如何在Android上使用多个计时器进入recyclerView

Question

In my application i want use multiple CountDownerTimer for show offer times into RecyclerView .
For write this application i used Kotlin language.
I write below codes, but when scrolling on recyclerView 's items start again this timer !

My mean is, timer started from 4:19 sec, when scrolling on items and after 10sec show me 4:19 again instead of 4:09 !

Activity codes:

class MainActivity : AppCompatActivity() {

    private lateinit var apisList: ApisList
    private lateinit var retrofit: Retrofit
    private lateinit var todayAdapter: AuctionsTodayAdapter
    private val todayModel: MutableList<Today> = mutableListOf()
    private lateinit var layoutManager: RecyclerView.LayoutManager

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        //Initialize
        retrofit = ApiClient.instance
        apisList = retrofit.create(ApisList::class.java)
        todayAdapter = AuctionsTodayAdapter(themedContext, todayModel)
        layoutManager = LinearLayoutManager(themedContext)
        //RecyclerView
        main_list.setHasFixedSize(true)
        main_list.layoutManager = layoutManager
        main_list.adapter = todayAdapter

        if (isNetworkAvailable()) getData(1, 10)
    }

    private fun getData(page: Int, limit: Int) {
        main_loader.visibility = View.VISIBLE
        val call = apisList.getAuctionsToday(page, limit)
        call.let {
            it.enqueue(object : Callback<AuctionsTodayResponse> {
                override fun onFailure(call: Call<AuctionsTodayResponse>, t: Throwable) {
                    main_loader.visibility = View.GONE
                    Log.e("auctionsTodayList", t.message)
                }

                override fun onResponse(call: Call<AuctionsTodayResponse>, response: Response<AuctionsTodayResponse>) {
                    if (response.isSuccessful) {
                        response.body()?.let { itBody ->
                            main_loader.visibility = View.GONE
                            if (itBody.toString().isNotEmpty()) {
                                todayModel.clear()
                                todayModel.addAll(itBody.res.today)
                                todayAdapter.notifyDataSetChanged()
                            }
                        }
                    }
                }
            })
        }
    }
}

Adapter codes:

class AuctionsTodayAdapter(val context: Context, val model: MutableList<Today>) :
    RecyclerView.Adapter<AuctionsTodayAdapter.MyHolder>() {

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyHolder {
        val view = LayoutInflater.from(context).inflate(R.layout.row_main_list, parent, false)
        val holder = MyHolder(view)

        //holder.setIsRecyclable(false)

        return holder
    }

    override fun getItemCount(): Int {
        return model.size
    }

    override fun onBindViewHolder(holder: MyHolder, position: Int) {
        val modelUse = model[position]
        holder.setData(modelUse)



        if (holder.newCountDownTimer != null) {
            holder.newCountDownTimer!!.cancel()
        }
        var timer = modelUse.calculateEnd

        timer = timer * 1000

        holder.newCountDownTimer = object : CountDownTimer(timer, 1000) {
            override fun onTick(millisUntilFinished: Long) {
                var seconds = (millisUntilFinished / 1000).toInt()
                val hours = seconds / (60 * 60)
                val tempMint = seconds - hours * 60 * 60
                val minutes = tempMint / 60
                seconds = tempMint - minutes * 60
                holder.rowMain_timer.rowMain_timer.text =
                    String.format("%02d", hours) + ":" + String.format(
                        "%02d",
                        minutes
                    ) + ":" + String.format("%02d", seconds)
            }

            override fun onFinish() {
                holder.rowMain_timer.text = "00:00:00"
            }
        }.start()

    }

    inner class MyHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {

        var newCountDownTimer: CountDownTimer? = null

        lateinit var rowMain_timer: TextView

        init {
            rowMain_timer = itemView.findViewById(R.id.rowMain_timer)
        }

        fun setData(model: Today) {
            model.image.let {
                Glide.with(context)
                    .load(Constants.MAIN_BASE_URL + it)
                    .apply(RequestOptions.diskCacheStrategyOf(DiskCacheStrategy.RESOURCE))
                    .into(itemView.rowMain_img)
            }
            model.title.let { itemView.rowMain_title.text = it }
        }
}

How can I fix it?

Answer 1

Because your code is written that way.

onBindViewHolder(..) is called whenever you scroll up/down and the view goes outside of visible area. Then that view is recycled and bound again to new list item (from model list). That's how it got the name RecyclerView .

To solve your problem, you need to put your countdown timer initialization codes inside model list item initialization (eg Today constructor).

Then the countdown timer will start and remain running within the Today object and inside onBindViewHolder(..) just grab the remaining time value from that Today object.

Hope this helps!!

Update I am not experienced in kotlin. So you may need to modify it according to kotlin. At some point you have MutableList<Today> preparation code right?

while creating a Today object, pass the adapter object as a constructor parameter.

The following block should be inside your Today class.

 var newCountDownTimer : CountDownTimer var currentVal : String init { newCountDownTimer = object : CountDownTimer(timer, 1000) { override fun onTick(millisUntilFinished: Long) { var seconds = (millisUntilFinished / 1000).toInt() val hours = seconds / (60 * 60) val tempMint = seconds - hours * 60 * 60 val minutes = tempMint / 60 seconds = tempMint - minutes * 60 currentVal = String.format("%02d", hours) + ":" + String.format( "%02d", minutes ) + ":" + String.format("%02d", seconds) // call adapter.notifyItemChanged(..) here } override fun onFinish() { //here you should call the adapter.notifyItemChanged(..) function with the position of this model in the model list } }.start() }

your onBindViewHolder should look like this:

 override fun onBindViewHolder(holder: MyHolder, position: Int) { val modelUse = model[position] holder.setData(modelUse) }

inside Holder.setData(..) function add this code

rowMain_timer.text = model.currentVal

Let me know if it helps.

Answer 2

have you tried making use of 1. onSaveInstanceState(Bundle state) 2.Restore state in the onRestoreInstanceState() 3. and onResume() .

this way you can keep track on your RecyclerList data.