Bug In Colintree Scroll Handler Extension

So I seen this bug in Vertical Scroll Handler so to reproduce this you need to hide title bar on screen 1 and take a Vertical Scroll Arrangement with fill parent height and width then on screen initialize register vertical scroll arrangement then take label and type some random big text so that you can scroll vertical scroll arrangement that set all done now scroll that vertical scroll arrangement with two fingers until the app crashes, I have tested this bug on Android 9, Android 10, Android 12.
I have also reported to colintree on mail but no reply till now.

I would like to know if that can be fixed by someone in community here?

Here is the crash log:

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I changed the category. The bugs category is for bugs inside App Inventor and it is not clear yet if that is the case or that the extension is at fault.

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If I remember correctly, this is a well known bug in the ColinTreeScrollHandler extension.

Why not use the extension I suggested to you?


Then tell me what to put inside hScrollView?
Note: Don't tell me that you use kodular go and ask in kodular community, I don't use kodular my primary builder is app inventor and this is the screenshot from their community.

You put true if you want hScrollView and false if you want vScrollView. The same approach applies in other similar blocks.

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Because of this only I don't select solution in my threads, what's the reason of closing why you promote user to make duplicate threads?
Sorry If I said something wrong. Please do let me know the reason behind closing?

Marking solution doesn't close a topic. A topic is closed automatically 7 days after the last reply


This happens automatically in Discourse (the community software) when a solution is checked.

In this instance, it is correct as a solution was found, you chose to raise another,separate issue in the same topic, you should have started a new topic, which would not be a duplicate.

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@TIMAI2 I am getting this in this extension:
Attempt to invoke virtual method 'int android.widget.ScrollView.getChildCount()' on a null object reference

Do you have screen scrolling turned on? Do you have a scrolling arrangement inside another scrolling arrangement? If neither of these, then please show your relevant blocks and designer setup.




This extensions seems completely useless it can't even scroll:

Edit: Sorry I messed up with my blocks it works fine.

If you used the extension correctly.....

You want to scroll vertically (hScrollView = false), but you have set the ScrollBy to pX 200 (scroll horizontally by 200)

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yes got it but what about this:

Be a little more cautious and considerate when you are having issues


as previously requested

Sunny is giving max scroll position = 15948
While Colintree is giving max scroll position = 15703

and it's causing me lot of problems in taking out the percentage.

Oh finally it was all about companion when I exported test apk both are returing same values and also now I restarted companion so it's also same.

After a lot of hard work I guarantee this block is broken
it returns different value than full scrolled get scroll y

I have deselected the solution because this extension is buggy so I want something else that can solve my problem.

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