如何将焦点对一行编辑更改为另一行编辑

Question

这是我的示例程序，在此我有两行编辑，我想使用键盘设置文本。我在两行编辑中得到相同的文本，任何人都可以帮助我如何关注特定选定的内容行编辑。如果我选​​择了 cash_received 行编辑，我的文本将设置为该对象。提前谢谢你。 下面是我的代码：

import sys
from PyQt4 import QtGui,QtCore
from functools import partial

class Example(QtGui.QWidget):

    def __init__(self):
        super(Example, self).__init__()

        self.initUI()

    def initUI(self):
        self.Vbox = QtGui.QGridLayout()
        hbox = QtGui.QHBoxLayout(spacing = 0)
        hbox.setContentsMargins(0, 0, 0, 0)
        cash_btn = QtGui.QPushButton("cash")
        card_btn = QtGui.QPushButton("Card")
        cash_btn.clicked.connect(self.cash_card_payment)
        wallet_btn = QtGui.QPushButton("wallet")
        hbox.addWidget(cash_btn)
        hbox.addWidget(card_btn)
        hbox.addWidget(wallet_btn)
        self.Vbox.addLayout(hbox,0,0)

        grid = QtGui.QGridLayout()
        self.Vbox.addLayout(grid,3,0)
        self.setLayout(self.Vbox)

        names = [
                '7', '8', '9', '-',
                '4', '5', '6', '+',
                '1', '2', '3', 'enter',
                '0', '',  '.']

        positions = [(i,j) for i in range(4) for j in range(4)]

        for position, name in zip(positions, names):
            x, y = position

            if name == '':
                continue
            button = QtGui.QPushButton(name)
            button.setFocusPolicy(QtCore.Qt.NoFocus)
            button.clicked.connect(partial(self.buttonClicked,name))

            button.setMinimumWidth(50)
            button.setMinimumHeight(50)

            if button.text() == 'enter':
                button.setMinimumHeight(110)
                grid.addWidget(button, x, y, 2,1)
            elif button.text() == '0':
                grid.addWidget(button, x, y, 1,2)
            else:
                grid.addWidget(button, x, y, 1,1)


    def cash_card_payment(self):
        print "cardssss"
        cash_payment_vbox = QtGui.QVBoxLayout()
        cash_payment_vbox.setAlignment(QtCore.Qt.AlignCenter)
        self.cash_received = QtGui.QLineEdit()
        self.cash_tender = QtGui.QLineEdit()
        cash_payment_vbox.addWidget(self.cash_received)
        cash_payment_vbox.addWidget(self.cash_tender)
        self.Vbox.addWidget(self.cash_received,1,0)
        self.Vbox.addWidget(self.cash_tender,2,0)

    def buttonClicked(self,name):
        print name
        self.cash_received.setText(name)
        #herei want to set the text for
        # cash_received objec only
        self.cash_tender.setText(name) # here i want to set the text for
        # cash_tender objec only how can i focus the one line edit to another
if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    ex = Example()
    ex.show()
    ex.setWindowTitle('Calculator')
    ex.setGeometry(300, 150, 500,400)
    sys.exit(app.exec_())

Answer 1

直接在QLineEdit中设置文字是无敌的，说你使用QTextEdit或者其他widget之后，说你想实现clear key等，你的解决方案很大程度上取决于widget。

耦合度较低的解决方案是使用QCoreApplication::postEvent() 将QKeyEvent 发送到使用QApplication::focusWidget() 获得焦点的小部件

from PyQt4 import QtCore, QtGui

class KeyPad(QtGui.QWidget):
    def __init__(self, parent=None):
        super(KeyPad, self).__init__(parent)
        grid_lay = QtGui.QGridLayout(self)

        keys =  [
            ("7", QtCore.Qt.Key_7 , 0, 0, 1, 1),
            ("8", QtCore.Qt.Key_8 , 0, 1, 1, 1),
            ("9", QtCore.Qt.Key_9 , 0, 2, 1, 1),
            ("-", QtCore.Qt.Key_Minus , 0, 3, 1, 1),
            ("4", QtCore.Qt.Key_4 , 1, 0, 1, 1),
            ("5", QtCore.Qt.Key_5 , 1, 1, 1, 1),
            ("6", QtCore.Qt.Key_6 , 1, 2, 1, 1),
            ("+", QtCore.Qt.Key_Plus , 1, 3, 1, 1),
            ("1", QtCore.Qt.Key_1 , 2, 0, 1, 1),
            ("2", QtCore.Qt.Key_2 , 2, 1, 1, 1),
            ("3", QtCore.Qt.Key_3 , 2, 2, 1, 1),
            ("0", QtCore.Qt.Key_0 , 3, 0, 1, 2),
            (".", QtCore.Qt.Key_Period , 3, 2, 1, 1),
            ("enter", QtCore.Qt.Key_Return , 2, 3, 2, 1)
        ]

        for text, key, r, c, sr, sc in keys:
            button = QtGui.QPushButton(text=text, focusPolicy=QtCore.Qt.NoFocus)
            button.setProperty("_key_", key)
            grid_lay.addWidget(button, r, c, sr, sc)
            button.clicked.connect(self.on_clicked)
            if text == "enter":
                sp = button.sizePolicy()
                sp.setVerticalPolicy(sp.horizontalPolicy())
                button.setSizePolicy(sp)

