fix:[19859]沉浸式播放，底部导航bar标题不展示

 import { BottomNavi, DisplayDirection } from 'wdConstant';
 import { BottomNavDTO, NavigationBodyDTO, TopNavDTO } from 'wdBean';
-import { EmitterEventId, EmitterUtils, Logger } from 'wdKit';
+import { EmitterEventId, EmitterUtils, Logger, StringUtils } from 'wdKit';
 import { HttpUtils } from 'wdNetwork/Index';
 import HomeChannelUtils, { AssignChannelParam } from 'wdRouter/Index';
 import { MinePageComponent } from 'wdComponent/src/main/ets/components/page/MinePageComponent';
@@ -170,7 +170,7 @@ export struct BottomNavigationComponent {
   private setTabbarNameCColor(navItem:BottomNavDTO) {
 
     if (this.isImmersive) {
-      return navItem.immersiveNameCColor
+      return StringUtils.isEmpty(navItem.immersiveNameCColor) ? "#ED2800" : navItem.immersiveNameCColor
     }
 
     if (this.isNight) {
@@ -183,7 +183,7 @@ export struct BottomNavigationComponent {
   private setTabbarNameColor(navItem:BottomNavDTO) {
 
     if (this.isImmersive) {
-      return navItem.immersiveNameColor
+      return StringUtils.isEmpty(navItem.immersiveNameColor) ? "#737B87" : navItem.immersiveNameColor
     }
     if (this.isNight) {
       return navItem.nightNameColor