//顯示整數 QSpinBox *spin = new QSpinBox(this); spin->setMinimum(10); spin->setMaximum(300); spin->setPrefix("$ "); spin->setValue(200); //設置默認值,必須在10-300之間,不然離10進就是10,離300進就是300 spin->setGeometry(10, 30, 100, 30); QDoubleSpinBox * doublespin = new QDoubleSpinBox(this); doublespin->setMinimum(10.0); doublespin->setMaximum(300.0); doublespin->setValue(50.5); doublespin->setSuffix(" mm"); doublespin->setGeometry(30 + 110, 30, 100, 30); //經常使用的信號:valueChanged(int),valueChanged(double)