Tutorial
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Tree Selections
The TreeSelection object is a helper object to
manage the selection for a TreeView widget. The TreeSelection object is
automatically created when a new TreeView widget is created, and cannot
exist independently of this widget. The primary reason the
TreeSelection
object exists is for cleanliness of code and API. That is, there is no
conceptual reason all these functions could not be methods on the
TreeView widget instead of a separate method.
The TreeSelection object can be retrieved from a TreeView by calling
the following method:
Gtk::TreeSelection*
get_selection() const;
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It can be manipulated to check the selection
status of the tree, as well as select and deselect individual rows.
Selection is done completely view side. As a result, multiple views of
the same model can have completely different selections. Additionally,
you cannot change the selection of a row on the model that is not
currently displayed by the view without expanding its parents first.
One of the important things to remember when monitoring the selection
of a view is that the changed signal is mostly a hint. That
is,
it may only emit one signal when a range of rows is selected.
Additionally, it may on occasion emit a changed signal when
nothing has happened (mostly as a result of programmers calling
select_row on an already selected row).