在Android中长按一个项目时，如何更改所有RecyclerView项目的可见性？

Question

I'm making a multiple selection RecyclerView in Android in order to delete the selected items.

Checkboxes are initially invisible, the main logic is when a single view is long clicked all checkboxes are visible.

I'm performing to long click in onBindViewHolder and only the one clicked is visible.

Here is my adapter :

  private Context mContext ;
private ArrayList<Picture> mData ;
private ArrayList<Picture> mDataFiltered;

public CoffretPicturesAdapter(Context mContext, ArrayList<Picture> mData) {
    this.mContext = mContext;
    this.mData = mData;
    this.mDataFiltered = mData;
}

@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view ;
    LayoutInflater mInflater = LayoutInflater.from(mContext);
    view = mInflater.inflate(R.layout.cardview_item_coffret,parent,false);
    return new MyViewHolder(view);
}

@Override
public Filter getFilter() {
    return new Filter() {
        @Override
        protected FilterResults performFiltering(CharSequence charSequence) {
            String charString = charSequence.toString();
            if (charString.isEmpty()) {
                mDataFiltered = mData;
            } else {
                ArrayList<Picture> filteredList = new ArrayList<>();
                for (Picture row : mData) {

                    // name match condition. this might differ depending on your requirement
                    // here we are looking for name or phone number match
                    if (row.getTitle().toLowerCase().contains(charString.toLowerCase())) {
                        filteredList.add(row);
                    }
                }

                mDataFiltered = filteredList;
            }

            FilterResults filterResults = new FilterResults();
            filterResults.values = mDataFiltered;
            return filterResults;
        }

        @Override
        protected void publishResults(CharSequence charSequence, FilterResults filterResults) {
            mDataFiltered = (ArrayList<Picture>) filterResults.values;
            notifyDataSetChanged();
        }
    };
}

@Override
public void onBindViewHolder(final MyViewHolder holder, final int position) {
    holder.coffret_title.setText(mDataFiltered.get(position).getTitle());
    Picasso.with(mContext).load(mDataFiltered.get(position).getUri()).placeholder(R.drawable.placeholder).resize(500,500).centerCrop().into(holder.coffret_thumbnail);
    holder.cardView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Toast.makeText(mContext, "" + mDataFiltered.get(position).getTitle(), Toast.LENGTH_SHORT).show();
            Intent intent = new Intent(mContext, SelectedPicPreviewActivity.class);
            intent.putExtra("image_url", mDataFiltered.get(position).getUri().toString());
            mContext.startActivity(intent);
        }
    });

    holder.cardView.setOnLongClickListener(new View.OnLongClickListener() {
        @Override
        public boolean onLongClick(View view) {
            holder.checkBox.setVisibility(View.VISIBLE);
            return true;
        }
    });
}

@Override
public int getItemCount() {
    return mDataFiltered.size();
}

public static class MyViewHolder extends RecyclerView.ViewHolder {

    TextView coffret_title;
    ImageView coffret_thumbnail;
    LinearLayout cardView ;
    CircleCheckBox checkBox;

    public MyViewHolder(View itemView) {
        super(itemView);

        coffret_title = (TextView) itemView.findViewById(R.id.coffret_title_id) ;
        coffret_thumbnail = (ImageView) itemView.findViewById(R.id.coffret_img_id);
        cardView = (LinearLayout) itemView.findViewById(R.id.cardview_id);
        checkBox = (CircleCheckBox) itemView.findViewById(R.id.circle_check_box);
    }
}

I wish you guys can help me find the problem and maybe tell me about the way adapter methods work.

Answer 1

I wish you create a boolean flag which will indicate visibility of all the checkboxes and call notifyDataSetChanged() to rebind items:

private boolean mAreCheckboxesVisible = false;
// ...
@Override
public void onBindViewHolder(final MyViewHolder holder, final int position) {
    // ...
    holder.checkBox.setVisibility(mAreCheckboxesVisible ? View.VISIBLE : View.GONE);
    holder.cardView.setOnLongClickListener(new View.OnLongClickListener() {
        @Override
        public boolean onLongClick(View view) {
            mAreCheckboxesVisible = true;
            notifyDataSetChanged();
            return true;
        }
    });
}

And if you want to escape selection mode:

mAreCheckboxesVisible = false;
notifyDataSetChanged();