Kotlin: показывать AlertDialog при нажатии на элемент RecycleView - PullRequest
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Kotlin: показывать AlertDialog при нажатии на элемент RecycleView

0 голосов
/ 23 марта 2020

Сейчас я учусь показывать AlertDialog при нажатии на элемент RecyclerView. Тем не менее, я не знаю, как установить адаптер для прослушивателя кликов. Не могли бы вы дать мне совет?

Во-первых, я попытался включить AlertDialog в это основное задание. Это правильная позиция?

MainActivity 

class MainActivity : AppCompatActivity() {

    private val foodList = listOf(
        FoodModel("Noodle", 2),
        FoodModel("Cake", 3),
        FoodModel("Pizza", 4),
        FoodModel("Stake", 5),
        FoodModel("Chicken", 4)
    )

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


        val adapter = FoodDataAdapter(foodList)
        adapter.notifyDataSetChanged()
        foodListView.adapter = adapter
        foodListView.layoutManager = LinearLayoutManager(this)

        fun onItemClick(item: FoodModel, position: Int) {
            val dialog = AlertDialog.Builder(this)
            dialog.setTitle("Item deletion")
            dialog.setMessage("Do you want to delete this item?")
            dialog.setPositiveButton("Yes", DialogInterface.OnClickListener { _, _ ->
            })
            dialog.setNegativeButton("No", DialogInterface.OnClickListener { _, _ ->
            })
            dialog.setNeutralButton("Cancel", DialogInterface.OnClickListener { _, _ ->
            })
            dialog.show()
        }
    }
}

Это адаптер. 

class FoodDataAdapter(val list: List<FoodModel>):RecyclerView.Adapter<FoodDataViewHolder>(){
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): FoodDataViewHolder {
        val view = LayoutInflater.from(parent.context).inflate(R.layout.item_food,parent,false)
        return FoodDataViewHolder(view)
    }

    override fun getItemCount(): Int {
       return list.count()
    }

    override fun onBindViewHolder(holder: FoodDataViewHolder, position: Int) {
        holder.containerView.nameText.text=list[position].name
        holder.containerView.priceText.text="${list[position].price}dollar"
    }
}

Держатель вида 

class FoodDataViewHolder(override val containerView: View) : RecyclerView.ViewHolder(containerView),LayoutContainer

Ответы [ 2 ]

1 голос
/ 23 марта 2020

Я отредактировал твой код. MainActivity: 

class MainActivity : AppCompatActivity(), FoodDataAdapter.OnItemClickListener {

var foodList = ArrayList<FoodModel>()
lateinit var adapter : FoodDataAdapter
override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    foodlist.add(FoodModel("Noodle", 2))
    foodlist.add(FoodModel("Cake", 3))
    foodlist.add(FoodModel("Pizza", 4))
    foodlist.add(FoodModel("Stake", 5))
    foodlist.add(FoodModel("Chicken", 4))

    adapter = FoodDataAdapter(foodList, this)
    foodListView.adapter = adapter
    foodListView.layoutManager = LinearLayoutManager(this)

}

override fun alertDialog(position: Int) {
    val dialog = AlertDialog.Builder(this)
    dialog.setTitle("Item deletion")
    dialog.setMessage("Do you want to delete this item?")
    dialog.setPositiveButton("Yes", DialogInterface.OnClickListener { _, _ -> 
    adapter.removeItem(position)
    })
    dialog.setNegativeButton("No", DialogInterface.OnClickListener { _, _ ->
    })
    dialog.setNeutralButton("Cancel", DialogInterface.OnClickListener { _, _ ->
    })
    dialog.show()
}
}

FoodDataAdapter: 

class FoodDataAdapter(var list: ArrayList<FoodModel>, var listener : FoodDataAdapter.OnItemClickListener):RecyclerView.Adapter<FoodDataAdapter.FoodDataViewHolder>(){

interface OnItemClickListener {
    fun alertDialog(position : Int)
}

override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): FoodDataViewHolder {
    val view = LayoutInflater.from(parent.context).inflate(R.layout.item_food,parent,false)
    return FoodDataViewHolder(view)
}

override fun getItemCount(): Int {
    return list.count()
}

fun removeItem(position: Int) {
    list.removeAt(position)
    notifyItemRemoved(position)
}

override fun onBindViewHolder(holder: FoodDataViewHolder, position: Int) {
    holder.nameText.text=list[position].name
    holder.priceText.text="${list[position].price}dollar"
}

inner class FoodDataViewHolder(containerView: View) : RecyclerView.ViewHolder(containerView),
    View.OnClickListener {

    var nameText: TextView = containerView.findViewById(R.id.nameText)
    var priceText: TextView = containerView.findViewById(R.id.priceText)

    init {
        containerView.setOnClickListener(this)
    }

    override fun onClick(v: View?) {
        listener.alertDialog(adapterPosition)
    }
}
}
0 голосов
/ 23 марта 2020

Я просто поместил код объявления для «removeAt» в конце Адаптера, например, 

class FoodDataAdapter(val list: List<FoodModel>,var itemClicklistener : OnItemClickListener):RecyclerView.Adapter<FoodDataAdapter.FoodDataViewHolder>() {

    interface OnItemClickListener {
        fun onItemClick(position: Int)
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): FoodDataViewHolder {
        val view = LayoutInflater.from(parent.context).inflate(R.layout.item_food, parent, false)
        return FoodDataViewHolder(view)
    }

    override fun getItemCount(): Int {
        return list.count()
    }

    fun removeItem(position: Int) {
        list.removeAt(position)
        notifyItemRemoved(position)
    }

    override fun onBindViewHolder(holder: FoodDataViewHolder, position: Int) {
        holder.nameText.text = list[position].name
        holder.priceText.text = "${list[position].price} dollar"
    }

    inner class FoodDataViewHolder(containerView: View) : RecyclerView.ViewHolder(containerView),
        View.OnClickListener {
        var nameText: TextView = containerView.findViewById(R.id.nameText)
        var priceText: TextView = containerView.findViewById(R.id.priceText)

        init {
            containerView.setOnClickListener(this)
        }

        override fun onClick(v: View?) {
            itemClicklistener.onItemClick(adapterPosition)
        }
    }
}

private fun Any.removeAt(position: Int) {

}

, а также изменил основное действие следующим образом. 

class MainActivity : AppCompatActivity(), FoodDataAdapter.OnItemClickListener {

    private val foodList = arrayListOf(
        FoodModel("Noodle", 3),
        FoodModel("Cake", 5),
        FoodModel("Pizza", 7),
        FoodModel("Stake", 8),
        FoodModel("Chicken", 8)
    )
    var adapter: FoodDataAdapter? = null

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

        adapter = FoodDataAdapter(foodList, this)
        foodListView.adapter = adapter
        foodListView.layoutManager = LinearLayoutManager(this)
    }

    override fun onItemClick(position: Int) {
        val dialog = AlertDialog.Builder(this)
        dialog.setTitle("Item deletion")
        dialog.setMessage("Do you want to delete this item?")
        dialog.setPositiveButton("Yes", DialogInterface.OnClickListener { _, _ ->
            adapter?.removeItem(position)
        })
        dialog.setNegativeButton("No", DialogInterface.OnClickListener { _, _ ->
        })
        dialog.setNeutralButton("Cancel", DialogInterface.OnClickListener { _, _ ->
        })
        dialog.show()
    }
}

И оно работает! но ... одна проблема ... после удаления списка появляется последний список. общее количество списка не уменьшилось ..

enter image description here enter image description here

LOL еще один "Цыпленок" подходит .. ты знаешь как это исправить?

...