excel vba - Passing class object by 'property get' in a parent class does not affect the nested class object -

i have hierarchy of classes defined follows

cquestion:

private ptext string  private sub class_initialize() ptext = "" end sub  property let text(t string)     ptext = t end property  property text() string     text = ptext end property 

cquestionlist:

private pqlist() new cquestion private plistlen integer  private sub class_initialize()     plistlen = 0 end sub  public sub addend(q string)     plistlen = plistlen + 1     redim preserve pqlist(1 plistlen)     pqlist(plistlen).text = q end sub  public function format() string     dim integer     if plistlen = 0         formatlist = "there no questions in category" + vbnewline     else         formatlist = "questions:" + vbnewline         = 1 plistlen             formatlist = formatlist + "• " + pqlist(i).text + vbnewline         next     end if end function 

ccategory:

private pname string private pqlist new cquestionlist  private sub class_initialize()     pname = "" end sub  property questionlist() cquestionlist     set questionlist = pqlist end property  property let name(n string)     pname = n end property  property name() string     name = pname end property 

when attempt call category.questionlist.addend "question here", not throw errors. when subsequently call msgbox category.questionlist.format blank message box. not sure how ends blank, seeing format should returning text. doing wrong here? have looked @ other examples of passing class objects let , within parent class, , cannot see how doing different. suggestions?

example code:

dim c new ccategory c.questionlist.addend "a question" c.questionlist.addend "another question" msgbox c.questionlist.format 

put option explicit @ top of each module , you'll see problem immediately:

public function format() string     dim integer     if plistlen = 0         formatlist = "there no questions in category" + vbnewline            '^^^^ variable not defined.     else         formatlist = "questions:" + vbnewline         = 1 plistlen             formatlist = formatlist + "• " + pqlist(i).text + vbnewline         next     end if end function 

you either need change public function format() string public function formatlist() string or change formatlist assignments format.

i'd go formatlist naming avoid collisions format function.