Add setcursor and reframe to scrolllist and flesh out il

1 files changed, 18 insertions, 0 deletions

diff --git a/tui/widget/list/scrolllist.ha b/tui/widget/list/scrolllist.ha
index 3aaad87..d08c7d7 100644
--- a/tui/widget/list/scrolllist.ha
+++ b/tui/widget/list/scrolllist.ha
@@ -115,6 +115,24 @@ export fn bottom(li: *scrolllist) void = {
 	li.frame.start = len(li.items): u16 - sz;
 };
 
+export fn setcursor(li: *scrolllist, newpos: u16) void = {
+	li.cursor = newpos;
+	reframe(li);
+};
+
+fn reframe(li: *scrolllist) void = {
+	if (li.cursor > li.frame.end) {
+		const diff = li.frame.end - li.frame.start;
+		li.frame.start = li.cursor;
+		li.frame.end = li.frame.start + diff;
+	};
+	if (li.cursor < li.frame.start) {
+		const diff = li.frame.end - li.frame.start;
+		li.frame.end = li.cursor;
+		li.frame.start = li.frame.end - diff;
+	};
+};
+
 fn stylesscrolllist(widget: *widget::widget, txt: str, idx: size) str = {
 	const list = widget: *scrolllist;
 	const idx = idx + list.frame.start;