def parent(self, index=None):
"""Find the index of the parent of the item at a given index."""
try:
parent = self._index_to_item(index).parent
return self.createIndex(parent.row, 0, parent)
except:
# Something went wrong with finding the parent so return an invalid index
return QtCore.QModelIndex()
def index(self, row, column, parent_index):
"""Return the index of the <row>th child of parent
:type row: int
:type column: int
:type parent: QtCore.QModelIndex
"""
try:
parent = self._index_to_item(parent_index)
return self.createIndex(row, column, parent.children[row])
except:
return QtCore.QModelIndex()