From 6af10978aa5a4aaf1f596c54c4c5ef3373bec905 Mon Sep 17 00:00:00 2001 From: Allan Wang Date: Sat, 3 Oct 2020 21:27:10 -0700 Subject: Add back scroll position after height change --- app/src/web/ts/auto_resize_textarea.ts | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'app/src/web/ts') diff --git a/app/src/web/ts/auto_resize_textarea.ts b/app/src/web/ts/auto_resize_textarea.ts index 1f1b3613..c71a75a1 100644 --- a/app/src/web/ts/auto_resize_textarea.ts +++ b/app/src/web/ts/auto_resize_textarea.ts @@ -12,8 +12,19 @@ // If no height is defined, have min bound to current height; // otherwise we will allow for height decreases in case user deletes text const minHeight = parseInt(el.getAttribute(dataAttribute) ?? '0'); + + // Save scroll position prior to height update + // See https://stackoverflow.com/a/18262927/4407321 + const scrollLeft = window.pageXOffset || + (document.documentElement || document.body.parentNode || document.body).scrollLeft; + const scrollTop = window.pageYOffset || + (document.documentElement || document.body.parentNode || document.body).scrollTop; + el.style.height = 'inherit'; el.style.height = `${Math.max(el.scrollHeight, minHeight)}px`; + + // Go to original scroll position + window.scrollTo(scrollLeft, scrollTop); }; function _frostExpandAll() { textareas.forEach(_frostAutoExpand); -- cgit v1.2.3