Hmm, the error is still a bit mysterious to me. I call SetPyData on every item I insert into the tree. Interestingly enough, the assertion does not show when I select items via the keyboard. It only happens when I select an item with the left mouse button.
I inserted some code like this here:
if I select the item with the keyboard, m_pItem has some value and IsOk() also returns True. If I select the very same item via a mouse click the assertion is given. So it seems to be that item returned by evt.GetItem() is not valid if selected with the mouse.
If I bind EVT_TREE_ITEM_RIGHT_CLICK, then evt.GetItem() also returns the correct value.
I don't bind any other events like ON_LEFT_DOWN or something like that.
The tree ctrl is created via XRC and the panel it is on, is also loaded via XRC with code like this:
That shouldn't create any problem I hope.
I am on Win XP SP2 and I am still clueless why this happens.
I could reproduce the bug with the TreeCtrl demo, at the end of the mail is the code.
···
Am 18.10.2006, 23:47 Uhr, schrieb Robin Dunn <robin@alldunn.com>:
Nitro wrote:
Hello,
I get tracebacks such as this one:
Traceback (most recent call last):
File "./Plugins\canvas.py", line 204, in OnTreeISelChanged
node = self.tree.GetPyData(item)
File "D:\Python24\Lib\site-packages\wx-2.7.0-msw-unicode\wx\_controls.py", lin
e 5237, in GetItemPyData
return _controls_.TreeCtrl_GetItemPyData(*args, **kwargs)
wx._core.PyAssertionError: C++ assertion "param" failed at ..\..\src\msw\treectr
l.cpp(1062) in wxTreeCtrl::SetItemData(): failed to change tree items data
It happens on this simple code:
def OnTreeISelChanged(self, evt):
item = evt.GetItem()
node = self.tree.GetPyData(item)
Any idea why this happens? Why is the traceback referring to SetItemData, I am just calling *Get*PyData?
PyObject* GetItemPyData(const wxTreeItemId& item) {
wxPyTreeItemData* data = (wxPyTreeItemData*)self->GetItemData(item);
if (data == NULL) {
data = new wxPyTreeItemData();
data->SetId(item); // set the id
self->SetItemData(item, data);
}
return data->GetData();
}
If the item has no data then a new wxPyTreeItemData object is created and assigned to the item, using None for the Python object to store a reference to.
#---------------------------------------------------------------------------
class MyTreeCtrl(wx.TreeCtrl):
def __init__(self, parent, id, pos, size, style, log):
wx.TreeCtrl.__init__(self, parent, id, pos, size, style)
self.log = log
def OnCompareItems(self, item1, item2):
t1 = self.GetItemText(item1)
t2 = self.GetItemText(item2)
#self.log.WriteText('compare: ' + t1 + ' <> ' + t2 + '\n')
if t1 < t2: return -1
if t1 == t2: return 0
return 1
#---------------------------------------------------------------------------
class TestTreeCtrlPanel(wx.Panel):
def __init__(self, parent, log):
# Use the WANTS_CHARS style so the panel doesn't eat the Return key.
wx.Panel.__init__(self, parent, -1, style=wx.WANTS_CHARS)
self.Bind(wx.EVT_SIZE, self.OnSize)
self.log = log
tID = wx.NewId()
self.tree = MyTreeCtrl(self, tID, wx.DefaultPosition, wx.DefaultSize,
wx.TR_HAS_BUTTONS
> wx.TR_EDIT_LABELS
> wx.TR_MULTIPLE
#| wx.TR_HIDE_ROOT
, self.log)
isz = (16,16)
il = wx.ImageList(isz[0], isz[1])
fldridx = il.Add(wx.ArtProvider_GetBitmap(wx.ART_FOLDER, wx.ART_OTHER, isz))
fldropenidx = il.Add(wx.ArtProvider_GetBitmap(wx.ART_FILE_OPEN, wx.ART_OTHER, isz))
fileidx = il.Add(wx.ArtProvider_GetBitmap(wx.ART_NORMAL_FILE, wx.ART_OTHER, isz))
smileidx = il.Add(images.getSmilesBitmap())
self.tree.SetImageList(il)
self.il = il
# NOTE: For some reason tree items have to have a data object in
# order to be sorted. Since our compare just uses the labels
# we don't need any real data, so we'll just use None below for
# the item data.
class X(object):
def __init__(self):
self.f = 7
someClass = X()
self.root = self.tree.AddRoot("The Root Item")
self.tree.SetPyData(self.root, 'root')
self.tree.SetItemImage(self.root, fldridx, wx.TreeItemIcon_Normal)
self.tree.SetItemImage(self.root, fldropenidx, wx.TreeItemIcon_Expanded)
for x in range(15):
someClass = X()
child = self.tree.AppendItem(self.root, "Item %d" % x)
self.tree.SetPyData(child, someClass)
self.tree.SetItemImage(child, fldridx, wx.TreeItemIcon_Normal)
self.tree.SetItemImage(child, fldropenidx, wx.TreeItemIcon_Expanded)
for y in range(5):
last = self.tree.AppendItem(child, "item %d-%s" % (x, chr(ord("a")+y)))
self.tree.SetPyData(last, None)
self.tree.SetItemImage(last, fldridx, wx.TreeItemIcon_Normal)
self.tree.SetItemImage(last, fldropenidx, wx.TreeItemIcon_Expanded)
for z in range(5):
item = self.tree.AppendItem(last, "item %d-%s-%d" % (x, chr(ord("a")+y), z))
self.tree.SetPyData(item, None)
self.tree.SetItemImage(item, fileidx, wx.TreeItemIcon_Normal)
self.tree.SetItemImage(item, smileidx, wx.TreeItemIcon_Selected)
self.tree.Expand(self.root)
#self.Bind(wx.EVT_TREE_ITEM_EXPANDED, self.OnItemExpanded, self.tree)
#self.Bind(wx.EVT_TREE_ITEM_COLLAPSED, self.OnItemCollapsed, self.tree)
self.Bind(wx.EVT_TREE_SEL_CHANGED, self.OnSelChanged, self.tree)
#self.Bind(wx.EVT_TREE_BEGIN_LABEL_EDIT, self.OnBeginEdit, self.tree)
#self.Bind(wx.EVT_TREE_END_LABEL_EDIT, self.OnEndEdit, self.tree)
#self.Bind(wx.EVT_TREE_ITEM_ACTIVATED, self.OnActivate, self.tree)
#self.tree.Bind(wx.EVT_LEFT_DCLICK, self.OnLeftDClick)
#self.tree.Bind(wx.EVT_RIGHT_DOWN, self.OnRightDown)
#self.tree.Bind(wx.EVT_RIGHT_UP, self.OnRightUp)
def OnRightDown(self, event):
pt = event.GetPosition();
item, flags = self.tree.HitTest(pt)
if item:
self.log.WriteText("OnRightClick: %s, %s, %s\n" %
(self.tree.GetItemText(item), type(item), item.__class__))
self.tree.SelectItem(item)
def OnRightUp(self, event):
pt = event.GetPosition();
item, flags = self.tree.HitTest(pt)
if item:
self.log.WriteText("OnRightUp: %s (manually starting label edit)\n"
% self.tree.GetItemText(item))
self.tree.EditLabel(item)
def OnBeginEdit(self, event):
self.log.WriteText("OnBeginEdit\n")
# show how to prevent edit...
item = event.GetItem()
if item and self.tree.GetItemText(item) == "The Root Item":
wx.Bell()
self.log.WriteText("You can't edit this one...\n")
# Lets just see what's visible of its children
cookie = 0
root = event.GetItem()
(child, cookie) = self.tree.GetFirstChild(root)
while child.IsOk():
self.log.WriteText("Child [%s] visible = %d" %
(self.tree.GetItemText(child),
self.tree.IsVisible(child)))
(child, cookie) = self.tree.GetNextChild(root, cookie)
event.Veto()
def OnEndEdit(self, event):
self.log.WriteText("OnEndEdit: %s %s\n" %
(event.IsEditCancelled(), event.GetLabel()) )
# show how to reject edit, we'll not allow any digits
for x in event.GetLabel():
if x in string.digits:
self.log.WriteText("You can't enter digits...\n")
event.Veto()
return
def OnLeftDClick(self, event):
pt = event.GetPosition();
item, flags = self.tree.HitTest(pt)
if item:
self.log.WriteText("OnLeftDClick: %s\n" % self.tree.GetItemText(item))
parent = self.tree.GetItemParent(item)
if parent.IsOk():
self.tree.SortChildren(parent)
event.Skip()
def OnSize(self, event):
w,h = self.GetClientSizeTuple()
self.tree.SetDimensions(0, 0, w, h)
def OnItemExpanded(self, event):
item = event.GetItem()
if item:
self.log.WriteText("OnItemExpanded: %s\n" % self.tree.GetItemText(item))
def OnItemCollapsed(self, event):
item = event.GetItem()
if item:
self.log.WriteText("OnItemCollapsed: %s\n" % self.tree.GetItemText(item))
def OnSelChanged(self, event):
try:
item = self.item = event.GetItem()
self.log.WriteText('XXX' + str(item.IsOk()) )
self.log.WriteText( str(self.tree.GetPyData(item)) )
self.log.WriteText('YYY')
except:
import traceback
self.log.WriteText(traceback.format_exc())
if self.item:
self.log.WriteText("OnSelChanged: %s\n" % self.tree.GetItemText(self.item))
if wx.Platform == '__WXMSW__':
self.log.WriteText("BoundingRect: %s\n" %
self.tree.GetBoundingRect(self.item, True))
#items = self.tree.GetSelections()
#print map(self.tree.GetItemText, items)
event.Skip()
def OnActivate(self, event):
if self.item:
self.log.WriteText("OnActivate: %s\n" % self.tree.GetItemText(self.item))
#---------------------------------------------------------------------------
def runTest(frame, nb, log):
win = TestTreeCtrlPanel(nb, log)
return win
#---------------------------------------------------------------------------
overview = """\
A TreeCtrl presents information as a hierarchy, with items that may be
expanded to show further items. Items in a tree control are referenced by
wx.TreeItemId handles.
"""
if __name__ == '__main__':
import sys,os
import run
run.main(['', os.path.basename(sys.argv[0])] + sys.argv[1:])