使用视图绑定将 onclicklistener 添加到回收器视图，kotlin

Question

尝试将 onclicklistener 添加到我的回收站视图中的项目，这将使用意图打开另一个活动。 我试过查找示例，但我只能找到使用 Java 或 Kotlin 示例但未使用视图绑定的示例。

package com.truuce.anotherrvtest

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.recyclerview.widget.GridLayoutManager

import com.truuce.anotherrvtest.databinding.ActivityHeroBinding

class HeroActivity : AppCompatActivity() {

    var binding: ActivityHeroBinding? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityHeroBinding.inflate(layoutInflater)
        setContentView(binding?.root)

        val adapter = CardAdapter(HeroList.heroList)
        binding?.heroRV?.adapter = adapter
        binding?.heroRV?.layoutManager = GridLayoutManager(applicationContext, 3)

    }

    override fun onDestroy() {
        super.onDestroy()
        binding = null
    }
}

package com.truuce.anotherrvtest

import android.content.Context
import android.content.Intent
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.ImageView
import android.widget.TextView
import androidx.recyclerview.widget.RecyclerView
import com.truuce.anotherrvtest.databinding.HeroCardBinding

class CardAdapter(val heroList: List<Hero>) : RecyclerView.Adapter<CardAdapter.MainViewHolder>() {

    inner class MainViewHolder(val heroBinding: HeroCardBinding) :
        RecyclerView.ViewHolder(heroBinding.root) { 
        fun bindHero(hero: Hero){
            heroBinding.heroNameTV.text = hero.heroName
            heroBinding.heroIV.setImageResource(hero.image)
        }

    }


    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MainViewHolder {


        return MainViewHolder(HeroCardBinding.inflate(LayoutInflater.from(parent.context), parent, false))
    }


    override fun onBindViewHolder(holder: MainViewHolder, position: Int) {
        val hero = heroList[position]
        holder.bindHero(hero)
    }


    override fun getItemCount() = heroList.size
}

尝试将 View.OnClickListener 添加到 MainViewHolder，然后实现一个成员。 OnClick(p0: View){}，但不知道如何让它工作。

Answer 1

您应该在适配器中为点击监听器添加一个功能属性。

Activity 可以设置项目点击侦听器行为。

class CardAdapter(
    val heroList: List<Hero>,
    val itemClickListener: (Hero)->Unit
) : RecyclerView.Adapter<CardAdapter.MainViewHolder>() {

    inner class MainViewHolder(val heroBinding: HeroCardBinding) :
        RecyclerView.ViewHolder(heroBinding.root) { 
        fun bindHero(hero: Hero) = with(heroBinding) {
            heroNameTV.text = hero.heroName
            heroIV.setImageResource(hero.image)
            root.setOnClickListener { itemClickListener(hero) }
        }

    }

    //...
}

// In Activity:

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityHeroBinding.inflate(layoutInflater)
        setContentView(binding?.root)

        val adapter = CardAdapter(HeroList.heroList) { hero ->
            // do something with hero item when it's clicked
        }
        binding?.heroRV?.adapter = adapter
        binding?.heroRV?.layoutManager = GridLayoutManager(applicationContext, 3)

    }