add expand keybinding

gui/gui.go

@@ -23,6 +23,7 @@ func New() *Gui {
 
 func (g *Gui) Run(i interface{}) error {
 	g.Tree.UpdateView(g, i)
+	g.Tree.SetKeybindings()
 
 	grid := tview.NewGrid().
 		AddItem(g.Tree, 0, 0, 1, 1, 0, 0, true)

gui/tree.go

@@ -90,3 +90,11 @@ func (t *Tree) NewNodeWithLiteral(i interface{}) *tview.TreeNode {
 
 	return node.SetText(text)
 }
+
+func (t *Tree) SetKeybindings() {
+	t.SetSelectedFunc(func(node *tview.TreeNode) {
+		if len(node.GetChildren()) > 0 {
+			node.SetExpanded(!node.IsExpanded())
+		}
+	})
+}