将焦点放在 QlineEdit 小部件上

问题描述

我正在尝试组合一个简单的小部件，其中焦点自动放在 QLineEdit 小部件上(它用于条形码扫描仪输入，我不希望最终用户必须单击小部件).

I am trying to put together a simple widget where the focus is automatically put to a QLineEdit widget (It is for a barcode scanner input, and I don't want the end users to have to click in the widget).

相关代码如下:

from qtmodern import styles, windows
from qtpy import QtGui, QtCore
from qtpy.QtWidgets import *
from qtpy.QtCore import Qt

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

        layout = QVBoxLayout()

        self.lineEdit = QLineEdit(self)
        self.lineEdit.setPlaceholderText('foobar')  
        self.lineEdit.setFocusPolicy(Qt.StrongFocus)      
        self.lineEdit.setFocus()

        layout.addWidget(self.lineEdit)

        self.setLayout(layout)
        self.show()

def main():
    app = QApplication([])
    styles.dark(app)

    g = windows.ModernWindow(MyGui())
    g.resize(350,100)
    location = (50, 100)
    g.move(location[0], location[1])
    g.setWindowTitle('SmallTest')

    g.show()
    app.exec_()

if __name__ == '__main__':
   main()

它不想将焦点放在 lineEdit 小部件上.我猜这是我错过的非常明显的东西，但我已经挖了一段时间试图找到它，但还没有偶然发现它.

And it doesn't want to put the focus on the lineEdit widget. I'm guessing its something really obvious that I've missed, but I've been digging around for a while trying to find it, and haven't stumbled upon it yet.

推荐答案

你必须使用 setFocus() 小部件显示后.

You must use setFocus() after the widget is displayed.

from qtmodern import styles, windows
from qtpy import QtGui, QtCore
from qtpy.QtWidgets import *
from qtpy.QtCore import Qt

class MyGui(QWidget):
    def __init__(self, parent=None):
        super(MyGui, self).__init__(parent)
        layout = QVBoxLayout(self)
        self.lineEdit = QLineEdit(self)
        self.lineEdit.setPlaceholderText('foobar')  
        self.lineEdit.setFocusPolicy(Qt.StrongFocus)
        layout.addWidget(self.lineEdit)

def main():
    app = QApplication([])
    styles.dark(app)
    gui = MyGui()
    g = windows.ModernWindow(gui)
    g.resize(350,100)
    location = (50, 100)
    g.move(*location)
    g.setWindowTitle('SmallTest')
    g.show()
    gui.lineEdit.setFocus()
    app.exec_()

if __name__ == '__main__':
   main()