from PyQt5.QtWidgets import QApplication, QWidget, QDoubleSpinBox, QVBoxLayout
app = QApplication([])
window = QWidget()
layout = QVBoxLayout()
# 創(chuàng)建控件并設(shè)置初始屬性
spinbox = QDoubleSpinBox()
spinbox.setRange(-100.0, 100.0)   # 設(shè)置數(shù)值范圍
spinbox.setSingleStep(0.5)        # 設(shè)置步長（箭頭點擊一次的變化量）
spinbox.setDecimals(2)            # 保留兩位小數(shù)
spinbox.setValue(3.14)            # 設(shè)置初始值
layout.addWidget(spinbox)
window.setLayout(layout)
window.show()
app.exec_()

def on_value_changed(value):
    print(f"當(dāng)前值: {value}")
spinbox.valueChanged.connect(on_value_changed)

# 當(dāng)數(shù)值超過50時，自動擴展范圍
def check_range(value):
    if value > 50.0:
        spinbox.setRange(0.0, 100.0)
    else:
        spinbox.setRange(0.0, 50.0)
spinbox.valueChanged.connect(check_range)

spinbox.setPrefix("溫度: ")     # 添加前綴
spinbox.setSuffix("°C")        # 添加后綴
# 使用自定義格式（如貨幣）
spinbox.setDecimals(0)
spinbox.setPrefix("$ ")

spinbox.setKeyboardTracking(False)  # 輸入完成后再驗證（而非實時）
def validate_input(value):
    if value < 0:
        return 0.0  # 自動修正為最小值
    return value
spinbox.valueFromText = lambda text: validate_input(float(text))

def dynamic_step(value):
    if value < 1.0:
        return 0.1
    elif value < 10.0:
        return 0.5
    else:
        return 1.0
spinbox.setSingleStep(0.1)  # 初始步長
def on_step_up():
    current = spinbox.value()
    step = dynamic_step(current)
    spinbox.setValue(current + step)
def on_step_down():
    current = spinbox.value()
    step = dynamic_step(current)
    spinbox.setValue(current - step)
# 替換默認(rèn)的上下箭頭行為
spinbox.stepUp.connect(on_step_up)
spinbox.stepDown.connect(on_step_down)