android - kotlin - 未解决的参考：spinnerCourses

Question

请帮忙，我是 kotlin 的新手。我在布局文件中添加了一个微调器，并在 MainActivity 中创建了一个适配器，但我收到此错误未解决的参考：spinnerCourses 这是代码

class MainActivity : AppCompatActivity() {

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

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    setSupportActionBar(binding.toolbar)

    val dm = DataManager()
    val adapterCourses = ArrayAdapter<CourseInfo>(this,
    android.R.layout.simple_spinner_item,
    dm.courses.values.toList())
    adapterCourses.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)

    spinnerCourses.adapter = adapterCourses



}

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

override fun onOptionsItemSelected(item: MenuItem): Boolean {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    return when (item.itemId) {
        R.id.action_settings -> true
        else -> super.onOptionsItemSelected(item)
    }
}

}

标签： androidkotlin

Answer 1

Kotlin 合成绑定已被弃用，使用视图绑定，它就像一个魅力