Question

我在Kotlin中遇到有关generic类型的一些问题。本来，我想用值和调用函数来调用函数。所以我在下面写下，但是该值只允许我传递类似string / Int这样的类型。我想在回调函数中将函数作为参数传递。

ClassA

ClassA<T>{
var canCancel: Boolean = true
var recallFunction: (() -> T)? = null
var recallFunctionWithValue: ((value: T) -> Unit)? = null
var context: Context? = null
var value: T? = null
var functionPara :( ()->T)? = null
var recallFunctionWithFunction:((()->T) -> Unit)? = null

constructor(context: Context?, canCancel: Boolean, value: T, recallFunctionWithValue: (value: T) -> Unit) {
this.context = context
this.canCancel = canCancel
this.value = value
this.recallFunctionWithValue = recallFunctionWithValue
}
}

ClassB

ClassA(ctx, true,viewModel!!::testRefInside,viewModel!!::testRefOutside).createNativeNetworkDialog()

ViewModel

fun testRefOutside(test: Observable<Any>? ){

}
fun testRefInside():Observable<Any>?{
    return null
}

我尝试做类似的事情

var canCancel: Boolean = true
var recallFunction: (() -> T)? = null
var recallFunctionWithValue: ((value: T) -> Unit)? = null
var context: Context? = null
var value: T? = null
var functionPara :( ()->T)? = null
var recallFunctionWithFunction:((()->T) -> Unit)? = null

    constructor(context: Context?, canCancel: Boolean, value: () -> T, recallFunctionWithValue: (value: ()->T) -> Unit) {
    this.context = context
    this.canCancel = canCancel
    this.functionPara = value
    this.recallFunctionWithFunction = recallFunctionWithValue
}

但是显示语法错误。有人可以帮忙吗？

语法错误

Error

Error2

Error show in this place only RYEasyDialog means ClassA

有效！！现在

  var recallFunctionWithFunction:((value: T) -> Unit)? = null
    constructor(context: Context?, canCancel: Boolean, value: () -> T, recallFunctionWithValue: (value: T) -> Unit) {
    this.context = context
    this.canCancel = canCancel
    this.functionPara = value
    this.recallFunctionWithFunction = recallFunctionWithValue

}

8/6更新 Vararg问题

我正在做高级操作。我只是将其发布在完整的代码中。如果我不使用vararg，则

EasyDialog<Observable<Any>,LiveData<Boolean>>(ctx, true,viewModel!!::callGetTeammateListAPITEST,recallFunctionWithFunction = viewModel!!::callMultipleAPI).createNativeNetworkDialog2()

不强制转换as ((Observable<Any>)->LiveData<Boolean>) 。但是callMuipleApi接收到vararg参数，我必须将其强制转换为（（Observable）-> LiveData），但是我没有显示任何错误，但函数callmutipleapi和callgetteammateslist没有被调用。有人可以帮忙吗？

ViewModel

fun callMultipleAPI( vararg  observable: Observable<Any>):LiveData<Boolean>{
    if(progressDialogData==null){
        progressDialogData= MutableLiveData()
    }
    progressDialogData?.setValue(true)
    repo.callMultipleAPI<Any>(*observable, observer = RYEasyObserver(object : RyObserverSingleStatusListener<List<Any>> {
        override fun onNext(g: List<Any>) {
            Log.d("test",g.toString())
            for(model in g){
                when(model){
                    is GetTeammateListModel ->{setCallGetTeammateListResponse(model)}
                    is GetTeamListModel ->{setCallGetTeamListResponse(model)}
                    is GetMessageSumModel->{setCallGetMessageSumResponse(model)}
                    is GetCallModel->{setCallGetResponse(model)}
                }
            }
            progressDialogData?.setValue(false)
        }


        override fun onError() {
            progressDialogData?.setValue(false)
        }

    },true))
    return progressDialogData!!
}

片段

EasyDialog<Observable<Any>,LiveData<Boolean>>(ctx, true,viewModel!!::callGetTeammateListAPITEST,recallFunctionWithFunction = viewModel!!::callMultipleAPI as ((Observable<Any>)->LiveData<Boolean>)).createNativeNetworkDialog2()

EasyDialog

class EasyDialog<T,V> {
var canCancel: Boolean = true
var recallFunction: (() -> T)? = null
var recallFunctionWithValue: ((value: T) -> Unit)? = null
var context: Context? = null
var value: T? = null
var functionPara :(()->T)? = null
var recallFunctionWithFunction:((T) -> V)? = null



    constructor(
    context: Context?, canCancel: Boolean, value: ()->T, recallFunctionWithFunction:  (T) -> V  ){
    this.context = context
    this.canCancel = canCancel
    this.functionPara = value
    this.recallFunctionWithFunction = recallFunctionWithFunction
}
    fun createNativeNetworkDialog2() {
    val builder = AlertDialog.Builder(context)
    if (!canCancel) {
        builder.setCancelable(false)
    } else {
        builder.setNegativeButton(context?.resources?.getString(R.string.gloda_cancel)) { dialogInterface, id -> }
    }
    builder.setMessage(context?.resources?.getString(R.string.global_network_error))
    builder.setPositiveButton(context?.resources?.getString(R.string.global_retry)) { dialog, id ->
        recallFunction?.invoke()
        value?.let { it1 -> recallFunctionWithValue?.invoke(it1) }
        //functionPara?.let { it2->recallFunctionWithFunction?.invoke(it2) }
        functionPara?.let{ functionPara->{ recallFunctionWithFunction?.let {
                recallFunctionWithFunction-> compose<T,V>(recallFunctionWithFunction  ,functionPara).invoke()
        }}}
    }

    val dialog = builder.create()
    dialog.show()
}
    fun <T, V> compose( f: (T) -> V,    g:() -> T ): () -> V {
            return {  f(g()) }
}

Answer 1

最后一个构造方法参数是

(() -> T) -> Unit

根据您为第三个构造函数参数传递的内容，推断T为Observable<Any>?。所以它期待一个

(() -> Observable<Any>?) -> Unit

但是testRefOutside是

 Observable<Any>? -> Unit

我猜您可能不是要通过将函数的输入设为另一个函数来定义三阶函数。

kotlin泛型类型作为参数

}

1 个答案: