recycleview出現(xiàn)已經(jīng)很久了，拖拽以及滑動刪除也很成熟了澳厢，實現(xiàn)方法也有很多，這次主要通過實現(xiàn)ItemTouchHelper來實現(xiàn)的
我不知道簡書怎么上傳錄屏 尷尬剩拢。线得。
先貼代碼吧
因為這個demo是在公司項目上寫的，所以一些基類就不貼了徐伐，不影響閱讀
拖拽輔助類

package com.gtxc.momiwow.Utils

import android.graphics.Canvas
import android.graphics.Color
import androidx.recyclerview.widget.ItemTouchHelper
import androidx.recyclerview.widget.RecyclerView
import com.blankj.utilcode.util.LogUtils

/**
 * http://www.reibang.com/p/8dec938d5ef8
 */
class ItemTouchHelperCallback(val listener: DragLister) : ItemTouchHelper.Callback() {
interface DragLister{
    fun onDragMoveSwap(adapterPosition: Int, adapterPosition1: Int):Boolean
    fun onSwipeDelete(adapterPosition: Int):Boolean
}

    interface StartDragListener {
        /**
         * 該接口用于需要主動回調(diào)拖拽效果的
         * @param viewHolder
         */
        fun onStartDrag(viewHolder: RecyclerView.ViewHolder?)
    }
    override fun getMovementFlags(
        recyclerView: RecyclerView,
        viewHolder: RecyclerView.ViewHolder
    ): Int {
        val dragflag =ItemTouchHelper.UP or ItemTouchHelper.DOWN
        val swipFlag =ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
        val flag = makeMovementFlags(dragflag,swipFlag)
        return flag
    }

    override fun isLongPressDragEnabled(): Boolean {
        return true
    }
    override fun onMove(
        recyclerView: RecyclerView,
        viewHolder: RecyclerView.ViewHolder,
        target: RecyclerView.ViewHolder
    ): Boolean {
       val result =  listener.onDragMoveSwap(viewHolder.adapterPosition,target.adapterPosition)
       return result
    }

    override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
        LogUtils.e("onSwiped")
              listener.onSwipeDelete(viewHolder.adapterPosition)
    }

    override fun onSelectedChanged(viewHolder: RecyclerView.ViewHolder?, actionState: Int) {
        if(actionState==ItemTouchHelper.ACTION_STATE_IDLE) return
        viewHolder?.itemView?.setBackgroundColor(Color.GRAY)
        super.onSelectedChanged(viewHolder, actionState)
    }

    override fun clearView(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder) {
        super.clearView(recyclerView, viewHolder)
        viewHolder?.itemView?.setBackgroundColor(Color.WHITE)
        viewHolder.itemView?.apply {
            alpha=1F
            scaleX=1F
            scaleY= 1F
        }
    }

    override fun onChildDraw(
        c: Canvas,
        recyclerView: RecyclerView,
        viewHolder: RecyclerView.ViewHolder,
        dX: Float,
        dY: Float,
        actionState: Int,
        isCurrentlyActive: Boolean
    ) {
        if(actionState==ItemTouchHelper.ACTION_STATE_SWIPE){
            val value = 1-Math.abs(dX)/viewHolder.itemView.width
            viewHolder.itemView.apply {
                alpha=value
                scaleY=value
                scaleX=value
            }
        }
        super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive)

    }
}

adapter

package com.gtxc.momiwow.ui.adapter

import android.annotation.SuppressLint
import android.content.Context
import android.view.LayoutInflater
import android.view.MotionEvent
import android.view.View
import android.view.ViewGroup
import android.widget.ImageView
import android.widget.TextView
import androidx.recyclerview.widget.RecyclerView
import com.blankj.utilcode.util.LogUtils
import com.chad.library.adapter.base.BaseQuickAdapter
import com.chad.library.adapter.base.BaseViewHolder
import com.gtxc.momiwow.R
import com.gtxc.momiwow.Utils.GlideUtils
import com.gtxc.momiwow.Utils.ItemTouchHelperCallback
import com.ksck.logoDesign.app.data.Detail
import com.youth.banner.adapter.BannerAdapter
import org.w3c.dom.Text
import java.util.*

