Kotlin 未解决的参考：btn_start 但我在我的布局中定义了它

Question

这是我在 activity_main.xml

中的代码

<Button
            android:id="@+id/btn_start"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="16dp"
            android:background="@color/white"
            android:text="Start"
            android:textColor="#757575"
            android:textSize="18sp">


        </Button>

但是当我编码时

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

它会给我错误提示未解决的引用 (btn_start)

Answer 1

Kotlin Android Extensions is deprecated, which means that using Kotlin synthetics for view binding is no longer supported.

请参考官方文档here

Kotlin 未解决的参考：btn_start 但我在我的布局中定义了它

Kotlin Unresolved reference: btn_start but i define it in my layout

android

reference

android-activity

kotlin