スクロールの大枠の最適化

components/StationDiagram/ExGridView.tsx

@@ -1,9 +1,10 @@
-import { FC } from "react";
+import { FC, useRef, useState, useCallback } from "react";
 import { View, Text, ScrollView, useWindowDimensions } from "react-native";
 import { ExGridViewItem } from "./ExGridViewItem";
 import Animated, {
   useAnimatedStyle,
   useSharedValue,
+  runOnJS,
 } from "react-native-reanimated";
 import { Gesture, GestureDetector } from "react-native-gesture-handler";
 
@@ -31,28 +32,114 @@ export const ExGridView: FC<{
   // ドラッグ位置を保持する共有値
   const widthX = useSharedValue(width);
   const savedWidthX = useSharedValue(width);
+  const [scrollEnabled, setScrollEnabled] = useState(true);
+  const scrollRef = useRef<Animated.ScrollView>(null);
+  const [contentScrollPos, setContentScrollPos] = useState(0);
+
+  // ScrollViewの有効/無効を切り替える関数
+  const toggleScrollEnabled = useCallback((enabled: boolean) => {
+    setScrollEnabled(enabled);
+  }, []);
 
   // パンジェスチャー（ドラッグ）のハンドラー
   const pinchGesture = Gesture.Pinch()
     .onUpdate((e) => {
       const calc = savedWidthX.value * e.scale;
       widthX.value = calc > width ? calc : width;
+      //runOnJS(scrollToRightEnd)();
     })
     .onEnd(() => {
       savedWidthX.value = widthX.value;
     });
+
+  const gesture = Gesture.Pan()
+    .minPointers(2) // 最低2本指
+    .maxPointers(2) // 最大2本指
+    .onTouchesDown((e) => {
+      if (e.numberOfTouches >= 2) runOnJS(toggleScrollEnabled)(false);
+    })
+    .onTouchesUp((e) => {
+      runOnJS(toggleScrollEnabled)(true);
+    })
+    .onEnd((e) => {
+      runOnJS(toggleScrollEnabled)(true);
+    });
+  // ジェスチャーを組み合わせる
+  const composed = Gesture.Simultaneous(pinchGesture, gesture);
+
   // アニメーションスタイル
   const animatedStyle = useAnimatedStyle(() => ({
     width: widthX.value,
   }));
   return (
-    <GestureDetector gesture={pinchGesture}>
-      <ScrollView horizontal nestedScrollEnabled pinchGestureEnabled={false}>
+    <GestureDetector gesture={composed}>
+      <Animated.ScrollView
+        horizontal
+        nestedScrollEnabled
+        pinchGestureEnabled={false}
+        scrollEnabled={scrollEnabled}
+        onScroll={(d) => {
+          setContentScrollPos(d.nativeEvent.contentOffset.x);
+        }}
+        onContentSizeChange={(d) => {
+          if (d < contentScrollPos) {
+            scrollRef.current?.scrollToEnd();
+          }
+        }}
+        ref={scrollRef}
+        contentContainerStyle={{
+          flexDirection: "column",
+        }}
+      >
+        <Animated.View
+          style={[
+            {
+              backgroundColor: "white",
+              width: width - 50,
+              flexDirection: "row",
+            },
+            animatedStyle,
+          ]}
+        >
+          {Array.from({ length: 60 }, (_, i) => i + 1).map((num) => {
+            if (num % 5 === 0) {
+              return (
+                <Text
+                  key={num}
+                  style={{
+                    flex: 1,
+                    textAlign: "center",
+                    borderRightWidth: 0.5,
+                    borderColor: "#ccc",
+                    flexWrap: "nowrap",
+                    fontSize: 12,
+                  }}
+                >
+                  {num - 5}
+                </Text>
+              );
+            } else return <></>;
+          })}
+          <Text
+            style={{
+              flex: 1,
+              textAlign: "center",
+              borderRightWidth: 0.5,
+              borderColor: "#ccc",
+              flexWrap: "nowrap",
+              fontSize: 12,
+              width: 50
+            }}
+          >
+            (分)
+          </Text>
+        </Animated.View>
         <Animated.ScrollView
           style={[{ backgroundColor: "white", width: width }, animatedStyle]}
           pinchGestureEnabled={false}
           minimumZoomScale={0.5}
           maximumZoomScale={3.0}
+          scrollEnabled={scrollEnabled}
           stickyHeaderIndices={
             groupKeys.at(0) ? groupKeys.map((_, i) => i * 2) : []
           }
@@ -68,7 +155,8 @@ export const ExGridView: FC<{
               }}
               key={hour}
             >
-              <Text style={{ fontSize: 15 }}>{hour}時台</Text>
+              <Text style={{ fontSize: 15, zIndex: 1, backgroundColor: 'white', marginLeft: contentScrollPos }}>{hour}時台</Text>
+
             </View>,
             <View style={{ flexDirection: "row", position: "relative" }}>
               {groupedData[hour].map((d, i) => (
@@ -82,7 +170,7 @@ export const ExGridView: FC<{
             </View>,
           ])}
         </Animated.ScrollView>
-      </ScrollView>
+      </Animated.ScrollView>
     </GestureDetector>
   );
 };