Scroll with ctrl+e and ctrl+d

src/ui/chat/tree/cursor.rs

@@ -223,6 +223,23 @@ impl<M: Msg, S: MsgStore<M>> InnerTreeViewState<M, S> {
         // Not really necessary; only here for consistency with other methods
         self.make_cursor_visible = true;
     }
+
+    pub async fn scroll_up(&mut self, amount: i32) {
+        self.scroll += amount;
+
+        if let Cursor::Bottom = self.cursor {
+            // Move cursor to bottommost message, if it exists
+            if let Some(mut id) = self.store.last_tree_id().await {
+                let tree = self.store.tree(&id).await;
+                while Self::find_last_child(&tree, &mut id) {}
+                self.cursor = Cursor::Msg(id);
+            }
+        }
+    }
+
+    pub fn scroll_down(&mut self, amount: i32) {
+        self.scroll -= amount;
+    }
 }
 
 /*