Question

我是Python和Qt Designer的新手。使用给定的代码，我希望用户在QLineEdit小部件中输入文本，按下复制！按钮，看到输入的文字取代了“N / A”。标签。我的问题是：按照这个步骤，如何通过简单的鼠标点击清除QLineEdit小部件中输入的文本？

根据我的阅读（this，this和this），我似乎需要在扩展QLineEdit的新类中重新实现focusInEvent（）。我的问题是我的GUI代码是使用pyuic5从Qt Designer导入的，上面引用的例子似乎并没有考虑到这一点。

这是我的代码：

from PyQt5.QtWidgets import *
import sys

import QLineEdit_test


class MainWindow(QMainWindow, QLineEdit_test.Ui_QLineEdit_test):

    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.setupUi(self)

        self.copy_button.clicked.connect(self.copy_and_print)

    def copy_and_print(self):

        self.label.setText(self.lineEdit.text())


def main():

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

if __name__ == "__main__":
    main()

这是我转换的.ui文件：

from PyQt5 import QtCore, QtGui, QtWidgets

class Ui_QLineEdit_test(object):
    def setupUi(self, QLineEdit_test):
        QLineEdit_test.setObjectName("QLineEdit_test")
        QLineEdit_test.resize(300, 200)
        QLineEdit_test.setMaximumSize(QtCore.QSize(300, 200))
        self.centralwidget = QtWidgets.QWidget(QLineEdit_test)
        self.centralwidget.setObjectName("centralwidget")
        self.gridLayout_2 = QtWidgets.QGridLayout(self.centralwidget)
        self.gridLayout_2.setObjectName("gridLayout_2")
        self.gridLayout = QtWidgets.QGridLayout()
        self.gridLayout.setObjectName("gridLayout")
        self.lineEdit = QtWidgets.QLineEdit(self.centralwidget)
        self.lineEdit.setMaximumSize(QtCore.QSize(120, 16777215))
        self.lineEdit.setObjectName("lineEdit")
        self.gridLayout.addWidget(self.lineEdit, 0, 0, 1, 1)
        self.copy_button = QtWidgets.QPushButton(self.centralwidget)
        self.copy_button.setObjectName("copy_button")
        self.gridLayout.addWidget(self.copy_button, 1, 0, 1, 1)
        self.label = QtWidgets.QLabel(self.centralwidget)
        self.label.setMaximumSize(QtCore.QSize(200, 20))
        self.label.setAlignment(QtCore.Qt.AlignCenter)
        self.label.setObjectName("label")
        self.gridLayout.addWidget(self.label, 2, 0, 1, 1)
        self.gridLayout_2.addLayout(self.gridLayout, 0, 0, 1, 1)
        QLineEdit_test.setCentralWidget(self.centralwidget)
        self.menubar = QtWidgets.QMenuBar(QLineEdit_test)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 300, 22))
        self.menubar.setObjectName("menubar")
        QLineEdit_test.setMenuBar(self.menubar)
        self.statusbar = QtWidgets.QStatusBar(QLineEdit_test)
        self.statusbar.setObjectName("statusbar")
        QLineEdit_test.setStatusBar(self.statusbar)

        self.retranslateUi(QLineEdit_test)
        QtCore.QMetaObject.connectSlotsByName(QLineEdit_test)

    def retranslateUi(self, QLineEdit_test):
        _translate = QtCore.QCoreApplication.translate
        QLineEdit_test.setWindowTitle(_translate("QLineEdit_test", "MainWindow"))
        self.copy_button.setText(_translate("QLineEdit_test", "Copy!"))
        self.copy_button.setShortcut(_translate("QLineEdit_test", "Return"))
        self.label.setText(_translate("QLineEdit_test", "N/A"))

谢谢！

Answer 1

解决方案是促使QtDesigner使用我们的自定义QLineEdit，我们在mousePressEvent的帮助下实现点击的信号，此类将被称为ClickableLineEdit，该文件将被称为ClickableLineEdit.py。

<强> ClickableLineEdit.py

from PyQt5.QtCore import pyqtSignal
from PyQt5.QtWidgets import QLineEdit


class ClickableLineEdit(QLineEdit):
    clicked = pyqtSignal()
    def mousePressEvent(self, event):
        self.clicked.emit()
        QLineEdit.mousePressEvent(self, event)

为了推广它，将考虑以下结构：

.
├── ClickableLineEdit.py
├── main.py  
├── your.ui
└── QLineEdit_test.py

使用Qt Designer打开设计并右键单击QLineEdit并选择Promote to ...：

将打开一个菜单并放置以下内容

然后按下并推广。然后我们再次生成代码。

然后我们将信号连接到clear：

class MainWindow(QMainWindow, QLineEdit_test.Ui_QLineEdit_test):

    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.setupUi(self)

        self.copy_button.clicked.connect(self.copy_and_print)
        self.lineEdit.clicked.connect(self.lineEdit.clear)

    def copy_and_print(self):
        self.label.setText(self.lineEdit.text())

更新

<强> PySide2：

from PySide2 import QtCore, QtWidgets


class ClickableLineEdit(QtWidgets.QLineEdit):
    clicked = QtCore.Signal()

    def mousePressEvent(self, event):
        super(ClickableLineEdit, self).mousePressEvent(event)
        self.clicked.emit()


class App(QtWidgets.QWidget):
    def __init__(self):
        super().__init__()

        self.lineedit = ClickableLineEdit()
        self.lineedit.clicked.connect(self.lineedit.clear)

        lay = QtWidgets.QVBoxLayout(self)
        lay.addWidget(self.lineedit)


if __name__ == "__main__":
    import sys

    app = QtWidgets.QApplication.instance()
    if app is None:
        app = QtWidgets.QApplication(sys.argv)
    ex = App()
    ex.show()
    sys.exit(app.exec_())

Answer 2

def __init__(self, *args, **kwargs):
    QWidget.__init__(self, *args, **kwargs)

    layout = QGridLayout()
    self.setLayout(layout)

    self.lineedit = QLineEdit()
    self.lineedit.returnPressed.connect(self.press)
    layout.addWidget(self.lineedit, 0, 0)

def press(self):
    print("Hi World")
    self.lineedit.clear()

Answer 3

我在一行中有一个可选的解决方案：

self.lineEdit.mouseReleaseEvent = self.copy_and_print

确保在函数中接收到两个参数（self，event）希望我能帮到你

完整文章：https://wiki.python.org/moin/PyQt/Making%20non-clickable%20widgets%20clickable

清除点击事件的QLineEdit

3 个答案: