Java 使用kotlin在菜单中创建可单击链接

我试着做一个底部导航，我有这个代码

val bottomNavigation = findViewById<View>(R.id.bottom_navigation) as 
  BottomNavigationView
    bottomNavigation.setOnNavigationItemSelectedListener { item ->
        when (item.itemId) {

            R.id.botom__nav__home ->
                // Action when tab 1 selected
                val intent = Intent(this, HomeActivity::class.java)
            R.id.botom__nav__profile ->
                // Action when tab 2 selected
                val intent = Intent(this, LikeActivity::class.java)
            else ->
                // Action when tab 3 selected
                val intent = Intent(this, ProfileActivity::class.java)
        }
        true
    }
    startActivityForResult(intent, 99)
}

对于“何时”中的每个元素

---

有人能帮我修复这些错误吗？

请删除此行中的

项->

bottomNavigation.setOnNavigationItemSelectedListener { item ->
    when (item.itemId) {` 

---

问题是您在when块内多次声明

val intent

。要解决这个问题，只需将意图声明移到when块之外，例如：

lateinit var intent:Intent
bottomNavigation.setOnNavigationItemSelectedListener { item ->
    when (item.itemId) {

        R.id.botom__nav__home ->
            // Action when tab 1 selected
            intent = Intent(this, HomeActivity::class.java)
        R.id.botom__nav__profile ->
            // Action when tab 2 selected
            intent = Intent(this, LikeActivity::class.java)
        else ->
            // Action when tab 3 selected
            intent = Intent(this, ProfileActivity::class.java)
    }
    true
}
startActivityForResult(intent, 99)

---

见下面donfuxx的回答。或者将->之后的每个元素用大括号括起来{val intent….}