无法从匿名 class 访问外部 class

Question

我无法从匿名内部访问外部方法

class MyClass()
{
    fun doSomeStuff()
    {
       for (brandView in holder.brandImages)
       {
           brandView.onClick {
               if (brandView.brandId != null)
               {
                   notifyStateChanged()
               }
           }
       }
    }
    fun notifyStateChanged()
    {
        print("something")
    }
}

我遇到编译时错误：

Error:(46, 31) org.jetbrains.kotlin.codegen.CompilationException: Back-end (JVM) Internal error: Don't know how to generate outer expression for class <closure-BrandsBarView>
Cause: Don't know how to generate outer expression for class <closure-BrandsBarView>
File being compiled and position: (46,31) in C:/Users/piotr/IdeaProjects/MerciIt/app/src/main/java/pl/com/digita/merciit/app/ui/controls/colorswitcher/brandsbar/BrandsBarView.kt
PsiElement: {
                if (brandView.brandId != null)
                {
                    notifyStateChanged()
                    //brandView.setTicked(!brandView.isTicked)
                }
            }
The root cause was thrown at: CodegenContext.java:160
    at org.jetbrains.kotlin.codegen.ExpressionCodegen.genQualified(ExpressionCodegen.java:299)
(...)

那我做错了什么？

仅供理论讨论：

for (brandView in holder.brandImages)
{
    setupBrandView(brandView)
}

fun setupBrandView(brandView: BrandTickerView)
{
    brandView.onClick {brandView.isTicked = !brandView.isTicked; dataChanged?.invoke() }

}

工作正常

Answer 1

在匿名classes this指的是外部class。来自 object 外部 activity 必须明确引用

class MainActivity : Activity() {
    public override fun onCreate(savedInstanceState: Bundle?) {
...
        text_view.setOnClickListener{ v ->
            this.doActivityStuff()
        }
...
    fun doActivityStuff() {
        // do some stuff
    }
    text_view.setOnClickListener(object : View.OnClickListener {
        override fun onClick(v: View?) {
            this.onClick(v) // this refer to onClickListener
            this@MainActivity.doActivityStuff() // this refer to MainActivity
        }
    })
}

为了帮助解决您的情况，很高兴看到 classes 层次结构。

无法从匿名 class 访问外部 class

Can't access outer class from anonymous class

android

kotlin