问题描述
限时送ChatGPT账号..我在查询 (Python) ttk.Treeview
item
的 open
选项时遇到了不良行为.可以通过执行以下操作来设置节点 (item
) 的可见性:
I encounter untoward behavior when querying the open
option of a (Python) ttk.Treeview
item
. The visibility of a node (item
) can be set by doing something like:
tree.item(someItemID, open=True) # or
tree.item(someItemID, open=False)
我的假设是可以查询 open
选项以获得布尔值 True/False.然而,情况似乎并非如此.考虑这个脚本:
And my assumption is the open
option can be queried to get a boolean True/False. However, this doesn't appear to be the case. Consider this script:
from Tkinter import *
from ttk import Treeview
def check_state():
for row in tree.get_children():
opened = tree.item(row, option='open')
print row, 'opened:', opened, '(type: %s)' % str(type(opened)), 'Got:',
if not opened:
print 'False (bool)'
elif opened == 'true':
print 'equal to string "true"'
elif opened == 'false':
print 'equal to string "false"'
elif opened:
print 'True (bool)'
else:
print 'something entirely different(!)'
print
win = Frame()
tree = Treeview(win)
win.pack()
tree.pack()
Button(win, text='View state', command=check_state).pack()
level1 = ['C:\\dir1', 'C:\\dir2', 'C:\\dir3']
level2 = ['one.txt', 'two.txt', 'three.txt']
for L in level1:
iid = tree.insert('', END, text=L)
for M in level2:
tree.insert(iid, END, text=M)
win.mainloop()
运行时,它会显示一个填充有假目录和文件名的小型 Treeview 控件.在打开或关闭任何顶级节点之前,按下按钮将open
选项状态转储到标准输出.应该是这样的:
When run, it displays a small Treeview control populated with fake directories and file names. Before opening or closing any of the top-level nodes, press the button to dump the open
option states to stdout. Should look like this:
I001 opened: 0 (type: <type 'int'>) Got: False (bool)
I005 opened: 0 (type: <type 'int'>) Got: False (bool)
I009 opened: 0 (type: <type 'int'>) Got: False (bool)
现在打开其中一个节点并再次按下按钮.现在它转储了:
Now open one of the nodes and press the button again. Now it dumps:
I001 opened: 0 (type: <type 'int'>) Got: False (bool)
I005 opened: 0 (type: <type 'int'>) Got: False (bool)
I009 opened: true (type: <type '_tkinter.Tcl_Obj'>) Got: True (bool)
最后,关闭所有节点并再次按下按钮.它转储:
Finally, close all nodes and press the button once more. It dumps:
I001 opened: 0 (type: <type 'int'>) Got: False (bool)
I005 opened: 0 (type: <type 'int'>) Got: False (bool)
I009 opened: false (type: <type '_tkinter.Tcl_Obj'>) Got: True (bool)
让我印象深刻的事情:
不一致:虽然初始化为int
s,但后来赋值的是_tkinter
对象布尔比较失败:尽管 _tkinter
对象呈现为字符串true"或false",但它们不会计算为 True 和 False(例如打印的 _tkinter
对象作为假"评估为真)
Inconsistency: while initialized to int
s, later the values assigned are _tkinter
objects
Boolean comparison failure: despite the _tkinter
objects rendering as the strings 'true' or 'false' they do not evaluate to True and False (e.g. the _tkinter
object printed as "false" evaluated as True)
有人知道是什么吗?如何可靠地确定 Treeview 项的打开/关闭状态?
Anyone know what gives? How can I reliably determine the open/closed state of a Treeview item?
推荐答案
有一个 tkinter 选项:tkinter.wantObjects
,有些人提议将其更改为 False.它应该使 Tk 不使用 TCL_objs.但是当我尝试它时,TreeView 看起来坏了.
There was a tkinter option: tkinter.wantObjects
that some people offered to change to False. It should make Tk to do not use TCL_objs. But when I tried it the TreeView looked broken.
作为一种解决方法,我以如下方式使用 BooleanVar:
As a workaround I used BooleanVar in way like this:
open_opt = BooleanVar()
for row in tree.get_children():
open_opt.set(str(tree.item(row, option='open')))
opened = open_opt.get()
这种方式对我来说似乎有效
This way seemed working to me
这篇关于检索 ttk.Treeview 项目的“打开"选项作为布尔值的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
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