fix: wait for updateComplete before setting positionTarget

[web-padawan]

Description

Fixes vaadin/flow-components#6368

This fixes a regression introduced by #7015 where setting positionTarget was delayed. It turns out we only need to wait for updateComplete when using Lit so that overlay rect is measured (no need to wait until vaadin-overlay-open).

With this approach, the logic setting positionTarget to undefined and removing style attribute turns out to be unnecessary and even problematic (as it's what caused blinking at the bottom of the screen), so I removed it.

Note: I couldn't find an easy approach to test this. However, existing tests for sub-menu position do cover the new code.

Type of change

• Bugfix

[DiegoCardoso]

I can see that the initial blink in the bottom right corner is gone, however, there's still one minor issue when a sub-menu is opened after another one closes:

menu-bar-blink.mp4

As seen in the recording, it briefly opens in its last position and then it moves to the right one.

[web-padawan]

As seen in the recording, it briefly opens in its last position and then it moves to the right one.

Right, thanks. I think that's what I originally attempted to prevent when converting to Lit. Will investigate it further.

[web-padawan]

@DiegoCardoso updated to use a different approach, now the flickering seems to be gone. Could you please check it?

[DiegoCardoso]

I can't see any flashing now. I checked the Lit element and also didn't see any issues there. Even after removing the await overlay.updateComplete line, but that makes some tests fail, so it could be something so quick I wasn't able to notice, so it might be better to keep it.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[vaadin-bot]

This ticket/PR has been released with Vaadin 24.5.0.alpha5 and is also targeting the upcoming stable 24.5.0 version.