[移动开发]kotlin ListView

适配器

class MyAdapter(val content: Context, val list: List<String>) : BaseAdapter() {
    override fun getCount(): Int {
        return list.size
    }
    override fun getItem(p0: Int): Any {
        return list.get(p0)
    }
    override fun getItemId(p0: Int): Long {
        return p0.toLong()
    }
    override fun getView(position: Int, convertView: View?, parent: ViewGroup?): View {
        var view = convertView
        var hold:ViewHolder?
        if (view==null){
            hold=ViewHolder()
            view=LayoutInflater.from(content).inflate(R.layout.activity_item,null)
            hold.str=view.findViewById(R.id.My_text)
            view.tag=hold
        }else{
            hold=view.tag as ViewHolder
        }
        hold.str!!.text=list.get(position)
        return view!!
    }
    inner class ViewHolder{
        var str: TextView? =null
    }
}

主类调用

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        initView()
    }
    private fun initView() {
        val My_listview = findViewById<ListView>(R.id.My_listview)
        var list = listOf("gu", "jack", "li", "fa")
        var myAdapter = MyAdapter(this, list)
        My_listview.adapter = myAdapter
    }
}