How can I refactor my code in Kotlin without Casting?

Question

I want to know, How can I write code without activity casting like a fragment?....

--------- A Fragment

        tempMainImage.setOnClickListener {
            val message = "how are you today"

            (activity as? MainActivity).let {
                it?.onReplaceTtsFragment(message)
            }
        }

---------- MainActivity

fun onCloseTtsFragmentLayout() {
        detailFragmentLayout.visibility = View.GONE
    }

    fun onReplaceTtsFragment(message: String) {
        supportFragmentManager.beginTransaction().replace(R.id.detailFragmentLayout, TtsDetailFragment.newInstance(message, ::onCloseTtsFragmentLayout)).commit()

        detailFragmentLayout.visibility = View.VISIBLE
    }

Instead of casting activity `(getActivity())` you can either use interface or event bus to replace another fragment from fragment refer this answer https://stackoverflow.com/a/15007656/10097275 — nik, Jan 20 '20 at 05:13
well, casting doesn't have problem. but I just wanted to try to use lambda interface :) — soyLen, Jan 27 '20 at 06:36

score 0 · Answer 1 · answered Jan 20 '20 at 05:52

0

why not try using when block and the is keyword.

tempMainImage.setOnClickListener {
    val message = "how are you today"

    when (activity) {
        is MainActivity -> activity.onReplaceTtsFragment(message)
        else -> return
    }

answered Jan 20 '20 at 05:52

Ryan

948
6
20

score 0 · Answer 2 · answered Jan 20 '20 at 06:14

0

is is the kotlin replacement for instanceof in java

tempMainImage.setOnClickListener {
    val message = "how are you today"

    if(activity is MainActivity) {
        activity?.onReplaceTtsFragment(message)
    }
}

answered Jan 20 '20 at 06:14

Pavan Varma

1,199
1
9
21

How can I refactor my code in Kotlin without Casting?

2 Answers2