Glitch | gathering players of Glitch , by Tiny Speck

So I have a side navigation that has a sub-menu in some of the list, and I'm trying to display the sub-menu only when it's clicked.

Here is the HTML

Why I can't dynamically change content in VStack if I don't have a lot objects in ScrollView? What is surprising, if there are a lot of objects, then everything changes beautifully, but if there are few, then the scroll only works down (because of this, there may be glitches when trying to scroll up)

My code:

I'm currently on debug mode and run my app on my device.

I'm using sign_in_with apple and this code

I would like to be able to robustly stop a video when the video arrives on some specified frames in order to do oral presentations based on videos made with Blender, Manim...

I'm aware of this question, but the problem is that the video does not stops exactly at the good frame. Sometimes it continues forward for one frame and when I force it to come back to the initial frame we see the video going backward, which is weird. Even worse, if the next frame is completely different (different background...) this will be very visible.

To illustrate my issues, I created a demo project here (just click "next" and see that when the video stops, sometimes it goes backward). The full code is here.

The important part of the code I'm using is:

The Problem

I have locally-generated data that I need to display in a RecyclerView. I tried to use a custom PagingSource with PagingDataAdapter to reduce the amount of data in memory, but I get visual effects when I invalidate the data, for example if I insert or delete one item:

• when the visible items belong to 2 different "pages", many unchanged items flash as if they had been modified
• if all the visible items belong to the same page, everything is fine. Only the inserted / deleted item shows an animation.

I took an example application referenced by Google's doc (PagingSample) to test the concept. The original with Room does not show artefacts, but my modified version with custom PagingSource does.

The code generated and used by Room is too complicated to see any difference that would explain the issue.

My data must be locally-generated, I can't use Room as a work-around to display them.

My question

How can I properly define a PagingSource for my local data, and use it with PagingDataAdapter without visual glitches?

Optionally, how can I know when data is discarded (so I can discard my local data as well)?

Code excerpts and details

The full example project is hosted here: https://github.com/blueglyph/PagingSampleModified

Here is the data:

I am currently working on a project to download .mp4 files from links from a text document, and it works with this code

I got half-way through what I wanted in the representation of physics vector fields in 2D with p5js here. The other half is to get random particles to dynamically follow the forces of the vector field, and I am having a lot of problems with it. I have tried multiple things to take into account the wrap-around of the particles, as well as the fact that I am translating the origin of the plot to the center of the canvas. However, the particles seem minimally affected by the individual vectors in the field, and ultimately march along the x axis with slight bumpiness.

The fact that I am completely new at JS doesn't help splice all these elements from several presentations available online, and I would appreciate any advise as to what may be going wrong, and where I should focus on.

Here is what I have so far: a file sketch.js corresponding to my own answer quoted above:

(Solution has been found, please avoid reading on.)

I am creating a pixel art editor for Android, and as for all pixel art editors, a paint bucket (fill tool) is a must need.

To do this, I did some research on flood fill algorithms online.

I stumbled across the following video which explained how to implement an iterative flood fill algorithm in your code. The code used in the video was JavaScript, but I was easily able to convert the code from the video to Kotlin:

https://www.youtube.com/watch?v=5Bochyn8MMI&t=72s&ab_channel=crayoncode

Here is an excerpt of the JavaScript code from the video:

Converted code:

I'm setting up a view where table rows can be dragged to another table inside another div. While dragging a row, I highlight the droppable area by changing the background color. However, when dragging an element over elements within the droppable div, the background color glitches in and out.

I've reproduced it in JSFiddle (link) with the following code:

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