From 8afdc1835fa7aade5da73fa5b09a0babdf966c54 Mon Sep 17 00:00:00 2001
From: Drew Weymouth <dweymouth@gmail.com>
Date: Fri, 17 Nov 2023 20:13:29 -0800
Subject: [PATCH] use binary search to search visible slices
---
widget/list.go | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/widget/list.go b/widget/list.go
index cbde9bdb79..e300e3fc98 100644
--- a/widget/list.go
+++ b/widget/list.go
@@ -752,10 +752,20 @@ func (l *listLayout) updateSeparators() {
}
}
+// invariant: visible is in ascending order of IDs
func (l *listLayout) searchVisible(visible []itemAndID, id ListItemID) int {
- for i, v := range visible {
- if v.id == id {
- return i
+ // binary search
+ low := 0
+ high := len(visible) - 1
+ for low <= high {
+ mid := (low + high) / 2
+ if visible[mid].id == id {
+ return mid
+ }
+ if visible[mid].id > id {
+ high = mid - 1
+ } else {
+ low = mid + 1
}
}
return -1