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#PB_ListView_MultiSelect causes screen readers to repeat list items when at the beginning/end
Posted: Thu Feb 20, 2025 4:29 pm
by Quin
Steps to reproduce:
1. Start Narrator.
2. Run my below code and up/down arrow through the two lists. Notice the difference in behavior between the multiselect list and the single-select list when you're at the top/bottom of them.
Code: Select all
EnableExplicit
Define i.i
OpenWindow(0, #PB_Ignore, #PB_Ignore, 600, 400, "Test")
ListViewGadget(0, 5, 5, 250, 100)
ListViewGadget(1, 300, 5, 250, 100, #PB_ListView_MultiSelect)
For i = 0 To 10
AddGadgetItem(0, -1, "This is item number " + i)
AddGadgetItem(1, -1, "This is item number " + i)
Next
Repeat : Until WaitWindowEvent(1) = #PB_Event_CloseWindow
In my mind, the single-select list view is correct, as that's how listviews behave everywhere else in Windows, even lists that do let you select multiple items, e.g. explorer.
Re: #PB_ListView_MultiSelect causes screen readers to repeat list items when at the beginning/end
Posted: Thu Feb 20, 2025 4:31 pm
by Quin
Just tested and can confirm that it also happens with #PB_ListView_ClickSelect
Re: #PB_ListView_MultiSelect causes screen readers to repeat list items when at the beginning/end
Posted: Mon Apr 14, 2025 6:13 pm
by Fred
https://www.purebasic.fr/english/viewtopic.php?t=86350
I tried with NVDA on Windows 10 but I don't see any difference between the 2. I checked the ListIconGadget() gadget and we don't modify anything related to selection or keyboard handling, so that's wierd.
Re: #PB_ListView_MultiSelect causes screen readers to repeat list items when at the beginning/end
Posted: Mon Apr 14, 2025 7:05 pm
by Quin
Perhaps its a bug in Windows? What if you create those lists in a pure Win32 C application and then try the same thing? Eliminate the possible layer of PB's gadgets, although I don't see any logical reason they'd be causing issues.
Re: #PB_ListView_MultiSelect causes screen readers to repeat list items when at the beginning/end
Posted: Tue Apr 15, 2025 8:32 am
by Fred
May be someone else can try to reproduce it, to ensure it's not related to a specific config
Re: #PB_ListView_MultiSelect causes screen readers to repeat list items when at the beginning/end
Posted: Wed Apr 16, 2025 3:00 pm
by breeze4me
https://learn.microsoft.com/en-us/windo ... -selchange
For a multiple-selection list box, the LBN_SELCHANGE notification code is sent whenever the user presses an arrow key, even if the selection does not change.
In a multi-select listview gadget, holding down the arrow keys on the first and last item causes continuous LBN_SELCHANGE notifications, which seems to be causing the issue.
As you can see by running the code below, the same thing happens when the #PB_ListView_ClickSelect flag is set.
Code: Select all
Procedure WinCallback(hWnd, uMsg, WParam, LParam)
If uMsg = #WM_COMMAND
If (WParam >> 16) & $FFFF = #LBN_SELCHANGE
If LParam = GadgetID(0)
Debug "g0: " + GetGadgetState(0)
ElseIf LParam = GadgetID(1)
Debug "g1: " + GetGadgetState(1)
EndIf
EndIf
EndIf
ProcedureReturn #PB_ProcessPureBasicEvents
EndProcedure
Define i.i
OpenWindow(0, #PB_Ignore, #PB_Ignore, 600, 400, "Test")
SetWindowCallback(@WinCallback(), 0)
ListViewGadget(0, 5, 5, 250, 100)
ListViewGadget(1, 300, 5, 250, 100, #PB_ListView_MultiSelect)
;ListViewGadget(1, 300, 5, 250, 100, #PB_ListView_ClickSelect)
For i = 0 To 10
AddGadgetItem(0, -1, "This is item number " + i)
AddGadgetItem(1, -1, "This is item number " + i)
Next
Repeat : Until WaitWindowEvent(1) = #PB_Event_CloseWindow
Re: #PB_ListView_MultiSelect causes screen readers to repeat list items when at the beginning/end
Posted: Wed Apr 16, 2025 3:02 pm
by Quin
Iiiiinteresting, so it's not a bug, just utterly baffling behhavior on the part of Microsoft. Who's surprised?
You're a wizard, Breeze4Me