Problem in detail:

When editing a cell in a tree view, the editing is canceled when one clicks on a button outside the tree view, and the entered value is discarded. One has to click in the tree view or press enter in order to save the new value. These are very limited conditions that are not straightforward for the end user. 

Consider for example a tree view in a dialog box. When one is editing a cell and one has entered the desired value, it is very natural to click immediately on the OK button without first pressing enter or clicking somewhere else. The effect is that the new value is discarded and because the dialog disappears directly, the user does not notice that the new value is not saved. This causes a lot of confusion to end users. I have to explain them over and over again that they first have to press enter.

Proposed solution:

The function gtk_cell_renderer_text_focus_out_event in gtkcellrenderertext.c should be modified. Now it just cancels editing. It should save the value in the tree model. The escape button should become the only way to cancel editing.

Thanks

Other information: