Binding value for NSTableView, but tooltip gets set as well

I've set up an NSTableView in Interface Builder to be populated from an NSArray. Each value of the array represents one row in the table. The value is bound correctly, but as a side effect, the table cell's tooltip is set to the string representation of the bound object.

In my case, the NSArray contains NSDictionary objects and the开发者_如何学Go tooltip looks like it could be the [... description] output of that dictionary. Very ugly...

I don't want the tooltip to be set at all. I have other tables that have plain NSString values bound to them and they don't have a tooltip set automatically. Is there some Interface Builder magic going on? I tried to start with a blank project - same problem.

I should add that the table cell is a custom implementation of NSTextFieldCell that uses an NSButtonCell instance to draw an image and a label into the table. The values are retrieved from the dictionary bound as value.

Why is the tooltip set when I only bind the "value" attribute?

Thanks in advance!

Fixed. Here's what happened:

• I used a custom NSTextFieldCell to draw the table cell
• The value was bound do an NSDictionary instance
• The actual cell value was magiaclly set to the string representation of the dictionary. It was not visible, because I used a custom cell.

NSTableView can draw a special tooltip-like window and show the cell's contents if that does not fit into the cell.

• For my custom cell that was the case.

Disabling this can be done by implementing the NSTableViewDelegate method:

- (BOOL)tableView:(NSTableView *)tableView 
    shouldShowCellExpansionForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger)row {

 return NO;

}