Python——GUI编程 利息计算器 作业9（python programming）

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *

class calMoney(QDialog):
    def __init__(self,parent=None):
        super().__init__(parent)

        self.setWindowTitle('帅帅的利息计算器')

        # 定义QLable时，在快捷键字母前加“&”符号；
        # alt+P
        PrincipalLabel = QLabel("&Principal:")
        self.inpMoney = QDoubleSpinBox()
        self.inpMoney.setPrefix("$ ") # 设置前缀
        self.inpMoney.setRange(0.01,100000000)
        self.inpMoney.setValue(1000)
        PrincipalLabel.setBuddy(self.inpMoney)

        RateLabel = QLabel("&Rate:")
        self.inpRate = QDoubleSpinBox()
        self.inpRate.setSuffix(" %") # 设置后缀
        self.inpRate.setValue(5)
        RateLabel.setBuddy(self.inpRate)

        YearsLabel = QLabel("&Years:")
        self.inpYears = QComboBox()
        ls=[]
        for i in range(1,11):
            if i==1:
                year = str(i) + " year"
            else:
                year = str(i) + " years"
            ls.append(year)
        self.inpYears.addItems(ls)
        YearsLabel.setBuddy(self.inpYears)

        AmountLabel = QLabel("&Amount")
        self.oupAmount = QLabel("$ 1102.50")
        AmountLabel.setBuddy(self.oupAmount)   

        # 网格布局
        layout = QGridLayout()
        layout.addWidget(PrincipalLabel, 0, 0)
        layout.addWidget(self.inpMoney, 0, 1)
        layout.addWidget(RateLabel, 1, 0)
        layout.addWidget(self.inpRate, 1, 1)
        layout.addWidget(YearsLabel, 2, 0)
        layout.addWidget(self.inpYears, 2, 1)
        layout.addWidget(AmountLabel, 3, 0)
        layout.addWidget(self.oupAmount, 3, 1)

        # 信号与槽相连
        self.inpMoney.valueChanged.connect(self.updateAmount)
        self.inpRate.valueChanged.connect(self.updateAmount)
        self.inpYears.currentIndexChanged.connect(self.updateAmount)

        self.setLayout(layout)

    def updateAmount(self):
        principal = float(self.inpMoney.value())
        rate = float(self.inpRate.value())
        years = int(self.inpYears.currentIndex())
        amount = principal * pow((1 + 0.01 * rate),(years+1))
        self.oupAmount.setText("{0:.2f}".format(amount))
        pass

app = QApplication(sys.argv)
form = calMoney()
form.show()
app.exec_()