidget->setPalette(palette);

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Result:

Puckett