QFont Object not recognized.

[FelixB]

QFont font("Times",12);
myWidget.setFont(font);

QFont font("Times",12);
myWidget.setFont(font);

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[eLancaster]

I still dont understand why you have to do that. I've never read of anything like that, i'm very sorry to say :$
also i still get the error "invalid use of void expression"

[stampede]

also i still get the error "invalid use of void expression"

Because code like this

ui->SLineEdit->setFont(font->setBold(false));

ui->SLineEdit->setFont(font->setBold(false));

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makes no sense: font->setBold() is a method that returns 'void', and "setFont()" requires 'const QFont&'.
Modify your font and then assign it to QLineEdits:

font->setBold(true);
font->...
ui->lineEdit->setFont( *font ); //!< if you dont know why its here ...

font->setBold(true);
font->...
ui->lineEdit->setFont( *font ); //!< if you dont know why its here ...

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