GUI设计中的tree_hierachral数据，----用于RGtk2，R中的包使用GTK

In RGtk2, we can create a treeview for a hierachral data, and there are several signals associated with this representation , We want to to "click" the item then it shows something to our user, but all signals are either "double clicked" or are for "cursor move" type, there is no signals associated for "single click". So is there anyway that we just do a single click the item then it emits signal to show something ?In RGtk2, we can create a treeview for a hierac