Execute via Debug Console:
[] spawn
{
disableSerialization;
_CT_TREE = findDisplay 46 ctrlCreate ["RscTree", -1];
_CT_TREE ctrlSetPosition [0,0,0.3,1];
_CT_TREE ctrlCommit 0;
_CT_TREE tvAdd [[],"Parent_A"];
_CT_TREE tvAdd [[0],"Child_A"];
_CT_TREE tvAdd [[0],"Child_B"];
_CT_TREE tvAdd [[0],"Child_C"];
_CT_TREE tvExpand [0];
sleep 1;
for "_i" from 0 to 2 do {
hint format ["Selecting Child %1",_i];
_CT_TREE tvSetCurSel [0,_i];
sleep 1;
};
sleep 1;
hint "DESELECT ALL";
_CT_TREE tvSetCurSel [-1];
};