Sets the cell renderer based on the tree_model and iter.
That is, for every attribute mapping in this, it will get a value from the set column on the
iter, and use that value to set the attribute on the cell renderer. This is used primarily by the
TreeView.
| this | |
| tree_model |
The TreeModel to to get the cell renderers attributes from. |
| iter |
The TreeIter to to get the cell renderer’s attributes from. |
| is_expander |
true, if the row has children |
| is_expanded |
true, if the row has visible children |