Center the selected item when updating outline query

Antonio Scandurra , Max Brunsfeld , and Nathan Sobo created 4 years ago

Co-Authored-By: Max Brunsfeld <[e-mail]>
Co-Authored-By: Nathan Sobo <[e-mail]>

Change summary

crates/file_finder/src/file_finder.rs       |  9 +++-
crates/gpui/src/elements/uniform_list.rs    | 41 +++++++++++++++++-----
crates/outline/src/outline.rs               | 14 +++++--
crates/project_panel/src/project_panel.rs   |  6 +-
crates/theme_selector/src/theme_selector.rs |  6 ++-
5 files changed, 54 insertions(+), 22 deletions(-)

Detailed changes

crates/file_finder/src/file_finder.rs

@@ -353,7 +353,8 @@ impl FileFinder {
             let mat = &self.matches[selected_index];
             self.selected = Some((mat.worktree_id, mat.path.clone()));
         }
-        self.list_state.scroll_to(selected_index);
+        self.list_state
+            .scroll_to(ScrollTarget::Show(selected_index));
         cx.notify();
     }
 
@@ -364,7 +365,8 @@ impl FileFinder {
             let mat = &self.matches[selected_index];
             self.selected = Some((mat.worktree_id, mat.path.clone()));
         }
-        self.list_state.scroll_to(selected_index);
+        self.list_state
+            .scroll_to(ScrollTarget::Show(selected_index));
         cx.notify();
     }
 
@@ -415,7 +417,8 @@ impl FileFinder {
             }
             self.latest_search_query = query;
             self.latest_search_did_cancel = did_cancel;
-            self.list_state.scroll_to(self.selected_index());
+            self.list_state
+                .scroll_to(ScrollTarget::Show(self.selected_index()));
             cx.notify();
         }
     }

crates/gpui/src/elements/uniform_list.rs

@@ -14,9 +14,14 @@ use std::{cmp, ops::Range, sync::Arc};
 #[derive(Clone, Default)]
 pub struct UniformListState(Arc<Mutex<StateInner>>);
 
+pub enum ScrollTarget {
+    Show(usize),
+    Center(usize),
+}
+
 impl UniformListState {
-    pub fn scroll_to(&self, item_ix: usize) {
-        self.0.lock().scroll_to = Some(item_ix);
+    pub fn scroll_to(&self, scroll_to: ScrollTarget) {
+        self.0.lock().scroll_to = Some(scroll_to);
     }
 
     pub fn scroll_top(&self) -> f32 {
@@ -27,7 +32,7 @@ impl UniformListState {
 #[derive(Default)]
 struct StateInner {
     scroll_top: f32,
-    scroll_to: Option<usize>,
+    scroll_to: Option<ScrollTarget>,
 }
 
 pub struct LayoutState {
@@ -97,14 +102,32 @@ where
             state.scroll_top = scroll_max;
         }
 
-        if let Some(item_ix) = state.scroll_to.take() {
+        if let Some(scroll_to) = state.scroll_to.take() {
+            let item_ix;
+            let center;
+            match scroll_to {
+                ScrollTarget::Show(ix) => {
+                    item_ix = ix;
+                    center = false;
+                }
+                ScrollTarget::Center(ix) => {
+                    item_ix = ix;
+                    center = true;
+                }
+            }
+
             let item_top = self.padding_top + item_ix as f32 * item_height;
             let item_bottom = item_top + item_height;
-
-            if item_top < state.scroll_top {
-                state.scroll_top = item_top;
-            } else if item_bottom > (state.scroll_top + list_height) {
-                state.scroll_top = item_bottom - list_height;
+            if center {
+                let item_center = item_top + item_height / 2.;
+                state.scroll_top = (item_center - list_height / 2.).max(0.);
+            } else {
+                let scroll_bottom = state.scroll_top + list_height;
+                if item_top < state.scroll_top {
+                    state.scroll_top = item_top;
+                } else if item_bottom > scroll_bottom {
+                    state.scroll_top = item_bottom - list_height;
+                }
             }
         }
     }

crates/outline/src/outline.rs

@@ -187,19 +187,23 @@ impl OutlineView {
 
     fn select_prev(&mut self, _: &SelectPrev, cx: &mut ViewContext<Self>) {
         if self.selected_match_index > 0 {
-            self.select(self.selected_match_index - 1, true, cx);
+            self.select(self.selected_match_index - 1, true, false, cx);
         }
     }
 
     fn select_next(&mut self, _: &SelectNext, cx: &mut ViewContext<Self>) {
         if self.selected_match_index + 1 < self.matches.len() {
-            self.select(self.selected_match_index + 1, true, cx);
+            self.select(self.selected_match_index + 1, true, false, cx);
         }
     }
 
-    fn select(&mut self, index: usize, navigate: bool, cx: &mut ViewContext<Self>) {
+    fn select(&mut self, index: usize, navigate: bool, center: bool, cx: &mut ViewContext<Self>) {
         self.selected_match_index = index;
-        self.list_state.scroll_to(self.selected_match_index);
+        self.list_state.scroll_to(if center {
+            ScrollTarget::Center(index)
+        } else {
+            ScrollTarget::Show(index)
+        });
         if navigate {
             let selected_match = &self.matches[self.selected_match_index];
             let outline_item = &self.outline.items[selected_match.candidate_id];
@@ -319,7 +323,7 @@ impl OutlineView {
                 .unwrap_or(0);
             navigate_to_selected_index = !self.matches.is_empty();
         }
-        self.select(selected_index, navigate_to_selected_index, cx);
+        self.select(selected_index, navigate_to_selected_index, true, cx);
     }
 
     fn render_matches(&self) -> ElementBox {

crates/project_panel/src/project_panel.rs

@@ -1,8 +1,8 @@
 use gpui::{
     action,
     elements::{
-        Align, ConstrainedBox, Empty, Flex, Label, MouseEventHandler, ParentElement, Svg,
-        UniformList, UniformListState,
+        Align, ConstrainedBox, Empty, Flex, Label, MouseEventHandler, ParentElement, ScrollTarget,
+        Svg, UniformList, UniformListState,
     },
     keymap::{
         self,
@@ -278,7 +278,7 @@ impl ProjectPanel {
 
     fn autoscroll(&mut self) {
         if let Some(selection) = self.selection {
-            self.list.scroll_to(selection.index);
+            self.list.scroll_to(ScrollTarget::Show(selection.index));
         }
     }
 

crates/theme_selector/src/theme_selector.rs

@@ -140,7 +140,8 @@ impl ThemeSelector {
         if self.selected_index > 0 {
             self.selected_index -= 1;
         }
-        self.list_state.scroll_to(self.selected_index);
+        self.list_state
+            .scroll_to(ScrollTarget::Show(self.selected_index));
         cx.notify();
     }
 
@@ -148,7 +149,8 @@ impl ThemeSelector {
         if self.selected_index + 1 < self.matches.len() {
             self.selected_index += 1;
         }
-        self.list_state.scroll_to(self.selected_index);
+        self.list_state
+            .scroll_to(ScrollTarget::Show(self.selected_index));
         cx.notify();
     }