    @QtCore.pyqtSlot()
    def on_clicked(self):
        button = self.sender()
        text = "" if button.text() == "enter" else button.text()
        key = button.property("_key_")
        widget = QtGui.QApplication.focusWidget()
        if hasattr(key, 'toPyObject'):
            key = key.toPyObject()
        if widget:
            event = QtGui.QKeyEvent(QtCore.QEvent.KeyPress, key, QtCore.Qt.NoModifier, text)
            QtCore.QCoreApplication.postEvent(widget, event)

class Widget(QtGui.QWidget):
    def __init__(self, parent=None):
        super(Widget, self).__init__(parent)

        cash_btn = QtGui.QPushButton("cash", clicked=self.on_cash_btn_clicked)
        card_btn = QtGui.QPushButton("Card")
        wallet_btn = QtGui.QPushButton("wallet")

        self.cash_widget = QtGui.QWidget(visible=False)
        self.cash_received = QtGui.QLineEdit()
        self.cash_tender = QtGui.QLineEdit()
        cash_lay = QtGui.QVBoxLayout(self.cash_widget)
        cash_lay.addWidget(self.cash_received)
        cash_lay.addWidget(self.cash_tender)

        keypad = KeyPad()

        hbox = QtGui.QHBoxLayout()
        hbox.addWidget(cash_btn)
        hbox.addWidget(card_btn)
        hbox.addWidget(wallet_btn)

        vlay = QtGui.QVBoxLayout(self)
        vlay.addLayout(hbox)
        vlay.addWidget(self.cash_widget)
        vlay.addWidget(keypad)

    @QtCore.pyqtSlot()
    def on_cash_btn_clicked(self):
        self.cash_widget.setVisible(not self.cash_widget.isVisible())
        if self.cash_widget.isVisible():
            self.cash_received.setFocus()

if __name__ == '__main__':
    import sys
    app = QtGui.QApplication(sys.argv)
    w = Widget()
    w.show()
    sys.exit(app.exec_())

PyQt5 版本：

from PyQt5 import QtCore, QtGui, QtWidgets


class KeyPad(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(KeyPad, self).__init__(parent)
        grid_lay = QtWidgets.QGridLayout(self)

        keys = [
            ("7", QtCore.Qt.Key_7, 0, 0, 1, 1),
            ("8", QtCore.Qt.Key_8, 0, 1, 1, 1),
            ("9", QtCore.Qt.Key_9, 0, 2, 1, 1),
            ("-", QtCore.Qt.Key_Minus, 0, 3, 1, 1),
            ("4", QtCore.Qt.Key_4, 1, 0, 1, 1),
            ("5", QtCore.Qt.Key_5, 1, 1, 1, 1),
            ("6", QtCore.Qt.Key_6, 1, 2, 1, 1),
            ("+", QtCore.Qt.Key_Plus, 1, 3, 1, 1),
            ("1", QtCore.Qt.Key_1, 2, 0, 1, 1),
            ("2", QtCore.Qt.Key_2, 2, 1, 1, 1),
            ("3", QtCore.Qt.Key_3, 2, 2, 1, 1),
            ("0", QtCore.Qt.Key_0, 3, 0, 1, 2),
            (".", QtCore.Qt.Key_Period, 3, 2, 1, 1),
            ("enter", QtCore.Qt.Key_Return, 2, 3, 2, 1),
        ]

        for text, key, r, c, sr, sc in keys:
            button = QtWidgets.QPushButton(text=text, focusPolicy=QtCore.Qt.NoFocus)
            button.setProperty("_key_", key)
            grid_lay.addWidget(button, r, c, sr, sc)
            button.clicked.connect(self.on_clicked)
            if text == "enter":
                sp = button.sizePolicy()
                sp.setVerticalPolicy(sp.horizontalPolicy())
                button.setSizePolicy(sp)

    @QtCore.pyqtSlot()
    def on_clicked(self):
        button = self.sender()
        text = "" if button.text() == "enter" else button.text()
        key = button.property("_key_")
        widget = QtWidgets.QApplication.focusWidget()
        if hasattr(key, "toPyObject"):
            key = key.toPyObject()
        if widget:
            event = QtGui.QKeyEvent(
                QtCore.QEvent.KeyPress, key, QtCore.Qt.NoModifier, text
            )
            QtCore.QCoreApplication.postEvent(widget, event)


class Widget(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(Widget, self).__init__(parent)

        cash_btn = QtWidgets.QPushButton("cash", clicked=self.on_cash_btn_clicked)
        card_btn = QtWidgets.QPushButton("Card")
        wallet_btn = QtWidgets.QPushButton("wallet")

        self.cash_widget = QtWidgets.QWidget(visible=False)
        self.cash_received = QtWidgets.QLineEdit()
        self.cash_tender = QtWidgets.QLineEdit()
        cash_lay = QtWidgets.QVBoxLayout(self.cash_widget)
        cash_lay.addWidget(self.cash_received)
        cash_lay.addWidget(self.cash_tender)

        keypad = KeyPad()

        hbox = QtWidgets.QHBoxLayout()
        hbox.addWidget(cash_btn)
        hbox.addWidget(card_btn)
        hbox.addWidget(wallet_btn)

        vlay = QtWidgets.QVBoxLayout(self)
        vlay.addLayout(hbox)
        vlay.addWidget(self.cash_widget)
        vlay.addWidget(keypad)

    @QtCore.pyqtSlot()
    def on_cash_btn_clicked(self):
        self.cash_widget.setVisible(not self.cash_widget.isVisible())
        if self.cash_widget.isVisible():
            self.cash_received.setFocus()


if __name__ == "__main__":
    import sys

    app = QtWidgets.QApplication(sys.argv)
    w = Widget()
    w.show()
    sys.exit(app.exec_())