将小部件放置在QMainWindow中,如何放置而不是setCentralWidget

时间:2018-10-28 15:07:17

标签: python pyqt pyqt5

我正在使用QGridLayout,并且通过使用setCentralWidget函数,行和列(0,0)从窗口的中心开始,这留下了很多空白。

如何使其居中,但要从窗口顶部开始而不是在中间?

我对Qt来说还很陌生,想知道我是否处理错了?我应该改为为QWidget创建新类吗?

class App(QMainWindow):
    def __init__(self):
        super().__init__()
        self.title = 'Data visualizing'
        self.left = 50
        self.top = 50
        self.width = 300
        self.height = 100
        self.initUI()

    def initUI(self):
        self.central_widget = QWidget()
        self.setCentralWidget(self.central_widget)

        # Create textbox
        self.textbox = QLineEdit(self)
        self.textbox.setReadOnly(True)

        # Create textbox 2
        self.textbox2 = QLineEdit(self)
        self.textbox2.setReadOnly(True)

        # Create button
        self.button = QPushButton('Load file 1', self)
        self.button.setToolTip('Click here to browse for the first data file')
        self.button.clicked.connect(self.on_click)

        # Create button 2
        self.button2 = QPushButton('Load file 2', self)
        self.button2.setToolTip('Click here to browse for the first data file')
        self.button2.clicked.connect(self.on_click)

        grid = QGridLayout()

        grid.addWidget(self.textbox, 0, 0, 0, 3)
        grid.addWidget(self.textbox2, 0, 3, 0, 3)
        grid.addWidget(self.button, 1, 1, 1, 1)
        grid.addWidget(self.button2, 1, 4, 1, 1)

        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top, self.width, self.height)

        self.centralWidget().setLayout(grid)
        self.show()

    def openFileNameDialog(self):
        options = QFileDialog.Options()
        options |= QFileDialog.DontUseNativeDialog
        fileName, _ = QFileDialog.getOpenFileName(self, "QFileDialog.getOpenFileName()", "",
                                                  "All Files (*);;Comma seperated files (*.csv)", options=options)
        if fileName:
            self.textbox.setText(fileName)
            print(fileName)

    @pyqtSlot()
    def on_click(self):
        self.openFileNameDialog()
        print('PyQt5 button click')

if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = App()
    sys.exit(app.exec_())

if __name__ == '__main__':
    main()

1 个答案:

答案 0 :(得分:0)

您必须在第2行中建立一个Stretch,但是在此之前,您必须更正以下行的rowSpan:

grid.addWidget(self.textbox, 0, 0, 0, 3)
grid.addWidget(self.textbox2, 0, 3, 0, 3)

要了解,我们来回顾一下the docs

  

无效QGridLayout :: addWidget(QWidget * widget,int fromRow,int   fromColumn,int rowSpan,int columnSpan,Qt :: Alignment对齐=   ...)

     

这是一个重载函数。

     

此版本将给定的小部件添加到单元格网格,跨多个   行/列。该单元格将从fromRow开始,fromColumn跨越   rowSpan行和columnSpan列。小部件将具有给定的   对齐。

     

如果rowSpan和/或columnSpan为-1,则小部件将分别扩展到底部和/或右侧。

也就是说,rowSpan指示窗口小部件将占据多少行,但是您将其指示为0,因此大小将不再由布局处理,而仅由位置处理,必须将其更改为1。

import sys
from PyQt5 import QtCore, QtGui, QtWidgets


class App(QtWidgets.QMainWindow):
    def __init__(self):
        super().__init__()
        self.title = 'Data visualizing'
        self.left, self.top, self.width, self.height = 50, 50, 300, 100
        self.initUI()

    def initUI(self):
        self.central_widget = QtWidgets.QWidget()
        self.setCentralWidget(self.central_widget)

        # Create textboxs
        self.textbox = QtWidgets.QLineEdit(readOnly=True)
        self.textbox2 = QtWidgets.QLineEdit(readOnly=True)

        # Create buttons
        self.button = QtWidgets.QPushButton('Load file 1', 
            toolTip = 'Click here to browse for the first data file')
        self.button.clicked.connect(self.on_click)
        self.button2 = QtWidgets.QPushButton('Load file 2',
            toolTip = 'Click here to browse for the first data file')
        self.button2.clicked.connect(self.on_click)

        grid = QtWidgets.QGridLayout(self.centralWidget())

        grid.addWidget(self.textbox, 0, 0, 1, 3)
        grid.addWidget(self.textbox2, 0, 3, 1, 3)
        grid.addWidget(self.button, 1, 1, 1, 1)
        grid.addWidget(self.button2, 1, 4, 1, 1)
        grid.setRowStretch(2, 1)

        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top, self.width, self.height)
        self.show()

    def openFileNameDialog(self):
        options = QtWidgets.QFileDialog.Options()
        options |= QtWidgets.QFileDialog.DontUseNativeDialog
        fileName, _ = QtWidgets.QFileDialog.getOpenFileName(self, "QFileDialog.getOpenFileName()", "",
                                                  "All Files (*);;Comma seperated files (*.csv)", options=options)
        if fileName:
            self.textbox.setText(fileName)
            print(fileName)

    @QtCore.pyqtSlot()
    def on_click(self):
        self.openFileNameDialog()
        print('PyQt5 button click')

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    ex = App()
    sys.exit(app.exec_())

if __name__ == '__main__':
    main()