vba - Passing a parameter to an event handler procedure -

i generating scripting dictionary using 1 button on userform, using populate listbox, , need use same dictionary using second button on form. have declared dictionary either using binding so:

dim isindict new scripting.dictionary 

or late binding so

dim isindict object ... set isindict = createobject("scripting.dictionary") 

when try pass dictionary other button so:

private sub okbutton_click(isindict scripting.dictionary) 'if binding private sub okbutton_click(isindict object) 'if late binding 

i following error: "procedure declaration not match description of event or procedure having same name" on line.

any ideas i'm doing wrong?

an event handler has specific signature, owned specific interface: can't change signature, otherwise member won't match interface-defined signature , won't compile - you've observed.

why that?

say have commandbutton class, handles native win32 messages , dispatches them - might this:

public event click()  private sub handlenativewin32click()     raiseevent click end sub 

now somewhere else in code, want use class , handle click event:

private withevents mybutton commandbutton  private sub mybutton_click()     'button clicked end sub 

notice handler method named [eventsource]_[eventname] - that's hard-wired in vba, , can't change that. , if try make interface public members have underscores in names, you'll run problems. that's why pascalcase (without underscores) no matter in standard libraries.

so compiler knows you're handling mybutton.click event, because there's method named mybutton_click. looks @ parameters - if there's mismatch, wrong: that parameter isn't on interface, how event provider going supply parameter?. throws compile-time error, telling you need either make signature match, or rename procedure doesn't it's handling mybutton.click anymore.

when drop control onto form, you're getting public withevents button1 commandbutton module-level variable, free: that's how can use button1 in code refer specific button, , how click handler procedure named button1_click. note if rename button not handler, procedure no longer handle button's click event. can use rubberduck's refactor/rename tool on form designer correctly rename control without breaking code.

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variables in vba can in 1 of 3 scopes: global, module, or procedure level.

when do:

sub dosomething()     dim foo end sub 

you're declaring local-scope variable.

every module has declarations section @ top, can declare module-scope variables (and other things).

option explicit private foo  sub dosomething() end sub 

here foo module-scope variable: every single procedure in module can access - read , write.

so if have data want pass between procedures , can't alter signatures, next best option declare module-scope variable.

[ignores global scope on purpose]

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about as new - consider this:

public sub test()     dim foo collection     set foo = new collection     set foo = nothing     foo.add 42     debug.print foo.count end sub 

this code blows run-time error 91 "object variable not set", because when foo.add executes, foo's reference nothing, means there's no valid object pointer work with. consider this:

public sub test()     dim foo new collection     set foo = nothing     foo.add 42     debug.print foo.count end sub 

this code outputs 1, because as new keeps object alive in weird, unintuitive , confusing way. avoid as new possible.