android - 代码在 lambda 表达式之外工作，但不能在内部工作

Question

我有以下代码:

override fun onCreate(savedInstanceState: Bundle?) {
    ...
    fab_action.setOnClickListener(actionSetMyLocationEnable) //passing my lambda
}

private val actionSetMyLocationEnable: (View) -> Unit = { it as FloatingActionButton
    it.isSelected = !it.isSelected
    setMyLocationEnable(it.isSelected) //this call work fine
}

private fun setMyLocationEnable(enable: Boolean) {
    if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
                != PackageManager.PERMISSION_GRANTED) {
        ActivityCompat.requestPermissions(
                this,
                arrayOf(Manifest.permission.ACCESS_FINE_LOCATION),
                PERMISSION_REQUEST_ACCESS_FINE_LOCATION)
        return //and this return work nice too
    }
    mMap.isMyLocationEnabled = enable
}

但是，当我按如下方式应用它时:

private val actionSetMyLocationEnable: (View) -> Unit = { it as FloatingActionButton
    it.isSelected = !it.isSelected
    if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
                != PackageManager.PERMISSION_GRANTED) {
        ActivityCompat.requestPermissions(
                this,
                arrayOf(Manifest.permission.ACCESS_FINE_LOCATION),
                PERMISSION_REQUEST_ACCESS_FINE_LOCATION)
        return //error 1
    }
    mMap.isMyLocationEnabled = it.isSelected //error 2
}

我遇到了这两个错误:

错误 1.

'return' is not allowed here

错误2.

Call requires permission which may be rejected by user: code should explicitly check to see if permission is available (with checkPermission) or explicitly handle a potential SecurityException

我知道每个错误的含义，但是

我的问题是:为什么我的代码在 lambda 表达式之外工作而在内部却不起作用？我该如何解决这个问题？

已更新

@Rene Ferrari's solution解决错误 1。非常感谢@Rene Ferrari

Answer 1

基于 mTak 回答我的解决方案如下:

private val actionSetMyLocationEnable: (View) -> Unit = returnHere@{ it as FloatingActionButton
    it.isSelected = !it.isSelected
    if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
                != PackageManager.PERMISSION_GRANTED) {
        ActivityCompat.requestPermissions(
                this,
                arrayOf(Manifest.permission.ACCESS_FINE_LOCATION),
                PERMISSION_REQUEST_ACCESS_FINE_LOCATION)
        return@returnHere //error 1
    }
    mMap.isMyLocationEnabled = it.isSelected //error 2
}

您基本上可以定义要返回的标签。这个标签当然可以命名为关键字以外的任何名称。在此示例中，我将其命名为 returnHere