From d3cff3e9238228c98b6de09c7f6c08ffc5b1e343 Mon Sep 17 00:00:00 2001
From: yumoqing <yumoqing@gmail.com>
Date: Wed, 2 Sep 2026 11:02:51 +0800
Subject: [PATCH] =?UTF-8?q?fix(AgentIO):=20=E8=B7=9F=E6=BB=9A=E8=AF=AF?=
 =?UTF-8?q?=E5=85=B3=E6=A0=B9=E6=B2=BB=E2=80=94=E2=80=94=5Ftrack=5Ffollow?=
 =?UTF-8?q?=E6=8C=89scrollTop=E5=87=8F=E5=B0=8F=E5=88=A4=E7=94=A8=E6=88=B7?=
 =?UTF-8?q?=E4=B8=8A=E7=BF=BB?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

旧实现按gap判follow:异步widget挂载使scroll事件滞后,程序滚底后gap瞬时>80
被误判为用户上翻→follow关→第二条消息后输出不再跟滚
---
 bricks/agent.js | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/bricks/agent.js b/bricks/agent.js
index cdaaef6..cbe4b39 100644
--- a/bricks/agent.js
+++ b/bricks/agent.js
@@ -357,7 +357,20 @@ bricks.AgentIO = class extends bricks.VBox {
 	_track_follow(){
 		var e = this.msg_box && this.msg_box.dom_element;
 		if (!e) return;
-		this._follow = (e.scrollHeight - e.scrollTop - e.clientHeight) < 80;
+		var st = e.scrollTop;
+		var near = (e.scrollHeight - st - e.clientHeight) < 80;
+		if (near) {
+			// 滚回底部附近 → 恢复跟滚
+			this._follow = true;
+		} else if (this._last_st !== undefined && st < this._last_st - 5) {
+			// scrollTop 减小 = 用户真上翻 → 暂停跟滚。
+			// 程序滚底只会增大 scrollTop；异步 widget 挂载使 scroll 事件滞后时
+			// gap 会瞬时 >80，但 st 不减小——不能误判为用户上翻（2026-09-01 根因：
+			// 旧实现按 gap 判 follow，第二条消息后程序滚底被自己的 scroll 事件
+			// 误关 follow，后续输出不再跟滚）。
+			this._follow = false;
+		}
+		this._last_st = st;
 	}
 	chunk_response(mout, l){
 		l = l.trim();