Question

我有ArrayList＆lt; String＆gt;有6个项目{“1”，“2”，“3”，“4”，“5”，“6”}。

我用CardView代表这些项目。我想要向左滑动删除项目。

当我从数字2向右滑动时，它看起来像这样：http://imgur.com/5E9fwP0

如果我删除了数字5，它将删除数字2.如果我删除数字3，它将删除数字1.它似乎是完全随机的。

我在这里遗漏了什么吗？我该如何解决这个问题？

相关代码：

我的适配器：

public class ChoresAdapter extends RecyclerView.Adapter&lt;ChoresAdapter.ChoreViewHolder&gt;{

private ArrayList&lt;String&gt; chores;

public ChoresAdapter(ArrayList&lt;String&gt; chores){
    this.chores = chores;
}

@Override
public ChoreViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.single_cardview, parent, false);
    v.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

        }
    });
    ChoreViewHolder pvh = new ChoreViewHolder(v);
    return pvh;
}


@Override
public void onBindViewHolder(ChoreViewHolder holder, int position) {
    holder.choreName.setText(this.chores.get(position));
}

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

public void removeAt(int position) {
    this.chores.remove(position);
    notifyItemRemoved(position);
    notifyDataSetChanged();
}

public static class ChoreViewHolder extends RecyclerView.ViewHolder {
    CardView cv;
    public static TextView choreName;
    public static TextView personAge;
    public static ImageView personPhoto;

    ChoreViewHolder(View itemView) {
        super(itemView);
        cv = (CardView)itemView.findViewById(R.id.cv);
        choreName = (TextView)itemView.findViewById(R.id.chore_name);
    }
    }

  }

我片段中的相关代码：

    @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_chores, container, false);
    RecyclerView rv = (RecyclerView)view.findViewById(R.id.rv);
    rv.setHasFixedSize(true);

    LinearLayoutManager llm = new LinearLayoutManager(getActivity());
    rv.setLayoutManager(llm);
    chores = new ArrayList&lt;&gt;();
    chores.add("1");
    chores.add("2");
    chores.add("3");
    chores.add("4");
    chores.add("5");
    chores.add("6");
    adapter = new ChoresAdapter(chores);
    SwipeableRecyclerViewTouchListener swipeTouchListener =
            new SwipeableRecyclerViewTouchListener(rv,
                    new SwipeableRecyclerViewTouchListener.SwipeListener() {
                        @Override
                        public boolean canSwipe(int position) {
                            return true;
                        }

                        @Override
                        public void onDismissedBySwipeLeft(RecyclerView recyclerView, int[] reverseSortedPositions) {
                            for (int position : reverseSortedPositions) {
                                adapter.removeAt(position);
                            }
                        }

                        @Override
                        public void onDismissedBySwipeRight(RecyclerView recyclerView, int[] reverseSortedPositions) {
                            for (int position : reverseSortedPositions) {
                                adapter.removeAt(position);
                            }
                        }
                    });

    rv.addOnItemTouchListener(swipeTouchListener);
    rv.setAdapter(adapter);
    return view;
}

Answer 1

有点晚了，我只是遇到了同样的情况并得到了答案，只需使用

chores.remove(position);
adapter.notifyDataSetChanged();

您不需要在适配器类上执行此操作。

Answer 2

您可以使用以下代码（Android支持V7中的ItemTouchHelper.SimpleCallback）使用滑动手势从RecyclerView中删除卡片。从RecyclerView中滑动时，您还需要从ArrayList中删除元素。

ItemTouchHelper.SimpleCallback simpleItemTouchCallback = new ItemTouchHelper.SimpleCallback(0, ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT) {

    @Override
    public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) {
        return false;
    }

    @Override
    public void onSwiped(RecyclerView.ViewHolder viewHolder, int swipeDir) {
        chores.remove(viewHolder.getAdapterPosition());
        adapter.notifyItemRemoved(viewHolder.getAdapterPosition());
    }

    @Override
    public void onMoved(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, int fromPos, RecyclerView.ViewHolder target, int toPos, int x, int y) {
        super.onMoved(recyclerView, viewHolder, fromPos, target, toPos, x, y);
    }
};

ItemTouchHelper itemTouchHelper = new ItemTouchHelper(simpleItemTouchCallback);
itemTouchHelper.attachToRecyclerView(recList);

通过向右滑动从自定义RecycleView适配器中删除项目会使项目顺序混乱

2 个答案: