如何在QLineEdit中插入一个按钮

Question

我需要帮助在QLineEdit中插入一个可以调用函数的按钮。例如，像谷歌图片中展示的那样：

- Andrew Zhuk

Answer 1

以下是从此处获取的Qt代码的近乎直接翻译。

区别：

• 按钮总是可见的
• 点击该按钮会发出buttonClicked(bool)信号

代码：

from PyQt4 import QtGui, QtCore

class ButtonLineEdit(QtGui.QLineEdit):
    buttonClicked = QtCore.pyqtSignal(bool)

    def __init__(self, icon_file, parent=None):
        super(ButtonLineEdit, self).__init__(parent)

        self.button = QtGui.QToolButton(self)
        self.button.setIcon(QtGui.QIcon(icon_file))
        self.button.setStyleSheet('border: 0px; padding: 0px;')
        self.button.setCursor(QtCore.Qt.ArrowCursor)
        self.button.clicked.connect(self.buttonClicked.emit)

        frameWidth = self.style().pixelMetric(QtGui.QStyle.PM_DefaultFrameWidth)
        buttonSize = self.button.sizeHint()

        self.setStyleSheet('QLineEdit {padding-right: %dpx; }' % (buttonSize.width() + frameWidth + 1))
        self.setMinimumSize(max(self.minimumSizeHint().width(), buttonSize.width() + frameWidth*2 + 2),
                            max(self.minimumSizeHint().height(), buttonSize.height() + frameWidth*2 + 2))

    def resizeEvent(self, event):
        buttonSize = self.button.sizeHint()
        frameWidth = self.style().pixelMetric(QtGui.QStyle.PM_DefaultFrameWidth)
        self.button.move(self.rect().right() - frameWidth - buttonSize.width(),
                         (self.rect().bottom() - buttonSize.height() + 1)/2)
        super(ButtonLineEdit, self).resizeEvent(event)

用法：

import sys
from PyQt4 import QtGui

def buttonClicked():
    print 'You clicked the button!'

if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)

    main = ButtonLineEdit('/path/to/my_fancy_icon.png')
    main.buttonClicked.connect(buttonClicked)
    main.show()

    sys.exit(app.exec_())

- Avaris

---

从Qt 5.2版本开始，它提供了QLineEdit.addAction()方法，这是一种内置的方法来实现这个功能。同时，QLineEdit.setClearButtonEnabled()方法可以在右侧添加一个交叉按钮（类似于某些OSX控件），用于清除小部件的内容。 - blameless75

@Avaris，我已经根据我的需求调整了您的解决方案，但是存在一个小问题。当QLineEdit的内容过长时，它会与按钮重叠。我通过将按钮的背景颜色设置为白色来在一定程度上缓解了这个问题。然而，这种方法的问题是部分内容会消失在按钮后面。无法使用光标或鼠标向右滚动以显示其余内容。我该如何解决这个问题？谢谢。 - Giuseppe

Answer 2

以下是可运行的代码：

from PyQt4.QtGui import *
from PyQt4.QtCore import *
from sys import argv, exit

class ButtonInLineEdit(QLineEdit):
    def __init__(self,parent=None):
        QLineEdit.__init__(self,parent)

        self.ButtonShowKeyboard = QToolButton(self)
        self.ButtonShowKeyboard.setCursor(Qt.PointingHandCursor)

        self.ButtonShowKeyboard.setFocusPolicy(Qt.NoFocus)
        self.ButtonShowKeyboard.setIcon(QIcon("icons/myIcon.png"))
        self.ButtonShowKeyboard.setStyleSheet("background: transparent; border: none;")

        layout = QHBoxLayout(self)
        layout.addWidget(self.ButtonShowKeyboard,0,Qt.AlignRight)

        layout.setSpacing(0)
        layout.setMargin(5)

        self.ButtonShowKeyboard.setToolTip(QApplication.translate("None", "Show virtual keyboard", None, QApplication.UnicodeUTF8))

def MyFunction(arg=None):
    print "MyFunction() called: arg = %s"%arg

a=QApplication(argv)
LineEdit = ButtonInLineEdit()
LineEdit.connect(LineEdit.ButtonShowKeyboard, SIGNAL("clicked()"), MyFunction)
LineEdit.show()
exit(a.exec_())

