From 6dd187ff0822230f084e43636b1aabeb1baf06f6 Mon Sep 17 00:00:00 2001
From: Héctor Ramón Jiménez <hector0193@gmail.com>
Date: Thu, 10 Mar 2022 19:25:57 +0700
Subject: Implement `pure` version of `PaneGrid` widget

---
 pure/src/widget/tree.rs | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

(limited to 'pure/src/widget/tree.rs')

diff --git a/pure/src/widget/tree.rs b/pure/src/widget/tree.rs
index 33f5693a..3fcf0922 100644
--- a/pure/src/widget/tree.rs
+++ b/pure/src/widget/tree.rs
@@ -41,6 +41,19 @@ impl Tree {
     pub fn diff_children<Message, Renderer>(
         &mut self,
         new_children: &[Element<'_, Message, Renderer>],
+    ) {
+        self.diff_children_custom(
+            new_children,
+            |new, child_state| child_state.diff(new),
+            Self::new,
+        )
+    }
+
+    pub fn diff_children_custom<T>(
+        &mut self,
+        new_children: &[T],
+        diff: impl Fn(&T, &mut Tree),
+        new_state: impl Fn(&T) -> Self,
     ) {
         if self.children.len() > new_children.len() {
             self.children.truncate(new_children.len());
@@ -49,12 +62,12 @@ impl Tree {
         for (child_state, new) in
             self.children.iter_mut().zip(new_children.iter())
         {
-            child_state.diff(new);
+            diff(new, child_state);
         }
 
         if self.children.len() < new_children.len() {
             self.children.extend(
-                new_children[self.children.len()..].iter().map(Self::new),
+                new_children[self.children.len()..].iter().map(new_state),
             );
         }
     }
-- 
cgit