https://seoft.tistory.com/11

rxjava 호출 후 1초간 재 호출이 안될경우 이벤트 실행.kt

package kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.ui.sub

import android.app.Activity
import android.content.Intent
import android.os.Bundle
import android.view.View
import androidx.lifecycle.Observer
import androidx.lifecycle.ViewModelProviders
import androidx.recyclerview.widget.DividerItemDecoration
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import io.reactivex.Observable
import io.reactivex.android.schedulers.AndroidSchedulers
import io.reactivex.disposables.SerialDisposable
import io.reactivex.schedulers.Schedulers
import kotlinx.android.synthetic.main.activity_sub.*
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.BuildConfig
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.R
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.data.BookRepo
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.data.api.createGsonFactory
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.data.api.createOkHttpFactory
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.data.api.createWebService
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.ui.ActivityHelper
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.util.get
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.util.setupActionBar
import kr.co.seoft.std_of_android_with_kt_mvvm_aac_mock.util.toast
import java.util.concurrent.TimeUnit


// ref
// https://blog.mindorks.com/understanding-rxjava-timer-delay-and-interval-operators
// https://brunch.co.kr/@tilltue/49

class SubActivity : ActivityHelper() {

    val TAG = "SubActivity"
    val DATE_FORMAT = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"
    val SEARCH_MAINTAIN_DELAY = 300L

    override val layoutResourceId = R.layout.activity_sub

    lateinit var vm: SubVM

    lateinit var rvBooks: RecyclerView
    private lateinit var adapter: BookAdapter
    private lateinit var lm: LinearLayoutManager

    var serialDisposable = SerialDisposable()

    lateinit var keyword: String

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_sub)

        vm = ViewModelProviders.of(
            this, SubVM(
                BookRepo(
                    createWebService(
                        createOkHttpFactory(),
                        createGsonFactory(DATE_FORMAT),
                        BuildConfig.BASE_URL
                    ), BuildConfig.AUTH_KEY
                )
            ).create()
        ).get(SubVM::class.java)

        initToolbar()
        initRecyclerView()
        initObservalble()

        keyword = intent.getStringExtra(ID_KEYWORD)

        vm.addData(keyword)
    }

    private fun initObservalble() {

        vm.doRefresh.observe(this, Observer {
            // vm.page -1 >> -1 : for offset +1 in addData's callback method
            adapter.notifyItemRangeChanged((vm.page - 1) * vm.COUNT_PER_PAGE, vm.refreshCount)
        })

        vm.doEmptyData.observe(this, Observer {
            "검색결과가 없습니다".toast()
            setResult(Activity.RESULT_CANCELED)
            finish()
        })

        vm.doFail.observe(this, Observer {
            "인터넷 연결을 확인해주세요".toast()
            setResult(Activity.RESULT_CANCELED)
            finish()
        })

        vm.doFailParse.observe(this, Observer {
            "알맞지 않은 양식이 들어왔습니다".toast()
        })

        vm.isLoading.observe(this, Observer {
            pbLoading.visibility = if (it) View.VISIBLE
            else View.INVISIBLE
        })
    }

    private fun initRecyclerView() {
        adapter = BookAdapter(vm.books, {
            val intent = Intent().apply {
                putExtra(ID_BOOK, it)
            }
            setResult(Activity.RESULT_OK, intent)
            finish()
        }, {
            keyword = it
            val disposable = Observable
                .timer(SEARCH_MAINTAIN_DELAY, TimeUnit.MILLISECONDS)
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe {

                    adapter.notifyItemRangeRemoved(1, vm.books.size - 1)
                    vm.clearBooks()
                    vm.addData(keyword)
                }
            serialDisposable.set(disposable)
        })

        lm = LinearLayoutManager(this)

        rvBooks = findViewById(R.id.rvBooks)
        rvBooks.layoutManager = lm
        rvBooks.adapter = adapter
        rvBooks.addItemDecoration(
            DividerItemDecoration(
                applicationContext,
                DividerItemDecoration.VERTICAL
            )
        )

        rvBooks.addOnScrollListener(object : RecyclerView.OnScrollListener() {
            override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
                super.onScrolled(recyclerView, dx, dy)

                if (!vm.isLoading.get() && !rvBooks.canScrollVertically(1) && dy > 0)
                    vm.addData(keyword)
            }
        })
    }

    private fun initToolbar() {
        setupActionBar(R.id.toolbar) {
            setDisplayShowTitleEnabled(true)
            setDisplayHomeAsUpEnabled(true)
            setHomeAsUpIndicator(R.drawable.ic_arrow_back_black)
        }
    }

    companion object {
        const val ID_KEYWORD = "ID_KEYWORD"
        const val ID_BOOK = "ID_BOOK"
    }
}