wxPython wx.TreeCtrl中的CollapseAndReset()方法

在这篇文章中，我们将学习wxPython中的另一个函数，即与wxPython的wx.TreeCtrl类相关的CollapseAndReset()方法。CollapseAndReset()函数简单地折叠了一个特定的项目并删除了它的所有子项。

它接受TreeItemId作为参数。

语法： wx.TreeCtrl.CollapseAndReset(Self, item)

代码示例 。

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,
                                 (150,150), wx.TR_HAS_BUTTONS)
  
        # Add root to Tree Control
        self.root = self.tree.AddRoot('Root')
  
        # Add item to root
        self.itm = self.tree.AppendItem(self.root, 'Item')
  
        # Add item to 'itm'
        self.itm2 = self.tree.AppendItem(self.itm, "Sub Item")
  
        # Add child item to itm2
        self.itm3 = self.tree.AppendItem(self.itm2, "Another Item")
  
        # Expand whole tree
        self.tree.ExpandAll()
  
        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 all children of itm recursively
        self.tree.CollapseAndReset(self.itm)
  
  
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()