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. 

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