wxPython – GetChildrenCount() method in wx.TreeCtrl

In this article, we are going to learn about GetChildrenCount method associated with wx.TreeCtrl class of wxPython. Returns the number of items in the branch. GetChildrenCount() method takes two parameters first is item and another is recursively.

recursively is a boolean parameter, and If recursively is True, returns the total number of descendants, otherwise, only one level of children is counted. GetChildrenCount() returns int (total number of children associated with TreeCtrl item).

Syntax: wx.TreeCtrl.GetChildrenCount()

Parameters:

Parameters	Type	Description
item	wx.TreeItemId	item that we want to ensure to be visible.
recursively	boolean	fetch children recursively or not.

Example 1: 

Python

import wx


class MyTree(wx.TreeCtrl):

    def __init__(self, parent, id, pos, size, style):
        wx.TreeCtrl.__init__(self, parent, id, pos, size, style)


class TreePanel(wx.Panel):

    def __init__(self, parent):
        wx.Panel.__init__(self, parent)

        # create tree control in window
        self.tree = MyTree(self, wx.ID_ANY, wx.DefaultPosition, wx.DefaultSize,
                        wx.TR_HAS_BUTTONS)

        # CREATE TREE ROOT
        self.root = self.tree.AddRoot('root')
        self.tree.SetPyData(self.root, ('key', 'value'))

        # add item to root
        item = self.tree.AppendItem(self.root, "Item")
        item2 = self.tree.AppendItem(self.root, "Item")
        item3 = self.tree.AppendItem(item, "SubItem")
        item4 = self.tree.AppendItem(item, "SubItem")
        item5 = self.tree.AppendItem(item2, "SubItem")
        item6 = self.tree.AppendItem(item, "SubItem")

        # expand root node
        print(self.tree.GetChildrenCount(self.root, False))

        # expand all nodes of the tree
        self.tree.Expand()

        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(self.tree, 100, wx.EXPAND)
        self.SetSizer(sizer)


class MainFrame(wx.Frame):

    def __init__(self):
        wx.Frame.__init__(self, parent = None, title ='TreeCtrl Demo')
        panel = TreePanel(self)
        self.Show()


if __name__ == '__main__':
    app = wx.App(redirect = False)
    frame = MainFrame()
    app.MainLoop()

Output:

2

Example 2:

Python

import wx


class MyTree(wx.TreeCtrl):

    def __init__(self, parent, id, pos, size, style):
        wx.TreeCtrl.__init__(self, parent, id, pos, size, style)


class TreePanel(wx.Panel):

    def __init__(self, parent):
        wx.Panel.__init__(self, parent)

        # create tree control in window
        self.tree = MyTree(self, wx.ID_ANY, wx.DefaultPosition, wx.DefaultSize,
                        wx.TR_HAS_BUTTONS)

        # CREATE TREE ROOT
        self.root = self.tree.AddRoot('root')
        self.tree.SetPyData(self.root, ('key', 'value'))

        # add item to root
        item = self.tree.AppendItem(self.root, "Item")
        item2 = self.tree.AppendItem(self.root, "Item")
        item3 = self.tree.AppendItem(item, "SubItem")
        item4 = self.tree.AppendItem(item, "SubItem")
        item5 = self.tree.AppendItem(item2, "SubItem")
        item6 = self.tree.AppendItem(item, "SubItem")

        # expand root node
        print(self.tree.GetChildrenCount(self.root, True))

        # expand all nodes of the tree
        self.tree.ExpandAllChildren(item)

        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(self.tree, 100, wx.EXPAND)
        self.SetSizer(sizer)


class MainFrame(wx.Frame):

    def __init__(self):
        wx.Frame.__init__(self, parent = None, title ='TreeCtrl Demo')
        panel = TreePanel(self)
        self.Show()


if __name__ == '__main__':
    app = wx.App(redirect = False)
    frame = MainFrame()
    app.MainLoop()

Output:

6