- alphanumeric

---

嘿，我正在做类似的事情，但是我正在尝试将这样的“按钮”附加到我在Qt Designer中创建的用户界面上。想知道是否可以使用您的解决方案来实现？ - yan

Answer 3

从Qt 5.2开始，有一个内置的方法QLineEdit.addAction()可以实现此功能。另外，QLineEdit.setClearButtonEnabled()将在右侧添加一个交叉按钮（类似于某些OSX控件），以清除小部件的内容。

- blameless75

---

你能举个例子吗？ - Mattwmaster58

addAction 中的图标对我来说不可见。 - eri0o

Answer 4

在qt C++中，我可以将pushButton拖放到LineEdit的左侧。之后，我只需要使用以下代码为LineEdit设置styleSheet：

int FramWidth = lineEdit->style()->pixelMetric(QStyle::PM_DefaultFrameWidth);

lineEdit->setStyleSheet(QString("QLineEdit{padding-right: %1px; }").arg(ui->pushButton->sizeHint().width() + FramWidth +5));

对我来说它有效。希望能帮到你。

- taiNguyen

Answer 5

感谢我们的同事Avaris，但他的例子并没有让我信服，所以我决定做一个更简单、代码更少的例子。去学习吧！

#this code for example in btninlineedit.py

from PyQt4.QtGui import *
from PyQt4.QtCore import Qt
from PyQt4 import QtCore, QtGui
#Andrey Zhuk.
#####
try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    _fromUtf8 = lambda s: s

class ButtonInLineEdit(QLineEdit):
    def __init__(self,parent=None):
        QLineEdit.__init__(self,parent)

        self.ButtonShowKeyboard = QToolButton(self)
        self.ButtonShowKeyboard.setCursor(Qt.PointingHandCursor)
        #self.ButtonShowKeyboard.show()
        self.ButtonShowKeyboard.setFocusPolicy(Qt.NoFocus)
        self.ButtonShowKeyboard.setIcon(QtGui.QIcon("images/YourIcon.svg"))
        self.ButtonShowKeyboard.setStyleSheet("background: transparent; border: none;")

        layout = QHBoxLayout(self)
        layout.addWidget(self.ButtonShowKeyboard,0,Qt.AlignRight)

        layout.setSpacing(0)
        layout.setMargin(5)
        # ToolTip 
        self.ButtonShowKeyboard.setToolTip(QtGui.QApplication.translate("None", "Show virtual keyboard", None, QtGui.QApplication.UnicodeUTF8))


#this code for example in main.py            
class main(/////****///**/): 
    def __init__(self):
     #blablablablaaaa

        self.KeyboardShow = False

self.connect(self.LineEdit.ButtonShowKeyboard, QtCore.SIGNAL("clicked()"), self.KeyboardShowHide)


def KeyboardShowHide(self):
    try:
        if self.KeyboardShow:
            self.KeyboardShow = False
            self.WidgetKeyboard.hide()
        else:
            self.KeyboardShow = True
            self.WidgetKeyboard.show()
    except:
            debug ("ошибка при вызове функции скрытые или показа клавиатуры (Main Window)")
#this code for example in btninlineedit.py

from forms.btninlineedit import ButtonInLineEdit



        self.LineEdit = ButtonInLineEdit()

- Andrew Zhuk

Answer 6

class LineEditFileDialogWidget(QtWidgets.QLineEdit):
    def __init__(self, parent=None):
        super(LineEditFileDialogWidget, self).__init__(parent)
        self.setReadOnly(True)

        icon = QtWidgets.QApplication.style().standardIcon(QtWidgets.QStyle.SP_DirIcon)
        self.action = self.addAction(icon, QtWidgets.QLineEdit.TrailingPosition)
        self.action.triggered.connect(some function)

这是一个使用图标和QLineEdit的示例

- user12809213