Question

我想在运行时向QVBoxLayout添加小部件。但是当我使用该布局的addWidget方法时它不起作用。然后我想是否需要用于刷新布局或应用程序的方法，但其他不需要它的代码有很好的代表性。

这是我的代码：

import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from socket import *
from collections import deque


app = QApplication(sys.argv)

class Chatting(QWidget) :
    _name = None

    serverAddr = ('localhost', 20123)
    client = socket(AF_INET, SOCK_DGRAM)

    def __init__(self,name,):
        super(Chatting, self).__init__()

        self._name = name

        self.setWindowTitle('Chatting')
        self.setFixedWidth(645)
        self.setFixedHeight(445)

        scrollArea = QScrollArea()
        scrollArea.setVerticalScrollBarPolicy(Qt.ScrollBarAsNeeded)
        scrollArea.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
        scrollArea.setWidgetResizable(False)
        self.scrollWidget = QWidget()
        self.scrollWidget.setFixedWidth(645)
        self.scrollWidget.setFixedWidth(400)
        self.verticalLayoutTop = QVBoxLayout(self)
        self. scrollWidget.setLayout(self.verticalLayoutTop)
        scrollArea.setWidget(self.scrollWidget)

        send = QWidget()
        horizontalLayoutBottom = QHBoxLayout(self)
        self.contentEdit = QLineEdit()
        horizontalLayoutBottom.addWidget(self.contentEdit)
        self.sendButton = QPushButton('Send')
        self.sendButton.clicked.connect(self.send)
        horizontalLayoutBottom.addWidget(self.sendButton)
        send.setLayout(horizontalLayoutBottom)

        mainLayout = QVBoxLayout(self)
        mainLayout.addWidget(scrollArea)
        mainLayout.addWidget(send)

        self.setLayout(mainLayout)

        clientThread = ClientThread(client=self.client,parent=self)
        self.connect(clientThread,clientThread.signal,self.writeToMessageList)
        clientThread.start()

    def send(self):
        self.client.sendto(self._name + ' say:' + self.contentEdit.text().toUtf8(),self.serverAddr)
        self.contentEdit.setText('')

    def writeToMessageList(self,message):
        print message
        '''
           I can get data here.
           So errors happened at the following two line.
        '''
        messageLabel = QLabel(message)
        self.scrollWidget.layout().addWidget(messageLabel)

class ClientThread(QThread) :

    BUFSIZE = 1024

    _client = None

    def __init__(self,client,parent=None):
        QThread.__init__(self, parent)
        self._client = client
        self.signal = SIGNAL("signal")

    def run(self):
        self.receive()

    def receive(self):

        while True:
            data,addr = self._client.recvfrom(self.BUFSIZE)
            self.emit(self.signal,data)

if __name__ == '__main__':

     dialog = Chatting(name='Little pig')
     dialog.show()

     app.exec_()

Answer 1

我看到两个问题：

self.scrollWidget.setFixedWidth(645)
self.scrollWidget.setFixedWidth(400)

让布局控件小部件大小。

另一个问题是QVBoxLayout(self)！如果您将widget作为布局构造函数参数传递，则会立即将布局设置为给定窗口小部件，因此在您的情况下为Chatting。从那时起，这种布局就无法移动到其他小部件（你应该在日志中有一些警告）。所以修理如下：

def __init__(self,name,):
    super(Chatting, self).__init__()

    self._name = name

    self.setWindowTitle('Chatting')
    self.setFixedWidth(645)
    self.setFixedHeight(445)

    scrollArea = QScrollArea()
    scrollArea.setVerticalScrollBarPolicy(Qt.ScrollBarAsNeeded)
    scrollArea.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
    scrollArea.setWidgetResizable(False)
    self.scrollWidget = QWidget()
    self.verticalLayoutTop = QVBoxLayout()
    self. scrollWidget.setLayout(self.verticalLayoutTop)
    scrollArea.setWidget(self.scrollWidget)

    send = QWidget()
    horizontalLayoutBottom = QHBoxLayout(send)
    self.contentEdit = QLineEdit()
    horizontalLayoutBottom.addWidget(self.contentEdit)
    self.sendButton = QPushButton('Send')
    self.sendButton.clicked.connect(self.send)
    horizontalLayoutBottom.addWidget(self.sendButton)

    mainLayout = QVBoxLayout(self)
    mainLayout.addWidget(scrollArea)
    mainLayout.addWidget(send)

    clientThread = ClientThread(client=self.client,parent=self)
    self.connect(clientThread,clientThread.signal,self.writeToMessageList)
    clientThread.start()

在运行时将QLabel添加到QVBoxLayout但它在pyqt中不起作用

1 个答案: