[tree] fix scroll behavior when selecting or expanding a node

[Anasshahidd21]

What it does

Fixes: #3347, Fixes: #1593

The following commit updates the tree-widget to fix an issue when trees across the framework (ex: explorer, file dialog) are scrolled and nodes are selected which causes a jump and subsequently a poor user-experience.

The change includes updating the default value of the resize parameter in forceUpdate to false since we should only properly perform a cache clearAll only when an explicit resize has occurred.

clearAll ()
Reset cached measurements for all cells.

This method should be called when a Grid, List or Table needs to reflow content due to a resizing event for a responsive layout (eg. a window width resize may have an impact on the height of cells).

How to test

1. start the application and verify the behavior with multiple trees (ex: explorer, problems, file dialogs, siw, scm)
2. for a given tree-widget, perform a manual scroll and select a node
3. determine that the tree does not jump as reported in the issues [file-tree] Undesired scrolling issue when toggling tree node expansion state #3347 & [navigator] disturbing scroll behavior on selection #1593
4. determine that the debug console is properly rendered when resized

Review checklist

• as an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• as a reviewer, I agree to behave in accordance with the review guidelines

Signed-off-by: Anas Shahid muhammad.shahid@ericsson.com
Signed-off-by: vince-fugnitto vincent.fugnitto@ericsson.com

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Recordings:

Explorer	Debug Console

[vince-fugnitto]

I'm really happy the annoying glitch was fixed 👍
I verified using multiple trees and it all works correctly when manually scrolling and selecting a node (no more annoying jump):

• explorer
• search-in-workspace
• problems
• npm scripts

[kaiyue0329]

The changes work well 👍 ! Tested the trees in Explorer, Search-in-workspace and Problems. The scroll no longer jumps up and scrolls the selected element away.

[Anasshahidd21]

@akosyakov Thank you for your previous review. You are right, my solution was not very optimal. I have updated the code, if you can review again that would be great. As mentioned in the PR description(updated), I made use of clear as mentioned here

[vince-fugnitto]

The changes work correctly when only clearing what is necessary 👍

[akosyakov]

As mentioned in the PR description(updated), I made use of clear as mentioned here

please when you read something on the internet, think whether conditions are really applicable to our case

[vince-fugnitto]

@akosyakov the code was updated to only resize (clearAll cache) when an explicit resize occus (onResize of the widget).
Is there another case that needs to be handled? With this approach the trees are correctly selected without a jump and the debug console still wraps correctly when resized.

[akosyakov]

Is there another case that needs to be handled? With this approach the trees are correctly selected without a jump and the debug console still wraps correctly when resized.

Resizing was just my example of the case when the height of a row can change. I don't know what else can cause change of the height.

[akosyakov]

Let's try.

It would be good if someone writes down what was the root cause of the issue and why such change fixes it. I don't understand it.

[Anasshahidd21]

@kittaakos can you review this to see if it solves the issue for file-dialog for you?

[kittaakos]

can you review this to see if it solves the issue for file-dialog for you?

I have tried it and quickly compared the behavior with the master: stunning. It works great, thank you for the fix!