Bending Pattern Swatches with Objects & Paths

That's exactly what I was trying to do! Thank you so much. Before I mark this as the answer, how do I edit how often it repeats so it smoothly transitions like yours does? I tried what you suggested and there are too few copies in mine

This is helpful, but the whole point is I want to be able to manipulate the pattern with minimal distortion on a spline so I can make more complicated curving patterns.

The Threads login screen is a pretty good example of the overall effect I want to achieve.

Like this with effects: 

Hi Doug,

Thanks for your interest. I want the pattern to follow a curve without distorting. I realize some distortion will occur due to the curve, but my goal is to make it as minimal as possible.

While using a pattern brush it typically is pretty good except for on the more curved segments such as the elbows.

For example, if I had a four-line pattern solely consisting of filled black lines that were alternating with filled white lines of the same width, I want to be able to curve them to do things like in the photo below:

(Photo from Shutterstock)

My initial goal was to be able to do this with lines filled with the pattern but I'm not sure if that's possible.

I might try getting the same effect using some of the Envelope Distort tools but I fear they'll distort or have the results same as the things I've tried previously that haven't worked.