/**
 * 自定義布局贯钩，下面是常見的圖片樣式，更多實現(xiàn)可以看demo，可以自己隨意發(fā)揮
 */
class DragAdapter() : BaseQuickAdapter<String, BaseViewHolder>(R.layout.item_drag),
    ItemTouchHelperCallback.DragLister {


    override fun convert(holder: BaseViewHolder?, item: String?) {
        val imageView = holder?.getView<ImageView>(R.id.ivBanners)
        holder?.setText(R.id.tvPosition,""+holder.layoutPosition)
        item?.let {
            if (imageView != null) {
                GlideUtils.loadImages(imageView, it)
            }
        }
    }


    override fun onDragMoveSwap(adapterPosition: Int, adapterPosition1: Int): Boolean {
        Collections.swap(data, adapterPosition, adapterPosition1);
        notifyItemMoved(adapterPosition, adapterPosition1);
        LogUtils.e("onDragMoveSwap")

        return true
    }

    override fun onSwipeDelete(adapterPosition: Int):Boolean {
        LogUtils.e("onSwipeDelete")
        data.removeAt(adapterPosition)
        notifyItemRemoved(adapterPosition)
        return true
    }


}

activity

package com.gtxc.momiwow.ui

import android.os.Bundle
import androidx.databinding.ViewDataBinding
import androidx.recyclerview.widget.GridLayoutManager
import androidx.recyclerview.widget.ItemTouchHelper
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.aleyn.mvvm.base.NoViewModel
import com.blankj.utilcode.util.LogUtils
import com.chad.library.adapter.base.listener.OnItemDragListener
import com.gtxc.momiwow.R
import com.gtxc.momiwow.Utils.ItemTouchHelperCallback
import com.gtxc.momiwow.Utils.clickDelay
import com.gtxc.momiwow.base.CommonBaseActivity
import com.gtxc.momiwow.ui.adapter.DragAdapter
import com.gtxc.momiwow.ui.adapter.ImageAdapter
import com.youth.banner.adapter.BannerAdapter
import kotlinx.android.synthetic.main.activity_drag.*
import java.util.*

class DragActivity : CommonBaseActivity<NoViewModel, ViewDataBinding>(),
    ItemTouchHelperCallback.StartDragListener {
    val bannerAdapter by lazy {
        DragAdapter()
    }
    val list = mutableListOf<String>(
      //圖片地址
    )
    lateinit var itemTouchHelper: ItemTouchHelper
    override fun layoutId(): Int {

        return R.layout.activity_drag
    }

    override fun initView(savedInstanceState: Bundle?) {
        super.initView(savedInstanceState)
    }

    override fun initData() {
        reset.clickDelay {
            list.addAll(
                mutableListOf<String>(
                    //圖片地址
                )
            )
            bannerAdapter.setNewData(list)
        }
        recycler.layoutManager = LinearLayoutManager(this)
        recycler.adapter = bannerAdapter
        bannerAdapter.setNewData(
            list
        )
        val callback = ItemTouchHelperCallback(bannerAdapter)
        itemTouchHelper = ItemTouchHelper(callback)
        itemTouchHelper.attachToRecyclerView(recycler)
    }

    override fun initCLick() {
    }

    override fun bindViewModel() {
    }

    override fun onStartDrag(viewHolder: RecyclerView.ViewHolder?) {
        if (viewHolder != null) {
            itemTouchHelper.startDrag(viewHolder)
        }
    }

}

但是這個有個問題 如果gridlayoutmanager的話 橫向刪除和拖拽就無效了,后續(xù)會看看網(wǎng)上其他方案是怎么解決的

Gridlayoutmanager代碼

    override fun getMovementFlags(
        recyclerView: RecyclerView,
        viewHolder: RecyclerView.ViewHolder
    ): Int {
        val layoutManager =
            recyclerView.layoutManager
        var dragFlags = 0
        var swipeFlags = 0
        if (layoutManager is GridLayoutManager) {
            // 如果是Grid布局角雷，則不能滑動祸穷，只能上下左右拖動
            dragFlags =
                ItemTouchHelper.UP or ItemTouchHelper.DOWN or ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
            swipeFlags = 0
        } else if (layoutManager is LinearLayoutManager) {
            // 如果是縱向Linear布局讨韭，則能上下拖動瘸爽，左右滑動
            if ((layoutManager as LinearLayoutManager?)?.orientation === LinearLayoutManager.VERTICAL) {
                dragFlags =
                    ItemTouchHelper.UP or ItemTouchHelper.DOWN
                swipeFlags =
                    ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
            } else {
                // 如果是橫向Linear布局，則能左右拖動谷徙，上下滑動
                swipeFlags =
                    ItemTouchHelper.UP or ItemTouchHelper.DOWN
                dragFlags =
                    ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
            }
        }
        return makeMovementFlags(
            dragFlags,
            swipeFlags
        )
    }