java

edt.textChanges()
            .subscribeOn(Schedulers.io())
            .observeOn(AndroidSchedulers.mainThread())
            .filter { it.isNotEmpty() }
            .map { t -> t.toString().toInt() }
            .filter { it -> (it % 2 == 0) }
            .map { it -> it.toString() }
            .subscribe { it ->
                runOnUiThread { Toast.makeText(this, it[it.lastIndex].toString(), Toast.LENGTH_SHORT).show() }
            }