Kotlin學習第二天----------------寫一個簡單的RecycleView加點擊事件

原創

2020-02-22 17:28

Activity部分，xml部分就是一個簡單的RecycleView


var mData  = ArrayList<String>()
override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    //查找控件
    val recycleView = findViewById<RecyclerView>(R.id.recyCleview)
    //設置排列方式
    recycleView.layoutManager = LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false)
    //給集合添加數據
    getDate()
    val adapter = KotlinRecycleAdater(mData,this)
    recycleView.adapter = adapter
    //RecycleView的點擊事件
    adapter!!.setOnKotlinItemClickListener(object : KotlinRecycleAdater.IKotlinItemClickListener{
        override fun onItemClickListener(position: Int) {
            Toast.makeText(applicationContext,mData!![position],Toast.LENGTH_SHORT).show()
        }

    })
}

private fun getDate(){
    for(i in 0..20){
        mData!!.add("我是數據"+i)
    }

}

然後是Adapter部分，切記創建時候要創建Kotlin的.kt文件，不能創建之前的.java文件，

不然沒法用kotlin，Adapter裏面也就是一個TextView

class KotlinRecycleAdater() : RecyclerView.Adapter<KotlinRecycleAdater.MyViewHolder>(){
    private var list : ArrayList<String>? = null
    private var context : Context? = null
    private var itemOnClick : IKotlinItemClickListener? = null

    constructor(list : ArrayList<String>?,context: Context) : this() {
        this.list = list
        this.context = context
    }

    override fun onCreateViewHolder(p0: ViewGroup, p1: Int): MyViewHolder {
        var view = LayoutInflater.from(context).inflate(R.layout.recycleview_item,p0,false)
        return MyViewHolder(view)
    }

    override fun getItemCount(): Int {
        return list?.size!!
    }

    override fun onBindViewHolder(p0: MyViewHolder, p1: Int) {
        p0?.text?.text = list!![p1]
        p0.itemView.setOnClickListener{
            itemOnClick!!.onItemClickListener(p1)
        }
    }

    class MyViewHolder(itemView : View) : RecyclerView.ViewHolder(itemView){
        var text : TextView = itemView.findViewById(R.id.text_item)
    }

    //自定義接口
    interface IKotlinItemClickListener {
        fun onItemClickListener(position: Int)
    }

    // 提供set方法
    fun setOnKotlinItemClickListener(itemClickListener: IKotlinItemClickListener) {
        this.itemOnClick = itemClickListener
    }

}

這樣一個RecycleView就完成了，要多low有多low哈哈。