Establecer Ancho QpushButton

//Use this:

QPushButton* const button = new QPushButton(QString("<"), this); 
const QSize BUTTON_SIZE = QSize(22, 22);
button->setMinimumSize(BUTTON_SIZE);

//or:

button->setSize(BUTTON_SIZE);

//or:

button->setMinimumSize(BUTTON_SIZE);

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