Listbox: Unexpected behaviour of Page Up/Down + infinite loop

[ramires83]

Describe the bug

Page Up behaves as Page Down
Page Down key press causes infinite loop

Environment

SPA Angular web app
Windows environment

Reproducer

No response

Angular version

16.2.9

PrimeNG version

16.9.4-lts

Build / Runtime

Angular CLI App

Language

TypeScript

Node version (for AoT issues node --version)

18.17.0

Browser(s)

Chrome 121.0.6167.85 (Official Build) (64-bit)

Steps to reproduce the behavior

1. Enable checkboxes (using checkbox=true), the filter input (filter=true) and the "Show all" option (showToggleAll=true).
2. Click one of the items in the list to bring keyboard focus to the UL element (.p-listbox-list).
3. Press the Page Down key.
   Expected behaviour: List scrolls down
   Actual behaviour: nothing happens
4. Press the Page Up key.
   Expected behaviour: No action as the list is already scrolled up
   Actual behaviour: List scrolls down
5. Press the Page Up key again.
   Expected behaviour: List scrolls up
   Actual behaviour: nothing happens
6. Press the Page Down key again
   Expected behaviour: nothing happens as the list is already scrolled down
   Actual behaviour: Control enters an infinite loop and becomes unresponsive

Expected behavior

Page Down scrolls the list down
Page Up scrolls the list up
Control remains responsive

[cetincakiroglu]

Hi,

I've checked in both 17.7.0 and 16.9.5-lts versions and couldn't detect the issue. Could you please share a stackblitz example so we can identify the issue clearly?

See the examples:
v17.7.0: https://stackblitz.com/edit/dmauwb?file=src%2Fapp%2Fdemo%2Flistbox-basic-demo.html,src%2Fapp%2Fdemo%2Flistbox-basic-demo.ts

v16.9.5-lts: https://stackblitz.com/edit/rxs1db?file=src%2Fapp%2Fdemo%2Flistbox-virtual-scroll-demo.ts,src%2Fapp%2Fdemo%2Flistbox-virtual-scroll-demo.html

While waiting for the example, I'm moving the issue to the next milestone.

[cetincakiroglu]

Closing the issue due to inactivity. Feel free to open a new issue with the reproducer.