ScrollHandler: Handle the scroll of Scroll Views

1. Introduction

ScrollHandler extension can be used to handle the scroll and properties of scroll views.
Latest Version: 1.4
Released: August 14, 2020
Last Updated: June 27, 2023

2. Blocks

image

3. Documentation and Download

Please visit my website for documentation and downloading aix file.

Alternatively you can check Github Repo.

Thank you.

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MIT can redistribute ScrollHandler extension.

I, vknow360 aka Sunny Gupta, attest that I am the author of ScrollHandler extension, grant that the extension included in this project is free and that MIT has a non-exclusive irrevocable license to republish the extension as part of the project file for the purposes of the MIT App Inventor Appathon 2023.

niceee

A demo aia.would be very useful

Is there something specific you want to know about?
Btw, extension has been up for a long time. You can find all discussions here.

Hi, I have some inquiries. I am a bit confused about what is positive or negative. Does "scrolling down from the first to the last item" mean positive px? Also, what does "direction" mean? Can I have some examples of the values? For vfullscroll, no matter I enter 1 or -1 for the direction, the vfullscroll scrolls to the first item.

One more thing - I am trying to use this extension to cancel out the effect on the scroll arrangement when I show or hide the keyboard. Instead of doing from this:
image
to this:
image
I want it to be to this:
image
Is there any code to fix this? Thank you so much for your help <333

Try

  1. Include some extra empty lines below the last item, so that the scroll handler can scroll you down further

or

  1. Resize the container so that it is "above" the keyboard, then scroll to the end

I mean I don't know how to trigger the scroll event when keyboard shows and hides, nor do I know how to calculate the magnitude of the scrolling (not just scroll to the bottom every time, item 10 is not necessarily the last item, but to the original position). Also I don't even quite know how to scroll to the bottom as I am confused about what to input for the direction

The keyboard will normally show when a textbox gets focus. use that event.

read documentation for the extension to understand what is needed to scroll to the end of an arrangement.

Up --> 33
Down --> 130
Right --> 66
Left --> 17

Hi can I pm you? I want to send the apk file to you so you can help see what the problem is.
I am creating a sort of chat function. I want that every time I send a new message or when there is a new message, the scroll arrangement automatically scrolls to the bottom using the scrollhandler extension. All the items in the scroll arrangement are made using dynamic components. I added vfullscroll: 130 under the create component script to do that. However, every time it vfullscrolls, it scrolls to the second last item, like the new dynamic component item is created after the scrolling. How should I fix it?

Use SmoothScrollTo block with sX = 0 , sY = VMaxScroll and hScrollView = false

still it scrolls to the second last item, as if the scrolling happens before a new component is added

It is obvious that you have to scroll after adding new component :slightly_smiling_face:

Yea that's what I did in the script, but it seems like when the vfullscroll occurred, it scrolls to the second last item which looks like it occurred before a new item is added

can I pm you so I can show you the app and you can see what I mean

Sure, you can PM me.

did you read the pm

13 posts were split to a new topic: Scroll by 4, Keeping Alignment

A workaround that works for me is this:

where 50 is the height of the created component (it can be larger than that...)

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