disproportional vertical scroll when zoomed in

[asnav]

📝 Describe the Bug:
while zoomed in vertical scroll is disproportional, horizontal scroll works just fine which means zoom is taken into account.
i assume there is an extra pan behavior on top of the basic scroll function which makes it too fast.

📖 Library Version: 2.0.7

🚶 Steps to Reproduce:
Please follow these steps to reproduce the issue:

1. load a pdf file
2. zoom in
3. scroll up or down
4. notice that the view moves faster than your finger

🤔 Expected Behavior:
the view should move along with he pointer (your finger) at the same speed

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[mlilienberg]

When google started with instant apps i also implemented a library with a similar approach like this. We use it in production without changes since 2019. This library is published and maintained by a former colleague of mine, you find it here: https://github.com/Dmitry-Borodin/pdfview-android.

I do not want to advertise that library but maybe you can find any technics to improve this one. I was looking into an alternative that is still maintained and has a compose API, but with some weakness like the disproportional scrolling when zoomed I can not use it as a replacement.

So what is the difference? The other library uses a slightly modified clone of subsampling scale imageview to have following benefits:

• Sharp rendering in any zoom level (especially for text and vector drawings)
• Only render the visible rect, so that it can handle documents with thousands of pages without delay or memory issues
• Proportional scroll at any zoom level

Maybe it is possible to merge the concepts of those two libraries.

[Sasikumars41]

📝 Describe the Bug: while zoomed in vertical scroll is disproportional, horizontal scroll works just fine which means zoom is taken into account. i assume there is an extra pan behavior on top of the basic scroll function which makes it too fast.

📖 Library Version: 2.0.7

🚶 Steps to Reproduce: Please follow these steps to reproduce the issue:

1. load a pdf file
2. zoom in
3. scroll up or down
4. notice that the view moves faster than your finger

🤔 Expected Behavior: the view should move along with he pointer (your finger) at the same speed

Scrolling on vertical is not smooth as horizontal scroll after zoom.

[afreakyelf]

Hi, The Above issue has been fixed in new release. https://github.com/afreakyelf/Pdf-Viewer/releases/tag/v2.1.0

Please migrate to Maven central. More here: https://github.com/afreakyelf/Pdf-Viewer/releases/tag/v2.1.0

Thank you for using the library. Please reopen/raise a new issue if you still face this error.

Join our discord for more updates!

[Sasikumars41]

Hi,

Please slow down the scrolling speed of the scroll after zoom. It works fine on normal state.

[asnav]

It has indeed not been fixed.