wxPython – wx.TreeCtrl 中的 CollapseAll() 方法

在这篇特别的文章中，我们将学习与 wxPython 的 wx.TreeCtrl 类关联的 CollapseAll() 方法。 CollapseAll() 方法类似于 Collapse() 方法，但 Collapse() 方法仅折叠给定项目，而 CollapseAll() 方法折叠根项目。
CollapseAll() 方法不需要任何参数。

Syntax: 
wx.TreeCtrl.CollapseAll(Self)

Parameters: 
No arguments are required by CollapseAll() method.
 

代码示例：

Python3

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
        self.tree = MyTree(self, wx.ID_ANY, wx.DefaultPosition, (100, 70),
                           wx.TR_HAS_BUTTONS)
  
        # Add root to Tree Control
        self.root = self.tree.AddRoot('Something goes here')
  
        # Add item to root
        itm = self.tree.AppendItem(self.root, 'Operating Systems')
  
        # Add item to 'itm'
        self.tree.AppendItem(itm, "Sub Item")
  
        # Expand whole tree
        self.tree.Expand(self.root)
  
        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(self.tree, 0, wx.EXPAND)
        self.SetSizer(sizer)
  
        # Add button in frame
        self.btn = wx.Button(self, 1, "Collapse", (10, 100))
        # Bind event function with button
        self.btn.Bind(wx.EVT_BUTTON, self.onclick)
  
    def onclick(self, e):
        # Collapse root of tree
        self.tree.CollapseAll()
  
  
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()

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