如何通过Nav Controller切换Fragment？Navigation Drawer导航失效求助

核心问题 #

你代码里的冲突导致导航失效：同时使用了navView.setupWithNavController()和自定义的setNavigationItemSelectedListener，后者覆盖了前者的默认导航逻辑，点击菜单时只执行关闭抽屉的操作，没有触发页面导航。

解决步骤 #

• 移除自定义导航选中监听器：setupWithNavController已经内置了「导航到对应Fragment + 关闭抽屉」的完整逻辑，不需要额外设置setNavigationItemSelectedListener。删除这段冗余代码：

  navView.setNavigationItemSelectedListener{
      when (it.itemId) {
          R.id.nav_dashboard -> {
              drawer.closeDrawer(GravityCompat.START)
          }
          R.id.nav_profile -> {
              drawer.closeDrawer(GravityCompat.START)
          }
      }
      true
  }
  

• 校验ID匹配关系：确保导航菜单（res/menu/nav_menu.xml）里的item id，和导航图（res/navigation/nav_graph.xml）中对应Fragment的id完全一致。比如：
  • 菜单中Dashboard的item id应为R.id.dashboardFragment，而非R.id.nav_dashboard
  • 菜单中Profile的item id应为R.id.profileFragment，而非R.id.nav_profile

修正后的完整代码示例 #

val navHostFragment = supportFragmentManager.findFragmentById(R.id.container) as NavHostFragment
navController = navHostFragment.navController
val navView: NavigationView = findViewById(R.id.nav_view)
appBarConfiguration = AppBarConfiguration(
    setOf(
        R.id.dashboardFragment,
        R.id.profileFragment,
    ), drawerLayout
)
setupActionBarWithNavController(navController!!, appBarConfiguration!!)
navView.setupWithNavController(navController!!) 

内容的提问来源于stack exchange，提问作者Nain Malik