Fix TreeView root index.

Parent folders will now be hidden based on the root folder selection in
the GUI.

qml/ClideTreeView.qml

@@ -27,6 +27,7 @@ Rectangle {
         boundsBehavior: Flickable.StopAtBounds
         boundsMovement: Flickable.StopAtBounds
         clip: true
+        rootIndex: FileSystem.rootIndex
 
         Component.onCompleted: {
             FileSystem.setDirectory(root.rootDirectory)
@@ -122,13 +123,13 @@ Rectangle {
                     text: qsTr("Set as root index")
                     onTriggered: {
                         console.log("Setting directory: " + treeDelegate.filePath)
-                        FileSystem.setDirectory(treeDelegate.filePath)
+                        FileSystem.rootIndex = FileSystem.setDirectory(treeDelegate.filePath)
                     }
                 }
                 Action {
                     text: qsTr("Reset root index")
                     onTriggered: {
-                        FileSystem.setDirectory("")
+                        FileSystem.rootIndex = FileSystem.setDirectory(root.rootDirectory)
                     }
                 }
             }