QPlainTextEdit, Read Only

[metdos]

This is the related code part:

while(..){
...
ui.dataTextEdit->insertPlainText(currentTime);
...
}

while(..){
...
ui.dataTextEdit->insertPlainText(currentTime);
...
}

To copy to clipboard, switch view to plain text mode 

dataTextEdit is an instance of QPlainTextEdit
and I put the line

ui.dataTextEdit->setReadOnly(TRUE);

ui.dataTextEdit->setReadOnly(TRUE);

To copy to clipboard, switch view to plain text mode 

and while program executes if I highlight some part of lines in plainTextEdit, these lines are vanishing.

if

I put the line

ui.dataTextEdit->setTextInteractionFlags(Qt::NoTextInteraction);

ui.dataTextEdit->setTextInteractionFlags(Qt::NoTextInteraction);

To copy to clipboard, switch view to plain text mode 

then there is no problem, but I can't copy paste this time.

What is problem with read-only, I want to be enable of copy-paste but not to change text.

Thanks.