使用 QGridLayout 在 PyQt5 中进行简单聊天的 Gui

Gui for a simple chat in PyQt5 using QGridLayout

我一直在研究 PyQt5,最近决定为一个简单的聊天客户端制作一个图形用户界面。这是我的模型:

我使用了 QGridLayout,这是我得到的:

如何减小底部 QTextEdit 的大小,使其有 2-3 行可用,并使 QPushButton 变大?

我的程序:

import sys
from PyQt5.QtWidgets import (QMainWindow, QAction, QApplication, QDesktopWidget,
                             QDialog, QTextEdit, QGridLayout, QPushButton, QWidget)
from PyQt5.QtGui import QIcon

class Chat(QMainWindow):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        self.populateUI()

        self.resize(400, 400)
        self.center()
        self.setWindowTitle('Simple Chat')
        self.show()

    def center(self):
        qr = self.frameGeometry()
        cp = QDesktopWidget().availableGeometry().center()
        qr.moveCenter(cp)
        self.move(qr.topLeft())

    def populateUI(self):
        self.createMenu()
        self.statusBar()
        centralWidget = CentralWidget()
        self.setCentralWidget(centralWidget)

    def createMenu(self):
        menuBar = self.menuBar()

        fileMenu = menuBar.addMenu('&File')
        fileMenu.addAction(self.createExitAction())

        helpMenu = menuBar.addMenu('&Help')
        helpMenu.addAction(self.createAboutAction())

    def createExitAction(self):
        exitAction = QAction(QIcon('exit.png'), '&Exit', self)
        exitAction.setShortcut('Ctrl+Q')
        exitAction.setStatusTip('Exit application')
        exitAction.triggered.connect(self.close)
        return exitAction

    def createAboutAction(self):
        aboutAction = QAction(QIcon('info.png'), '&About', self)
        aboutAction.setShortcut('Ctrl+H')
        aboutAction.setStatusTip('Information about the program')
        aboutAction.triggered.connect(self.createAboutDialog)
        return aboutAction

    def createAboutDialog(self):
        dialog = QDialog(self)
        dialog.setWindowTitle('About')
        dialog.setWindowIcon(QIcon('info.png'))
        dialog.resize(200, 200)
        dialog.exec_()

class CentralWidget(QWidget):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        ribbon = QTextEdit()
        chat = QTextEdit()
        sendBtn = QPushButton('Send')

        grid = QGridLayout()
        grid.setSpacing(3)
        grid.addWidget(ribbon, 0, 0, 1, 3)
        grid.addWidget(chat, 1, 0, 1, 1)
        grid.addWidget(sendBtn, 1, 2)

        self.setLayout(grid)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    chat = Chat()
    sys.exit(app.exec_())

我猜你在照顾 setFixedSize(QSize size) of QWidget

您首先需要根据要显示的行数为底部文本编辑设置固定高度。这里还需要考虑到frame和document margin:

    def initUI(self):
        ...
        chat.setFixedHeight(
            (chat.fontMetrics().lineSpacing() * 3) +
            (chat.document().documentMargin() * 2) +
            (chat.frameWidth() * 2) - 1
            )

然后您需要更改按钮的大小策略,使其垂直展开:

        policy = sendBtn.sizePolicy()
        policy.setVerticalPolicy(QSizePolicy.MinimumExpanding)
        sendBtn.setSizePolicy(policy)

最后,您需要在第一行和第一列设置拉伸因子,以便文本编辑占据所有可用空间space:

        grid.setRowStretch(0, 1)
        grid.setColumnStretch(0, 1)