Script showing QTreeView problem

treetest.py

# Copyright (C) 2011 Vinay Sajip. All rights reserved.

import PySide
import PySide.QtCore as QtCore
import PySide.QtGui as QtGui

Qt = QtCore.Qt

import bisect
import logging
import os
import sys

appname = os.path.splitext(os.path.basename(sys.argv[0]))[0]
logger = logging.getLogger(appname)

class TreeNode(object):
    def __init__(self, parent, name):
        self.parent = parent
        self.name = name
        self.children = []

    @property
    def path(self):
        result = [self.name]
        if self.parent and self.parent.parent:
            result.insert(0, self.parent.path)
        return '.'.join(result)

class TreeModel(QtCore.QAbstractItemModel):
    def __init__(self, parent):
        super(TreeModel, self).__init__(parent)
        self._root = TreeNode(None, '')
        self._registry = {
            '': self._root,
        }

    def columnCount(self, parent):
        return 1

    def createIndex(self, row, col, ptr):
        if ptr:
            path = ptr.path
        else:
            path = ''
        result = super(TreeModel, self).createIndex(row, col, ptr)
        logger.debug('creating index: %d, %d, %r -> %s', row, col, path, result)
        return result

    def index(self, row, column, parent):
        invindex = QtCore.QModelIndex()
        try:
            if not parent.isValid():
                result = self.createIndex(row, column, self._root)
            else:
                node = parent.internalPointer()
                result = self.createIndex(row, column, node.children[row])
        except IndexError:
            result = invindex
        return result

    def parent(self, index):
        invindex = QtCore.QModelIndex()
        result = invindex
        if index.isValid():
            node = index.internalPointer()
            if node.parent is not None:
                result = self.createIndex(0, 0, node.parent)
                parentpath = node.parent.path
            else:
                parentpath = ''
        valid = not (result is invindex)
        if valid:
            logger.debug('parent: returning %r as parent of %r', parentpath, node.path)
        return result

    def rowCount(self, parent):
        if not parent.isValid():
            result = 1
            path = ''
        else:
            node = parent.internalPointer()
            result = len(node.children)
            path = node.path
        logger.debug('rowCount: returning %d for %r', result, path)
        return result

    def data(self, index, role=Qt.DisplayRole):
        result = None
        if index.isValid():
            node = index.internalPointer()
            if role == Qt.DisplayRole:
                try:
                    result = node.name
                    if not node.parent:
                        result = 'Root node'
                except Exception:
                    pass
            elif role == Qt.ToolTipRole:
                path = node.path
                if node.parent:
                    ppath = node.parent.path
                else:
                    ppath = ''
                rc = self.rowCount(index)
                result = '%r (parent: %r, children: %d)' % (path, ppath, rc)
        return result

    def headerData(self, section, orientation, role):
        result = None
        if orientation == Qt.Horizontal and role == Qt.DisplayRole:
            result = 'PySide %s on Qt %s' % (PySide.__version__, QtCore.__version__)
        return result

    def register_node(self, name):
        logger.debug('register_node: %s', name)
        if name in self._registry:
            result = self._registry[name]
        else:
            parts = name.rsplit('.', 1)
            nodename = parts[-1]
            if len(parts) == 1:
                parent = self._root
            else:
                parent = self.register_node(parts[0])
            pindex = self.createIndex(0, 0, parent)
            names = [c.name for c in parent.children]
            pos = bisect.bisect(names, nodename)
            result = TreeNode(parent, nodename)
            self._registry[name] = result
            self.beginInsertRows(pindex, pos, pos)
            parent.children.insert(pos, result)
            self.endInsertRows()
        return result

NODES = [
    'zmq.sheila.fred.jim',
    'tcp.fred',
    'udp.jim.fred',
    'udp.jim.sheila.fred',
    'udp.jim.sheila.fred',
    'tcp.jim.fred',
    'tcp.sheila.fred.jim',
    'tcp.jim.fred',
    'udp.sheila.fred.jim',
    'zmq.fred',
    'zmq.sheila',
    'tcp.sheila.fred',
    'udp.jim.fred.sheila',
    'udp.fred.jim.sheila',
    'udp.fred.jim',
    'udp.sheila.fred.jim',
    'tcp.jim.sheila.fred',
    'zmq.jim',
    'udp.sheila.jim',
    'tcp.fred.sheila',
    'udp.fred',
    'udp.jim.sheila',
    'zmq.sheila.fred.jim',
    'tcp.fred.jim.sheila',
    'udp.fred.jim',
    'udp.fred.sheila.jim',
]

class MainWindow(QtGui.QTreeView):
    def __init__(self):
        super(MainWindow, self).__init__()
        self.tmodel = tmodel = TreeModel(self)
        self.setModel(tmodel)
        for node in NODES:
            tmodel.register_node(node)

def main():
    app = QtGui.QApplication(sys.argv)
    main = MainWindow()
    main.setWindowTitle('Tree Test')
    main.show()
    app.exec_()

if __name__ == '__main__':
    h = logging.FileHandler('%s.log' % appname, 'w')
    root = logging.getLogger()
    root.addHandler(h)
    root.setLevel(logging.DEBUG)
    main()