事实证明，围绕 estimatedRowHeight 和 reloadRows的行为很奇怪，或者至少我不明白>;解决方案，通过一个切线相关的 SO 问题，是在行高可用时缓存行高，如果在 heightForRow 中可用，则返回该行高.

Turns out there's weird, or at least I don't understand it, behavior around estimatedRowHeight and reloadRows; solution, via a tangentially related SO question, was to cache the row heights as they become available and return that if available in heightForRow.

我猜它不会在重新加载时重新计算高度或其他东西?真的不明白具体为什么会这样，但我很高兴它确实如此！

I guess it doesn't recalculate the heights, or something, on a reload? Really don't understand specifically WHY this works, but I'm happy it does!