Question

我正在使用PyQt 4编写一个单位转换器。这里，我遇到了一个问题。

class UnitConverter(QtGui.QComboBox):
    def __init__(self, parent=None):
        super(UnitConverter, self).__init__(parent)
        self.unitsdict = {
            "mass": {"g": 1, "kg": 1000, "t": 1000000, "oz": 28.3495231, "lb": 453.59237},
            "pressure": {"pa": 1, "kpa": 1000, "mpa": 1000000, "bar": 100000, "atm": 101325,
                        "tor": 133.3223684, "psi": 6894.757, "at": 98066.5}
        }

    def combo(self, measurement):
        for key in self.unitsdict[measurement]:
            self.addItem(self.tr(key), self.unitsdict[measurement][key])

    def comboConnect(self, table, row, column):
        self.names = locals()
        #tablevar = "self.table_" + str(row) + "_" + str(column)
        self.rowvar = "self.row_" + str(row) + "_" + str(column)
        self.columnvar = "self.column_" + str(row) + "_" + str(column)
        self.names[self.rowvar] = row
        self.names[self.columnvar] = column
        self.table = table
        self.base = self.itemData(self.currentIndex())
        self.currentIndexChanged.connect(self.change)

    def change(self):
        tobase = self.itemData(self.currentIndex())
        try:
            self.value = float(self.table.item(self.names[self.rowvar], self.names[self.columnvar]).text())
            tovalue = '%f' % (self.value * self.base / tobase)
            changeitem = QtGui.QTableWidgetItem(str(tovalue))
            self.table.setItem(self.names[self.rowvar], self.names[self.columnvar], changeitem)
        except:
            pass
        self.base = tobase

我希望它可以在我更改组合框的索引时自动计算结果。

当只有一个QTableWidgetItem连接到它时，它可以工作。

table = QTableWidget(10, 3)
combo = Unit converter()
combo.combo("pressure")
table.setCellWidget(5, 0, combo)
combo.comboConnect(table, 5, 1)

但是当我连接另一个QTableWidgetItem时，第一个意外地不再起作用。

table = QTableWidget(10, 3)
combo = Unit converter()
combo.combo("pressure")
table.setCellWidget(5, 0, combo)
combo.comboConnect(table, 5, 1)
combo.comboConnect(table, 5, 2)

所以，我想知道问题是什么。或者，我该如何使表（5,1）再次工作？

Answer 1

主要问题是你要覆盖很多变量，所以你只看到最后保存的数据，例如self.rowvar和self.columnvar保存最后一行和列，而不是更新你必须将它添加到列表或其他东西类似。

class UnitConverter(QtGui.QComboBox):
    def __init__(self, table, parent=None):
        super(UnitConverter, self).__init__(parent)
        self.unitsdict = {
            "mass": {"g": 1, "kg": 1000, "t": 1000000, "oz": 28.3495231, "lb": 453.59237},
            "pressure": {"pa": 1, "kpa": 1000, "mpa": 1000000, "bar": 100000, "atm": 101325,
                         "tor": 133.3223684, "psi": 6894.757, "at": 98066.5}
        }
        self.table = table
        self.base = -1
        self.items = []
        self.currentIndexChanged.connect(self.change)

    def combo(self, measurement):
        for key in self.unitsdict[measurement]:
            self.addItem(self.tr(key), self.unitsdict[measurement][key])
        self.base = self.itemData(self.currentIndex())

    def comboConnect(self, row, column):
        self.items.append((row, column))

    def change(self, ix,):
        tobase = self.itemData(ix)
        factor = self.base / tobase
        self.base = tobase

        for r, c in self.items:
            it = self.table.item(r, c)
            try:
                value = float(it.text())
                tovalue = '%f' % (value * factor)
                it.setText(tovalue)
            except:
                pass


if __name__ == '__main__':
    import sys

    app = QtGui.QApplication(sys.argv)
    table = QtGui.QTableWidget(10, 3)
    combo = UnitConverter(table)
    combo.combo("pressure")
    table.setCellWidget(5, 0, combo)
    combo.comboConnect(5, 1)
    combo.comboConnect(5, 2)
    table.show()
    sys.exit(app.exec_())

这个Python代码有什么问题？

1 个答案: