Type ExpansionState
object
--+
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TreeAPIHarmonizer
--+
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object
--+ |
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TreeHelper
--+
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ExpansionState
This is a mixin class that can be used to save and restore
the expansion state (i.e. which items are expanded and which items
are collapsed) of a tree. It can be mixed in with wx.TreeCtrl,
wx.gizmos.TreeListCtrl, or wx.lib.customtree.CustomTreeCtrl.
To use it derive a new class from this class and one of the tree
controls, e.g.:
class MyTree(ExpansionState, wx.TreeCtrl):
...
By default, ExpansionState uses the position of tree items in the tree
to keep track of which items are expanded. This should be sufficient
for the simple scenario where you save the expansion state of the tree
when the user closes the application or file so that you can restore
the expansion state when the user start the application or loads that
file for the next session.
If you need to add or remove items between the moments of saving and
restoring the expansion state (e.g. in case of a multi-user application)
you must override GetItemIdentity so that saving and loading of the
expansion doesn't depend on the position of items in the tree, but
rather on some more stable characteristic of the underlying domain
object, e.g. a social security number in case of persons or an isbn
number in case of books.
Method Summary |
list of expanded items |
GetExpansionState ()
Expanded items
are coded as determined by the result of GetItemIdentity(item). |
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GetExpansionStateOfChildren(self,
item)
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GetExpansionStateOfItem(self,
item)
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GetItemIdentity (self,
item)
Return a hashable object that represents the identity of the
item. |
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SetExpansionState (listOfExpandedItems)
Expands all tree items
whose identity, as determined by GetItemIdentity(item), is present
in the list and collapses all other tree items. |
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SetExpansionStateOfChildren(self,
listOfExpandedItems,
item)
|
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SetExpansionStateOfItem(self,
listOfExpandedItems,
item)
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GetExpansionState()
Expanded items
are coded as determined by the result of GetItemIdentity(item).
-
- Returns:
-
list of expanded items
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GetItemIdentity(self,
item)
Return a hashable object that represents the identity of the
item. By default this returns the position of the item in the
tree. You may want to override this to return the item label
(if you know that labels are unique and don't change), or return
something that represents the underlying domain object, e.g.
a database key.
-
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SetExpansionState(listOfExpandedItems)
Expands all tree items
whose identity, as determined by GetItemIdentity(item), is present
in the list and collapses all other tree items.
-
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