The CreateTree creates a Tree control if it is called for the first time ( changes the face's Type property to exFaceTree), and retrieve the FaceTree object, for the next calls. The FaceTree property retrieves FaceTree object, if the face's Type property is exFaceTree, else it returns nothing. The InitFaceTree / InitFaceContent event occurs once the face's Type property has been changed to exFaceTree, or calling the CreateTree method for the first time. You can use the InitFaceTree event to initialize all faces of Tree type. The Visible property specifies whether the face's content is visible or hidden. The Enabled property enables or disables the face. Use the RelativeMargins / Margins property to specify the margins of the face's content relative to its face. 

A face that contains a Tree control may fire any of the following events ( CreateTree, Type on exFaceTree ): 

• InitFaceTree event ( InitFaceContent event )
• FaceTreeButtonClick event
• FaceTreeExpandItem event
• FaceTreeSelectionChanged event
• FaceTreeStateChanged event
• FaceTreeValueChanged event