指定为非空的参数为空：

Question

您好，我最近将我的项目从 java 转换为 kotlin，遇到了很多问题，这就是其中之一

我不知道到底想说什么，也不知道它指向错误所在的正确行，因为在第 12 行它指向的是“import com.example.myappnotfinal.R”

错误

Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkNotNullParameter, parameter menuInfo
        at com.example.myappnotfinal.AdaptersAndMore.PostAdapter$PostViewHolder.onCreateContextMenu(Unknown Source:12)

PostAdapter.kt

class PostAdapter     /* ShimmerFrameLayout shimmerFrameLayout; */(
    var mcontext: Context, var mUploads: List<Upload>
) : RecyclerView.Adapter<PostAdapter.PostViewHolder>() {
    private val postDiffUtil = PostDiffUtil()
    val postListDiffer = AsyncListDiffer(this, postDiffUtil)
    private var mListener: OnItemClickListener? = null
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): PostViewHolder {
        val view: View = LayoutInflater.from(parent.context)
            .inflate(R.layout.post_item_container_profile, parent, false)
        return PostViewHolder(view)
    }

    override fun onBindViewHolder(holder: PostViewHolder, position: Int) {
        val uploadCurrent = postListDiffer.currentList[position]
        val shimmer = ColorHighlightBuilder()
            .setBaseColor(Color.parseColor("#F3F3F3"))
            .setBaseAlpha(1f)
            .setHighlightColor(Color.parseColor("#E7E7E7"))
            .setHighlightAlpha(1f)
            .setDropoff(50f)
            .build()
        val shimmerDrawable = ShimmerDrawable()
        shimmerDrawable.setShimmer(shimmer)
        Glide.with(mcontext)
            .load(uploadCurrent.getmImageUrl())
            .diskCacheStrategy(DiskCacheStrategy.AUTOMATIC)
            .placeholder(shimmerDrawable)
            .centerCrop()
            .fitCenter()
            .into(holder.imageView)
    }

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

    fun setOnItemClickListener(listener: OnItemClickListener?) {
        mListener = listener
    }

    fun setUploads(upload: List<Upload>) {
        mUploads = upload
    }


    interface OnItemClickListener {
        fun onClick(view: View?)
        fun onItemClick(position: Int)
        fun onDeleteClick(position: Int)
    }

    inner class PostViewHolder internal constructor(itemView: View) :
        RecyclerView.ViewHolder(itemView), View.OnClickListener, OnCreateContextMenuListener,
        MenuItem.OnMenuItemClickListener {
        var imageView: ShapeableImageView = itemView.findViewById(R.id.imagePost)
        override fun onClick(v: View) {
            if (mListener != null) {
                val position = adapterPosition
                if (position != RecyclerView.NO_POSITION) {
                    mListener!!.onItemClick(position)
                }
            }
        }

        override fun onCreateContextMenu(menu: ContextMenu, v: View, menuInfo: ContextMenuInfo) {
            val delete = menu.add(Menu.NONE, 2, 2, "Delete")
            delete.setOnMenuItemClickListener(this)
        }

        override fun onMenuItemClick(item: MenuItem): Boolean {
            if (mListener != null) {
                val position = adapterPosition
                if (position != RecyclerView.NO_POSITION) {
                    if (item.itemId == 2) {
                        mListener!!.onDeleteClick(position)
                        return true
                    }
                }
            }
            return false
        }

        init {
            itemView.setOnClickListener(this)
            itemView.setOnCreateContextMenuListener(this)
        }
    }

    companion object
}

Answer 1

将 override fun onCreateContextMenu(menu: ContextMenu, v: View, menuInfo: ContextMenuInfo) 更改为 override fun onCreateContextMenu(menu: ContextMenu, v: View, menuInfo: ContextMenuInfo?) 因为 ContextMenuInfo 可以是 nullable

指定为非空的参数为空：

Parameter specified as non-null is null :

parameters

android

kotlin