Python Tkinter：获取树节点信息

Question

Python 2.7 Linux

我只是在 Tkinter.Canvas 中使用 idlelib.TreeWidget 来创建一棵树，没有别的。

如何获取所选树节点的信息（例如名称）？我需要稍后访问此信息。

我可以在选择/双击画布时调用一个函数，但不确定如何使用树节点：

self.canvas.bind('<Double-Button-1>', self.onSave)

请运行以下代码（注意有2棵树，每个Canvas中有1棵树）：

from Tkinter import Tk, Frame, BOTH, Canvas
from xml.dom.minidom import parseString
from idlelib.TreeWidget import TreeItem, TreeNode

class DomTreeItem(TreeItem):
   def __init__(self, node):
      self.node = node
   def GetText(self):
      node = self.node
      if node.nodeType == node.ELEMENT_NODE:
         return node.nodeName
      elif node.nodeType == node.TEXT_NODE:
         return node.nodeValue
   def IsExpandable(self):
      node = self.node
      return node.hasChildNodes()
   def GetSubList(self):
      parent = self.node
      children = parent.childNodes
      prelist = [DomTreeItem(node) for node in children]
      itemlist = [item for item in prelist if item.GetText().strip()]
      return itemlist

data = '''
<angel>
 <digital_core>
  <radio_top>d</radio_top>
  <uart_top>e</uart_top>
 </digital_core>
 <digital_core>
  <c>f</c>
 </digital_core>
</angel>
'''
class Application(Frame):

   def __init__(self, parent):
      Frame.__init__(self, parent, background = "white")
      self.parent = parent

      # Maximize window
      self.screenWidth = self.parent.winfo_screenwidth() - 5
      self.screenHeight = self.parent.winfo_screenheight() - 110
      self.parent.geometry('%dx%d+%d+%d' % (self.screenWidth, self.screenHeight, 0, 0))
      self.parent.resizable(0, 0)

      dom = parseString(data)
      item = DomTreeItem(dom.documentElement)
      self.canvas = Canvas(self, bg = "cyan")
      self.canvas.grid(column = 0, row = 0, rowspan = 2, sticky = 'NSWE', padx = 5, pady = 5)
      node = TreeNode(self.canvas, None, item)
      node.update()

      self.canvas2 = Canvas(self, bg = "yellow")
      self.canvas2.grid(column = 1, row = 0, rowspan = 2, sticky = 'NSWE', padx = 5, pady = 5)
      node2 = TreeNode(self.canvas2, None, item)
      node2.update()

      parent.configure(bg = "black")
      self.pack(fill = BOTH, expand = True, padx = 20, pady = 20)

def main():
   root = Tk()
   Application(root)
   root.mainloop()

if __name__ == '__main__':
   main()  

Answer 1

DanGar 的回答很有帮助，但不是我想要的。

TreeItem 已经内置了 GetSelectedIconName 和 OnDoubleClick 函数，所以我在修改后的类中使用它来获取选择的名称：

class DomTreeItem(TreeItem):
   def __init__(self, node):
      self.node = node
   def GetText(self):
      node = self.node
      if node.nodeType == node.ELEMENT_NODE:
         return node.nodeName
      elif node.nodeType == node.TEXT_NODE:
         return node.nodeValue
   def IsExpandable(self):
      node = self.node
      return node.hasChildNodes()
   def GetSubList(self):
      parent = self.node
      children = parent.childNodes
      prelist = [DomTreeItem(node) for node in children]
      itemlist = [item for item in prelist if item.GetText().strip()]
      return itemlist
   def GetSelectedIconName(self):
      print self.node.nodeName
   def OnDoubleClick(self):
      print "double-clicked"

Answer 2

我见过的最直接的方法是访问TreeNode 的字段以检索传递给TreeNode 构造函数的内容。

例如，

node.parent
node.canvas
node.item

要从DomTreeItem获取文本，您可以这样做

node.item.GetText()

您还可以通过查看中的方法获得更多信息

dir(node.item)