如何处理 Kotlin function Android 中的简单错误

Question

I'm having trouble handling error in the following function. I'm basically new to Kotlin. Here's my RevenueCat Login Code and I want to handle::error in this code:

Purchases.sharedInstance.logInWith(
                    myUserID,
                    ::error // <- How to handle this? I want to retrieve error Code and Error Message.
            )
{ customerInfo, created  ->

// Handle Successful login here

}
          

Here's the code behind the function (within RevenueCat SDK)

@Suppress("unused")
fun Purchases.logInWith(
    appUserID: String,
    onError: (error: PurchasesError) -> Unit = ON_ERROR_STUB,
    onSuccess: (customerInfo: CustomerInfo, created: Boolean) -> Unit
) {
    logIn(appUserID, logInSuccessListener(onSuccess, onError))
}

Answer 1

The double colon in ::error is afunction reference . It is basically a reference to the function error() .

And from your logInWith() function, we have onError: (error: PurchasesError) -> Unit = ON_ERROR_STUB , meaning that the function should take PurchasesError as input parameter and does not need to return.

So we can derive a function as the following:

fun error(error: PurchasesError) {
    // And you can do something with the error here
}

Answer 2

I solved it like this:

Purchases.sharedInstance.logInWith(
     myUserID, 
 onError = { error -> 
        
        // Handle error here 
        
        }