Please add support for tooltips per cell.

The fact that tooltips are missing means that our move from GtkList to
GtkTreeView in GIMP-1.3 is a feature regression. I vote for giving
this report a higher priority.

Can't add it before 2.4. I am pretty sure this will make 2.4

I will work on getting this into 2.4.

Yes, yes, yes :-)

This would be a wonderful enhancement to the already awesome 
tree widget. And there's no easy way to implement it "externally", 
especially with the rather dry (poor?) current tooltip API.

Why do I have a funny feeling this has slipped :(

...because it has

well? any news on the $subject? we need this, guys

you might want to consider helping with it, then...

This functionality is needo to implement a tooltip showing the full path of
directories added as bookmarks in the file chooser.

See bug #137503 regarding this issue:

http://bugzilla.gnome.org/show_bug.cgi?id=137503

I also have interest in implementing this feature.

Are there some documents which describe the planned API or implementation?

As for the API I think CellRenderer needs a property "tooltip". Or do we want to
implement this for CellRendererText, only?

As for the implementation I think TreeView might override show_help. But this
shows the help for the focus location which would be wrong.

The correct (?) alternative would be to enhance Tooltips to accept a function
pointer to fetch the tip (mouse position as argument) in addtion to of a
constant string.

E.g. void gtk_tooltips_set_tip_function(GtkTooltips   *tooltips, GtkWidget    
*widget, const gchar *(fun)(GtkWidget*,int x,int y));

Looks like this touches TipsQuery, too. Sigh. 

Does a potential patch really such a deep impact on the code base?

Yes, there are some other bugs about redesigning the tooltips api, and this
would certainly fit in. Jonathan also mentioned that it would be nice to have an
easy way to set up tooltips showing the full text of an ellipsized cell.

So this bug depends on #50619: Rework tooltips (especially #86332: Support
dynamic tooltips which is marked as a duplicate of 50619).

Other related bugs are
#126807: Tooltips on treeview columns
(#56291: Handle tooltips on NO_WINDOW widgets)

I wish _I_ could mark this bug as depending on #50619
http://bugzilla.gnome.org/show_bug.cgi?id=50619 but could not figure out how to
do that.

This is funny, this Bugzilla version doesn't have then entry fields for new bugs
to depend upon/block if you are logged in.

Bug #161188 depends on this feature implemented in GTK+.

*** Bug 308615 has been marked as a duplicate of this bug. ***

Several people have asked for this in Gossip repeatedly.  
Bug #130983 depends on this.

Err... no movement in that respect here? As noted above, this is a serious feature regression from gtk1 to gtk2. The gnucash project (which has been a bit slow on the gtk2 porting side, admittantly) is now about to release their first gtk2-versions, and obviously the hundreds of tooltip explanation strings that existed in gtk1 (and were very helpful) are now no longer visible.  Is it really true that gtk2 did not keep that gtk1-feature here? So gtk2 really has a feature regression and even in gtk2.9 nobody has done anything about it? This is ... unexpected.

@Martyn: Did your workaround in bug#130983 actually fix this? If yes, gnucash would happily copy your suggestion...

Christian: The short answer is, no not really. Gnucash can certainly try it out and see if it works for your situation.

The problem was that although the tooltip updated for the GtkTreeView widget every time the selection changed, it was ok but the tooltip was incorrectly positioned so it looked weird.

Kris: can you comment on this, didn't you do some work on this when we were last together in Stockholm?  If I recall, I asked you if we could have support since so many people are crying out for it and I can't remember how far you got with it.

Yes, I've been looking at this when we were last in Stockholm.  Basically I got something working and after that I got pointed at a mail from Owen on reworking the tooltips API (which used a different, but probably better approach to solving the problem).  My plan was to read that mail and write a proposal to gtk-devel-list, but just didn't have the time to do it yet...

Any progress on this?

It just missed 2.10 and it is scheduled to land in 2.12.  The latest API proposals have been posted to gtk-devel-list over the last few months.

The new tooltips API is in gtk+ trunk now, tooltips per cell can be done now using the query-tooltip signal handler.