Learn ttreeview [14]-stateindex (status icon) and overlayindex (overlay icon)

Add the following icon to imagelist1:

Tips about overlayindex:
Before specifying an overlayindex for a node, use imagelist1.overlay to specify the available overlayindex number.

Test:

Unit unit1; interfaceuses windows, messages, sysutils, variants, classes, graphics, controls, forms, dialogs, modules, imglist, stdctrls, extctrls; Type tform1 = Class (tform) treeview1: metadata; identifier: timagelist; edit1: tedit; edit2: tedit; label1: tlabel; label2: tlabel; button1: tbutton; Procedure formcreate (Sender: tobject); Procedure edit1keyup: tobject; var key: word; shift: tshiftstate); Procedure edit2keyup (Sender: tobject; var key: word; shift: tshiftstate); Procedure treeview1change (Sender: tobject; node: ttreenode); Procedure button1click (Sender: tobject); end; var form1: tform1; implementation {$ R *. DFM} procedure tform1.formcreate (Sender: tobject); var node: ttreenode; begin {specify imagelist} treeview1.images: = imagelist1; inline: = imagelist1; {set overlayindex, up to 4} imagelist1.overlay (); {parameter 1 is the serial number in imagelist; parameter 2 is the optional overlayindex} imagelist1.overlay (); imagelist1.overlay (); imagelist1.overlay ); label1.caption: = 'stateindex: '; label2.caption: = 'overlayindex:'; edit1.text: = '-1'; edit2.text: ='-1'; button1.caption: = 'initialization '; {fill treeview1} with treeview1 do begin align: = alleft; items. add (nil, 'aaa'); items. add (nil, 'bbb '); items. add (nil, 'ccc '); items. add (nil, 'ddd '); items. add (nil, 'Eee '); items. addchild (items [4], '20140901'); items. addchild (items [4], '20140901'); items. addchild (items [4], '20140901'); items. addchild (items [4], '20140901'); end; {specify the icon status} For node in treeview1.items do begin node. imageindex: = 0; {the default icon is 0th} node. selectedindex: = 1; {the selected icon is 1st} node. stateindex: =-1; {status icon none} end; {edit1 control stateindex} procedure tform1.edit1keyup (Sender: tobject; var key: word; shift: tshiftstate ); vaR C: Char; Edit: tedit; begin EDIT: = tedit (sender); C: = CHR (key); if C in ['0 '.. '6'] Then edit. text: = C else edit. text: = '-1'; {character limit} treeview1.selected. stateindex: = strtoint (edit. text); {act on Treeview} end; {edit2 controls overlayindex} procedure tform1.edit2keyup (Sender: tobject; var key: word; shift: tshiftstate); var C: Char; Edit: tedit; begin EDIT: = tedit (sender); C: = CHR (key); if C in ['0 '.. '3'] Then edit. text: = C else edit. text: = '-1'; {character limit} treeview1.selected. overlayindex: = strtoint (edit. text); {act on Treeview} end; Procedure tform1.treeview1change (Sender: tobject; node: ttreenode); begin edit1.text: = inttostr (node. stateindex); edit2.text: = inttostr (node. overlayindex); end; Procedure tform1.button1click (Sender: tobject); begin treeview1.items. clear; formcreate (NiL); end.