PyQt4 QTreeWidget parent and child indexes

Question

I created PyQt4 QTreeWidget and added following QTreeWidgetItem structure.

treeWidget = QTreeWidget()

twi = QTreeWidgetItem(['Level_1'])
twi.addChild( QTreeWidgetItem( ['SubLevel_1_1'] ) )
twi.addChild( QTreeWidgetItem( ['SubLevel_1_2'] ) )
twi.addChild( QTreeWidgetItem( ['SubLevel_1_3'] ) )
twi.addChild( QTreeWidgetItem( ['SubLevel_1_4'] ) )

treeWidget.addTopLevelItem( twi )

I want to get parent (top level item) and child indexes when selected child item.

Answer 1

First of all, if you are planning on accessing a widget from a method, I would make it a property of your parenting widget/GUI, so

self.treeWidget = QTreeWidget()

Then in your example you forgot to add the top level item

self.treeWidget.insertTopLevelItem(0,twi)

To find out your current selection you can then add something like this:

def getCurrentItems(self):

    """Returns Current top level item and child index.
    If no child is selected, returns -1. 
    """

    #Check if top level item is selected or child selected
    if self.treeWidget.indexOfTopLevelItem(self.treeWidget.currentItem())==-1:
        return self.treeWidget.currentItem().parent(),self.treeWidget.currentItem().parent().indexOfChild(self.treeWidget.currentItem())
    else:   
        return self.treeWidget.currentItem(),-1

And then connect the method via:

self.treeWidget.itemActivated.connect(self.getCurrentItems)

Hope that helps.

Answer 2

I've solved this by iterating from the current selected item all the way up to trace the parent of the item using a while loop. Note that I'm using PyQt5/PySide2 for this code.

treewidget = self.ui.treeWidget_size
# Initialise an Empty list to store the indexes
level_list = []

current_item = treewidget.currentItem()
current_index = treewidget.indexFromItem(current_item)

if current_index.isValid():
    level_list.append(current_index.row())

# Iterate through all the item's parents
while current_index.isValid():
    current_item = treewidget.itemFromIndex(current_index.parent())

    # Get the parent of the item and find the index of it's parent until we reach the top
    current_index = treewidget.indexFromItem(current_item)
    if current_index.isValid():
        level_list.append(current_index.row())

#Once done getting indexes, reverse_list
level_list = level_list[::-1]