wxPython – ExpandAllChildren() method in wx.TreeCtrl

In this article, we are going to learn about ExpandAllChildren() method associated with wx.TreeCtrl class of wxPython. ExpandAllChildren() method is used in order to expand all the nodes that comes under a particular item that is passed as a parameter in the method. Basically, this method expands the given item and all its children recursively.

This function takes the tree node item as a parameter to whom we want to expand recursively.

Syntax:  wx.TreeCtrl.ExpandAllChildren(self,i tem)

Parameters:

Parameter	Type	Description
item	wx.TreeItemId	Item that we want to associate editlabel with.

Code Example:

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
        self.tree.Expand(self.root)

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

        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(self.tree, 0, 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: