Re: More NSOutlineView bugs

[Matt Rice]

On 2007-02-04 09:19:24 -0800 Guenther Noack 
<address@hidden> wrote:

> Hi!
>
> Playing around with outline drag&drop, I found some other
> selection-related issues in NSOutlineView:
>
> - Inconsistency
>
> The NSOutlineView method -noteNumberOfRowsChanged forgets about the
> case where only one item is allowed to be selected. This leads to
> inconsistencies within NSTableView which result in wrongly selected
> rows in outline views. It can be fixed by adding this code snippet
> before the -setFrame call:
>
> if ([_selectedRows count] == 0) {
>   _selectedRow = -1;
> } else {
>   _selectedRow = [_selectedRows lastIndex];
> }

I really don't think that -noteNumberOfRowsChanged makes any sense for 
NSOutlineView
because its a public method, and can be called seperate from 
-reloadData
at the beginning it goes

_numberOfRows = [_items count];

If -reloadData is not called... this doesn't go to the delegate to get 
the new number of rows
well it really cant in any good way which would be more optimal than 
reloadData,
and I couldn't get this to do anything on a mac

> - More inconsistency
>
> The -reloadData method in NSTableView calls -noteNumberOfRowsChanged,
> too. As the -noteNumberOfRowsChanged method restores the selected row
> index set _selectedRows (and hopefully the _selectedRow index, too, 
> soon)
> from the _selectedItems instance variable, NSOutlineView's -reloadData
> has to assign a suitable value to that as well.
>
> To fix the bug, insert this at the beginning of -reloadData (before
> _items is set to nil):
>
> // We save the selection
> [_selectedItems removeAllObjects];
> int row = [_selectedRows firstIndex];
> while (row != NSNotFound)
>   {
>     if ([self itemAtRow: row])
>       {
>         [_selectedItems addObject: [self itemAtRow: row]];
>       }
>     row = [_selectedRows indexGreaterThanIndex: row];
>   }

This stuff doesn't seem to make sense to me, if the selected objects 
changes row indexes
the selected row shouldn't jump around to the new row index where the 
selected object
now is...

attached is a patch which gets rid of _selectedItems,
and implements a private method to maintain the selected row index
not the selected objects.


> BTW: The whole issue also applies to the -reloadItem:reloadChildren:
> method. There's even a FIXME describing the problem.
<NSOutlineView.diff>

NSOutlineView.diff
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