fix(tabs): responsive resize cursor to match selected tab

.changeset/serious-eels-stare.md

@@ -0,0 +1,6 @@
+---
+"@heroui/tabs": patch
+"@heroui/theme": patch
+---
+
+responsive tab cursor

packages/components/tabs/src/tabs.tsx

@@ -1,7 +1,7 @@
 import type {ForwardedRef, ReactElement} from "react";
 import type {UseTabsProps} from "./use-tabs";
 
-import {useRef, useMemo} from "react";
+import {useEffect, useCallback, useRef, useMemo} from "react";
 import {forwardRef} from "@heroui/system";
 
 import {useTabs} from "./use-tabs";
@@ -44,74 +44,81 @@ const Tabs = forwardRef(function Tabs<T extends object>(
     <Tab key={item.key} item={item} {...tabsProps} {...item.props} />
   ));
 
+  const cursorRef = useRef<HTMLSpanElement | null>(null);
   const selectedItem = state.selectedItem;
   const selectedKey = selectedItem?.key;
-  const prevSelectedKey = useRef<typeof selectedKey>(undefined);
-  const prevVariant = useRef(props?.variant);
   const variant = props?.variant;
   const isVertical = props?.isVertical;
 
-  const getCursorStyles = (tabRect: DOMRect, relativeLeft: number, relativeTop: number) => {
-    const baseStyles = {
-      left: `${relativeLeft}px`,
-      width: `${tabRect.width}px`,
-    };
+  const getCursorStyles = useCallback(
+    (tabRect: DOMRect) => {
+      if (variant === "underlined") {
+        return {
+          left: `${tabRect.left + tabRect.width * 0.1}px`,
+          top: `${tabRect.top + tabRect.height - 2}px`,
+          width: `${tabRect.width * 0.8}px`,
+          height: "",
+        };
+      }
 
-    if (variant === "underlined") {
       return {
-        left: `${relativeLeft + tabRect.width * 0.1}px`,
-        top: `${relativeTop + tabRect.height - 2}px`,
-        width: `${tabRect.width * 0.8}px`,
-        height: "",
+        left: `${tabRect.left}px`,
+        top: `${tabRect.top}px`,
+        width: `${tabRect.width}px`,
+        height: `${tabRect.height}px`,
       };
-    }
+    },
+    [variant],
+  );
 
-    return {
-      ...baseStyles,
-      top: `${relativeTop}px`,
-      height: `${tabRect.height}px`,
-    };
-  };
+  const updateCursorPosition = useCallback(
+    (entries: ResizeObserverEntry[]) => {
+      if (!cursorRef.current) return;
 
-  const updateCursorPosition = (node: HTMLSpanElement, selectedTab: HTMLElement) => {
-    const tabRect = {
-      width: selectedTab.offsetWidth,
-      height: selectedTab.offsetHeight,
-    } as DOMRect;
+      const contentRect = entries[0].contentRect;
 
-    const styles = getCursorStyles(tabRect, selectedTab.offsetLeft, selectedTab.offsetTop);
+      // check if rendered
+      if (contentRect.width === 0 && contentRect.height === 0) return;
 
-    node.style.left = styles.left;
-    node.style.top = styles.top;
-    node.style.width = styles.width;
-    node.style.height = styles.height;
-  };
+      const selectedTab = entries[0].target as HTMLElement;
+      const tabRect = {
+        width: selectedTab.offsetWidth,
+        height: selectedTab.offsetHeight,
+        left: selectedTab.offsetLeft,
+        top: selectedTab.offsetTop,
+      } as DOMRect;
 
-  const handleCursorRef = (node: HTMLSpanElement | null) => {
-    if (!node) return;
+      const styles = getCursorStyles(tabRect);
 
-    const selectedTab = domRef.current?.querySelector(`[data-key="${selectedKey}"]`) as HTMLElement;
+      cursorRef.current.style.left = styles.left;
+      cursorRef.current.style.top = styles.top;
+      cursorRef.current.style.width = styles.width;
+      cursorRef.current.style.height = styles.height;
 
-    if (!selectedTab || !domRef.current) return;
+      requestAnimationFrame(() => cursorRef.current?.setAttribute("data-initialized", "true"));
+    },
+    [getCursorStyles],
+  );
 
-    const shouldDisableTransition =
-      prevSelectedKey.current === undefined || prevVariant.current !== variant;
+  useEffect(() => {
+    const selectedTab = domRef.current?.querySelector(`[data-key="${selectedKey}"]`);
 
-    node.style.transition = shouldDisableTransition ? "none" : "";
+    if (!selectedTab) return;
 
-    prevSelectedKey.current = selectedKey;
-    prevVariant.current = variant;
+    const observer = new ResizeObserver(updateCursorPosition);
 
-    updateCursorPosition(node, selectedTab);
-  };
+    observer.observe(selectedTab);
+
+    return () => observer.disconnect();
+  }, [domRef, selectedKey, updateCursorPosition]);
 
   const renderTabs = useMemo(
     () => (
       <>
         <div {...getBaseProps()}>
           <Component {...getTabListProps()}>
             {!values.disableAnimation && !values.disableCursorAnimation && selectedKey != null && (
-              <span {...getTabCursorProps()} ref={handleCursorRef} />
+              <span {...getTabCursorProps()} ref={cursorRef} />
             )}
             {tabs}
           </Component>
@@ -145,6 +152,7 @@ const Tabs = forwardRef(function Tabs<T extends object>(
       values.state,
       destroyInactiveTabPanel,
       domRef,
+      cursorRef,
       variant,
       isVertical,
     ],

packages/core/theme/src/components/tabs.ts

@@ -69,9 +69,11 @@ const tabs = tv({
       "z-0",
       "bg-white",
       "will-change-[transform,width,height]",
-      "transition-[left,top,width,height]",
-      "duration-250",
-      "ease-out",
+      "invisible",
+      "data-[initialized=true]:visible",
+      "data-[initialized=true]:transition-[left,top,width,height]",
+      "data-[initialized=true]:duration-250",
+      "data-[initialized=true]:ease-out",
     ],
     panel: [
       "py-3",