python 从子部件调用父方法

python call parent method from child widget

我正在尝试从子小部件 treeView 调用父方法 printName 但是得到像

这样的错误
  1. AttributeError: 'QSplitter' 对象没有属性 'printName'
  2. QObject::startTimer:QTimer 只能用于以 QThread 启动的线程

为什么 parent 指的是 QSplitter?

TreeView 的父级应该是 compositeWidget,因为 TreeView 是在 compositeWidget

中创建的

代码:

from PyQt4.QtCore import *
from PyQt4.QtGui import *
import sys


class MainExample(QMainWindow):

    def __init__(self, parent=None):
        super(MainExample, self).__init__(parent)
        self.initUI()

    def initUI(self):
        self.mainWidget = compositeWidget(self)
        self.setCentralWidget(self.mainWidget)
        self.mainWidget.treeView.setPath('D:\DATA')
        self.setGeometry(300, 300, 300, 200)


class TreeView(QTreeView):

    def __init__(self, parent):
        super(TreeView, self).__init__(parent)
        self.clicked.connect(self.on_treeView_clicked)

    @pyqtSlot(QModelIndex)
    def on_treeView_clicked(self, index):
        indexItem = self.FileSystemModel.index(index.row(), 0, index.parent())
        filePath = self.FileSystemModel.filePath(indexItem)
        self.parent().printName(filePath)
        #

    def setPath(self, path):
        self.FileSystemModel = QFileSystemModel()
        self.FileSystemModel.setFilter(QDir.Dirs | QDir.NoDotAndDotDot)
        self.FileSystemModel.setRootPath(path)
        self.setModel(self.FileSystemModel)
        index = self.FileSystemModel.index(path)
        self.setRootIndex(index)


class compositeWidget(QWidget):

    def __init__(self, parent):
        super(compositeWidget, self).__init__(parent)
        self.treeView = TreeView(self)
        self.frame = QFrame()
        splitterHorizontal = QSplitter(Qt.Horizontal)
        splitterHorizontal.addWidget(self.treeView)
        splitterHorizontal.addWidget(self.frame)
        splitterHorizontal.setSizes([10, 190])
        self.layout = QHBoxLayout(self)
        self.layout.addWidget(splitterHorizontal)
        self.setLayout(self.layout)

    def printName(self):
        print 'fileName'


def main():

    app = QApplication(sys.argv)
    ex = MainExample()
    ex.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

QTreeView 在 QSplitter 下 在 compositeWidget 下。 您需要致电

self.parent().parent().printName(filePath)

不幸的是,这似乎没有记录在案(这似乎有点疏忽),但与 Qt 中的其他 addWidget() 方法(如 QLayout.addWidget())一样,QSplitter.addWidget() 方法通过成为其父项来获取子项的所有权。

这就是 Treeview.parent() 返回 QSplitter 的原因。您应该使用另一种方式来访问您想要的父级(例如,明确存储对您传递给构造函数的父级的引用)

class TreeView(QTreeView):

    def __init__(self, parent):
        super(TreeView, self).__init__(parent)
        self.clicked.connect(self.on_treeView_clicked)
        self.composite_widget = parent

    @pyqtSlot(QModelIndex)
    def on_treeView_clicked(self, index):
        indexItem = self.FileSystemModel.index(index.row(), 0, index.parent())
        filePath = self.FileSystemModel.filePath(indexItem)
        self.composite_widget.printName(filePath)
        #

    def setPath(self, path):
        self.FileSystemModel = QFileSystemModel()
        self.FileSystemModel.setFilter(QDir.Dirs | QDir.NoDotAndDotDot)
        self.FileSystemModel.setRootPath(path)
        self.setModel(self.FileSystemModel)
        index = self.FileSystemModel.index(path)
        self.setRootIndex(index)