How to change current line format in QTextEdit?

[FinderCheng]

Hi, there! I want to find out how to change current line format in QTextEdit?

In the document I read that formatting can be applied to the current text document using the setCharFormat(), mergeCharFormat(), setBlockFormat() and mergeBlockFormat() functions. If the cursor has no selection, current block format will be changed. But in my application, the current block in which cursor is couldn't be changed. May I missed something? Then how could I change current block format which has no selection?

Thank you all!

[wysota]

What have you tried so far?

[FinderCheng]

Here is what did:

QTextCursor cursor = this->textCursor();
QTextBlockFormat blockFmt;
blockFmt.setNonBreakableLines(true);
blockFmt.setPageBreakPolicy(QTextFormat::PageBreak_AlwaysBefore);
QTextCharFormat charFmt;
charFmt.setFont(data->visualFont());
if(!cursor.hasSelection()) {
    cursor.beginEditBlock();
    cursor.setBlockFormat(blockFmt);
    cursor.mergeBlockCharFormat(charFmt);
    QTextBlock block = cursor.block();
    block.setUserData(data);
    cursor.endEditBlock();
}

QTextCursor cursor = this->textCursor();
QTextBlockFormat blockFmt;
blockFmt.setNonBreakableLines(true);
blockFmt.setPageBreakPolicy(QTextFormat::PageBreak_AlwaysBefore);
QTextCharFormat charFmt;
charFmt.setFont(data->visualFont());
if(!cursor.hasSelection()) {
    cursor.beginEditBlock();
    cursor.setBlockFormat(blockFmt);
    cursor.mergeBlockCharFormat(charFmt);
    QTextBlock block = cursor.block();
    block.setUserData(data);
    cursor.endEditBlock();
}

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What I want to do is: change current line's format if there is no selection. So if cursor.hasSelection() is false, I just merge new format to block chars. But this does not work.

[wysota]

You have to set the cursor back on the text edit.

[FinderCheng]

I added this->setTextCorsor(cursor); after cursor.endEditBlock();, but it still doesn't work. In fact, after adding this, the whole block becomes invisible.

[wysota]

What is the ultimate result you want to receive? Do you wish to change the format of the whole block or what exactly?