kotlin關于RecycleView簡單使用

1.添加builder ，引用recycleview

implementation 'com.android.support:recyclerview-v7:26+'
           

2.效果圖

3.主界面功能

package com.example.admin.zkotlin

import android.content.Context
import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.view.ViewGroup
import androidx.constraintlayout.widget.ConstraintLayout
import kotlinx.android.synthetic.main.activity_photo.*
import androidx.recyclerview.widget.DividerItemDecoration
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import kotlinx.android.synthetic.main.item_common.view.*

class MainActivity : AppCompatActivity() {
    var mDataList: ArrayList<Pair<Int, String>> = ArrayList();
    protected var mContext: Context? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_photo)
        mContext = this
        initData();
        initView()
    }

    private fun initData() {
        var index = 0
        mDataList.add(Pair(index++,"1限制布局 constraint layout demo"))
        mDataList.add(Pair(index++, "2面向對象六大原則(solid五大原則) >> "))
        mDataList.add(Pair(index++, "3-23種設計模式簡介 >> "))
        mDataList.add(Pair(index++, "4Rxjava >> "))
        //common_recycleview.adapter!!.notifyDataSetChanged()
    }

    private fun initView() {
        common_swipe.setOnRefreshListener {
            mDataList.add(0, Pair<Int, String>(mDataList.size + 1, "content00"))   Pair的類型可以不固定
            common_recycleview.adapter!!.notifyItemInserted(0)
            // common_swipe.setRefreshing(false)
            common_swipe.isRefreshing = false
        }
        common_recycleview.layoutManager = LinearLayoutManager(mContext)
        common_recycleview.adapter = MyAdapter()

        common_recycleview.addItemDecoration(DividerItemDecoration(mContext, DividerItemDecoration.HORIZONTAL))
    }

    inner class MyAdapter : RecyclerView.Adapter<MyViewHolder>(){
        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
            return MyViewHolder(layoutInflater.inflate(R.layout.item_common,parent,false))
        }

        override fun getItemCount(): Int {
            return mDataList.size
        }

        override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
            if (holder is MyViewHolder){
                var obj = mDataList.get(position) as Pair<Int,String>
                holder.apply {
                    holder.itemView.item_title.setText(obj.first.toString())
                    holder.itemView.item_content.setText(obj.second)
                    holder.itemView.setOnClickListener{v:View->
                        nextAct(obj.first,v)
                    }
                }
            }
        }

        private fun nextAct(first: Int, v: View) {
            var intent: Intent? = null
            when(first){
                0->intent = Intent(mContext,FirstActivity::class.java)
                1,2-> intent = Intent(mContext,TwoActivity::class.java)
                3-> intent = Intent(mContext,ThreeActivity::class.java)
            }
            intent?.let { startActivity(it) }
        }
    }

    inner class MyViewHolder(itemView: View?):RecyclerView.ViewHolder(itemView!!)

}
           

4.主界面布局

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
        android:id="@+id/common_swipe"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/common_recycleview"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

    </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>


</FrameLayout>
           

5.item界面布局 

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="?attr/selectableItemBackground"
    android:padding="@dimen/padding_10dp">

    <ImageView
        android:id="@+id/img_main"
        android:layout_width="@dimen/dimen_nor_60dp"
        android:layout_height="@dimen/dimen_nor_60dp"
        android:src="@mipmap/ic_launcher"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        tools:ignore="MissingConstraints" />

    <TextView
        android:id="@+id/item_title"
        style="@style/txt_nor_detail_title"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginLeft="@dimen/margin_10dp"
        app:layout_constraintLeft_toRightOf="@+id/img_main"
        app:layout_constraintRight_toLeftOf="@+id/img_arrow"
        tools:text="1111"
        tools:ignore="MissingConstraints" />

    <TextView
        android:id="@+id/item_content"
        style="@style/txt_nor_detail_content"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginLeft="@dimen/margin_10dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toRightOf="@+id/img_main"
        app:layout_constraintRight_toLeftOf="@+id/img_arrow"
        app:layout_constraintTop_toBottomOf="@+id/item_title"
        tools:text="2222" />

    <ImageView
        android:id="@+id/img_arrow"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@mipmap/ic_launcher"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>
           

end，還少了一點color  dimens  style  大家自行補上吧，随便寫點就行，那個并不重要