pascalscript - Uncheck a task checkbox at setup initialisation -

in inno setup script there's task may used under conditions determined code. in no other conditions task should executed. in fact entire tasks page skipped then. unfortunately task selection remembered inno setup , restored on every following update setup, if page isn't visible @ all.

i need uncheck task @ every setup initialisation in order forget last selected state. can't work. here's latest try:

[tasks] name: deleteconfig; description: "{cm:task_deleteconfig}"; flags: unchecked #define task_deleteconfig_index 0  [installdelete] ; delete user configuration files if task selected type: files; name: "{userappdata}\...\app.conf"; tasks: deleteconfig  [code] var     isdowngradesetup: boolean;  function initializesetup: boolean; begin     // more code not shown here, following may set under conditions     isdowngradesetup := true; end;  procedure initializewizard; begin     // clear possibly remembered value previous downgrade install     wizardform.taskslist.checked[{#task_deleteconfig_index}] := false; end;  function shouldskippage(pageid: integer): boolean; begin     // make upgrade install quicker     result := ((pageid = wpselecttasks) or ((pageid = wpready) , (getarraylength(products) = 0))) , previnstallexists; end;  procedure curpagechanged(curpageid: integer); begin     if curpageid = wpwelcome     begin         if previnstallexists         begin             // change "next" button "upgrade" on first page, because won't ask more             wizardform.nextbutton.caption := expandconstant('{cm:upgrade}');             wizardform.finishedheadinglabel.caption := expandconstant('{cm:updatedheadinglabel}');         end;     end;      if curpageid = wpselecttasks     begin         if isdowngradesetup         begin             // pre-select task delete existing configuration on downgrading (user can deselect again)             // (use zero-based index of rows in tasks list gui)             // source: http://stackoverflow.com/a/10490352/143684             wizardform.taskslist.checked[{#task_deleteconfig_index}] := true;         end;     end; end; 

this gives me a

runtime error (at 85:77): list index out of bounds (0).

i don't know "85:77" supposed recent changes can quoted code above.

i first had in initializesetup function didn't work either.

where should put code works , finds initialised tasks list? tasks page may not shown think it's late wait page become visible. in fact code used there , wasn't called when page skipped.

i not understand, why need reset task. have impression have conditional skip of task implemented incorrectly.

it's guess, assume skip task page using shouldskippage. task stays checked, if enabled in previous installation.

do not use shouldskippage this, use check parameter instead. if there's single task conditionally disabled using check parameter, whole task page gets skipped.

[tasks] name: deleteconfig; description: "{cm:task_deleteconfig}"; flags: unchecked; \   check: usedeleteconfig  [code]  function usedeleteconfig: boolean; begin   result := isdowngradesetup; end; 

---

to answer actual question, can this:

procedure curpagechanged(curpageid: integer); begin   if curpageid = wpready   begin     if previnstallexists     begin       wizardform.taskslist.checked[0] := false;     end;   end; end;  function updatereadymemo(   space, newline, memouserinfoinfo, memodirinfo, memotypeinfo, memocomponentsinfo,   memogroupinfo, memotasksinfo: string): string; begin   if previnstallexists   begin     memotasksinfo := '';   end; end; 

though again, not think, solution.

or easier, use useprevioustasks:

[setup] useprevioustasks=no 

or using checkedonce flag:

[tasks] name: deleteconfig; description: "{cm:task_deleteconfig}"; flags: unchecked checkedonce