fix |> 20352 【UI】新闻频道，顶部频道区域，右侧缺少渐隐效果

@@ -299,19 +299,27 @@ export struct TopNavigationComponentNew {
         })
         .grayscale(this.GrayManage.get().isMourning() ? 1 : 0)
 
-      List({ scroller: this.listScroller }) {
-        ForEach(this.myChannelList, (navItem: TopNavDTO, index: number) => {
-          ListItem() {
-            this.tabBarBuilder(navItem, index)
-          }
-          .grayscale(this.GrayManage.get().isNewsMourning(`${navItem.channelId}`) ? 1 : 0)
+      Stack({alignContent: Alignment.Start}){
+        List({ scroller: this.listScroller }) {
+          ForEach(this.myChannelList, (navItem: TopNavDTO, index: number) => {
+            ListItem() {
+              this.tabBarBuilder(navItem, index)
+            }.blendMode(BlendMode.SRC_IN, BlendApplyType.OFFSCREEN)
+            .grayscale(this.GrayManage.get().isNewsMourning(`${navItem.channelId}`) ? 1 : 0)
+          })
+        }
+        .listDirection(Axis.Horizontal)
+        .linearGradient({
+          angle: 90,
+          colors: [[0x01000000, 0.0], [0xff000000, 0.05], [0xff000000, 0.95], [0x01000000, 1.0]]
         })
+        .blendMode(BlendMode.SRC_OVER, BlendApplyType.OFFSCREEN)
+        .scrollBar(BarState.Off)
+        .edgeEffect(EdgeEffect.None)
+        .constraintSize({ maxWidth: '100%' })
+        .height($r('app.float.top_tab_bar_height'))
       }
-      .listDirection(Axis.Horizontal)
-      .scrollBar(BarState.Off)
-      .edgeEffect(EdgeEffect.None)
       .padding({ left: 8, top: 0, right: 0 })
-      .height($r('app.float.top_tab_bar_height'))
       .id('tabList')
       .alignRules({
         'top': { 'anchor': 'topBar', 'align': VerticalAlign.Bottom },