NavigationView的使用

使用NavigationView实现侧滑菜单，并对里面的值进行相应的修改

这样就可以实现一个侧滑菜单
在android studio中选择新建Navigation Drawer Activity项目时会自动生成相关代码

注意 这个文件要放在res/menu路径下

class MainActivity : AppCompatActivity() {

    private lateinit var appBarConfiguration: AppBarConfiguration
    private lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)
        
        setSupportActionBar(binding.appBarMain.toolbar)
        
        val drawerLayout: DrawerLayout = binding.drawerLayout
        val navView: NavigationView = binding.navView //新建一个NavigationView的实例
        val navController = findNavController(R.id.nav_host_fragment_content_main)
        
        // Passing each menu ID as a set of Ids because each
        // menu should be considered as top level destinations.
        appBarConfiguration = AppBarConfiguration(
            setOf(
                R.id.nav_home, R.id.nav_gallery, R.id.nav_slideshow
            ), drawerLayout
        )
        setupActionBarWithNavController(navController, appBarConfiguration)
        navView.setupWithNavController(navController)

		//如果想改变NavigationView头部nav_username的内容时，就要根据刚刚新建的NavigationView
        val bundle = intent.extras;
        if (bundle != null) {
            val headerView: View = navView.getHeaderView(0);//得到头部
            val textName: TextView = headerView.findViewById(R.id.nav_username);
            textName.text = bundle.getString("username")
        }
    }

    override fun onCreateOptionsMenu(menu: Menu): Boolean {
        // Inflate the menu; this adds items to the action bar if it is present.
        menuInflater.inflate(R.menu.main, menu)
        return true
    }

    override fun onSupportNavigateUp(): Boolean {
        val navController = findNavController(R.id.nav_host_fragment_content_main)
        return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
    }
}

如果permission为0，nav_gallery和nav_slideshow不可见

val permission: Int = bundle.getInt("permission")
if (permission == 0){
    navView.menu.findItem(R.id.nav_gallery).isVisible = false
    navView.menu.findItem(R.id.nav_slideshow).isVisible = false
}