Scrollable reader for text file that does not load the entire file into memory?

[QuinnCiccoretti]

Hello open source community,
How would you display N lines of a text file, stopping at top or bottom of the file, without loading the entire file into memory? I'm trying to read a lengthy log file.
I've thought about using a line scanner on a os.File object (which implements the reader interface), and then using widget.List or widget.TextGrid.

For widget.List, I'm not sure how to avoid reading the entire file into memory to determine the "Length" of the list for the Length callback. I'm also not sure if line-by-line scanning will play nice with item pooling the docs mention.
For widget.TextGrid, there is no scrolling.

To keep things simple, let's assume we need not check for modifications to the file.
Is there a different widget you think might work better? Or a modification to those widgets that might work? 🙏 thanks

[andydotxyz]

For widget.TextGrid, there is no scrolling.

This is fixed in #5434 - it will be in v2.6.0

There is no builtin widget that will allow you to load a portion of a file without any dev work in the app.

To recommend more may require if you are looking to "head" or "tail" the file (your first sentence suggests both) and if you want to scroll it all at some point. These are all different use-cases so would probably take a different approach,

If you really want to see it all but are worried about performance I would suggest trying out the scrolling text grid which is basically the closest thing we have to a log viewer.

[QuinnCiccoretti]

Cheers andy, looks like scrolling text grid is what I want.