安卓开发入门教程-UI控件_RecyclerView

关注 安卓007 ,免费获取全套安卓开发学习资料

什么是RecyclerView

RecyclerView是当前主流用于显示列表的UI控件.

基础样例 效果图

方案简要介绍

1. 在app模块build.gradle文件中增加如下依赖

implementation 'androidx.recyclerview:recyclerview:1.1.0'

2. 在activity对应的布局文件中增加RecyclerView

2. 新增一个Adapter用于展示列表中每一行内容(含对应布局文件) 详见下面完整代码中的RvAdapter及其布局文件.
3. 在activity中实例化Adapter,设置数据,并将adapter设置给RecyclerView

private fun initRecyclerView() {
    var dataList = getData()
    val adapter = RvAdapter()
    adapter.setData(dataList)
    recyclerView.adapter = adapter
    recyclerView.layoutManager = LinearLayoutManager(this)
}

private fun getData(): List {
    val dataList = ArrayList()
    for (index in 0 until 100) {
        val text = " 数据$index "
        dataList.add(text)
    }
    return dataList
}

完整代码

1. activity代码:MainActivity

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        initRecyclerView()
    }

    private fun initRecyclerView() {
        var dataList = getData()
        val adapter = RvAdapter()
        adapter.setData(dataList)
        recyclerView.adapter = adapter
        recyclerView.layoutManager = LinearLayoutManager(this)
    }

    private fun getData(): List {
        val dataList = ArrayList()
        for (index in 0 until 100) {
            val text = " 数据$index "
            dataList.add(text)
        }
        return dataList
    }
}

2. MainActivity对应布局文件: activity_main.xml

3. RecyclerView对应Adapter: RvAdapter

class RvAdapter : RecyclerView.Adapter() {
    private var mDataList = mutableListOf()
    private lateinit var mContext: Context
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        mContext = parent.context
        val view = LayoutInflater.from(mContext).inflate(R.layout.item_layout, parent, false)
        return ViewHolder(view)
    }

    override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
        val data = mDataList[position]
        //更新UI上nameTv展示内容
        holder.itemView.nameTv.text = data
        //设置点击事件
        holder.itemView.setOnClickListener {
            Toast.makeText(mContext, data, Toast.LENGTH_SHORT).show()
        }
    }

    fun setData(dataList: List) {
        mDataList.clear()
        mDataList.addAll(dataList)
        notifyDataSetChanged()
    }

    override fun getItemCount(): Int = mDataList.size

    class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView)
}

4. RvAdapter对应布局文件: item_layout.xml

基础样例完整源代码

https://gitee.com/cxyzy1/recyclerView_Demo

安卓开发入门教程系列汇总 开发语言学习

Kotlin语言基础

UI控件学习系列

UI控件_TextView UI控件_EditText UI控件_Button UI控件_ImageView UI控件_RadioButton UI控件_CheckBox UI控件_ProgressBar

关注头条号,第一时间获取最新文章: