Hint for people who come from android background and try to do shared code for ios. Most of `delega...

# multiplatform

[Michal Klimczak]

Hint for people who come from android background and try to do shared code for ios.

Most of delegates in ios are weak. You need to keep a strong reference somewhere for them to not get deallocated unexpectedly. This is even more problematic, because usually the problem doesn't manifest itself on debug build, only release build crash and the stacktrace is rubbish.

[Michal Klimczak]

This will occasionally fail

actual class XMLParser actual constructor(inputStreamWrapper: InputStreamWrapper) {

    private val realParser = NSXMLParser(inputStreamWrapper.inputStream)

    actual fun setDelegatingSaxHandler(handler: PlatformSpecificSaxHandler) {
        realParser.delegate = handler
    }

    actual fun parse() {
        realParser.parse()
    }

}

[Michal Klimczak]

This one is fine

actual class XMLParser actual constructor(inputStreamWrapper: InputStreamWrapper) {

    private val realParser = NSXMLParser(inputStreamWrapper.inputStream)

    private var currentHandler : PlatformSpecificSaxHandler? = null

    actual fun setDelegatingSaxHandler(handler: PlatformSpecificSaxHandler) {
        currentHandler = handler //keep the strong reference
        realParser.delegate = handler
    }

    actual fun parse() {
        realParser.parse()
        currentHandler = null
    }

}