将数据从Recyclerview适配器传递到Fragment

Question

在我的片段课中

    public class ReceiveFragment extends Fragment implements ReceiverRecyclerViewAdapter.OnItemClick {

btnGenAddress.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {


                    linearLayoutMyWalletInfo.setVisibility(View.VISIBLE);
                    linearLayoutGenAddress.setVisibility(View.GONE);

                recyclerViewAdapter = new ReceiverRecyclerViewAdapter(getActivity(),subjects, emails,this);

                recyclerViewCardContainer.setAdapter(recyclerViewAdapter);



            }
        });

@Override
    public void onClick(String value) {

    }

在ReceiverRecyclerViewAdapter类中，我创建了一个接口，现在当我在片段中编写recyclerViewAdapter = new ReceiverRecyclerViewAdapter（getActivity（），主题，电子邮件，this）时； }它给人的complie时间错误，当我用“这个”参数。

和我的ReceiverRecyclerViewAdapter类

    public class ReceiverRecyclerViewAdapter extends RecyclerView.Adapter<ReceiverRecyclerViewAdapter.ViewHolder>{
     private OnItemClick mCallback;


    public ReceiverRecyclerViewAdapter(Context context1,String[] SubjectValues1, String[] SubjectValues2,OnItemClick listener){

            SubjectValues = SubjectValues1;
            EmailValues2 = SubjectValues2;

            context = context1;
            this.mCallback = listener;
        }

  public interface OnItemClick {
        void onClick(String value);
    }

  itemView.setOnClickListener(new View.OnClickListener(){
                @Override
                public void onClick(View v) {
                    // get position
                    int pos = getAdapterPosition();

                    // check if item still exists
                    if(pos != RecyclerView.NO_POSITION){
                        String clickedDataItem = SubjectValues[pos];
                       Toast.makeText(v.getContext(), "You clicked " + clickedDataItem, Toast.LENGTH_SHORT).show();
                        mCallback.onClick(clickedDataItem);
                    }
                }
            });
    }

Answer 1

您从片段传递了4个参数，但构造函数期望为3。因此，您需要将Context作为适配器中的第一个参数添加。

更新：

您正在匿名实例中传递this实例，该匿名类是未实现该接口的OnClickListener 。 因此，与其相反，请传递ReceiveFragment.this ，这样您就可以引用实现接口的片段：

recyclerViewAdapter = new ReceiverRecyclerViewAdapter(getActivity(),subjects, emails, ReceiveFragment.this);

Answer 2

问题是因为当您从OnClickListener传递this参数时，它传递的是on click实例，而不是该接口。 您可以像下面的代码一样在片段中初始化接口，然后在适配器中传递接口。

OnItemClick onitemClick = (OnItemClick) this;

btnGenAddress.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {


                linearLayoutMyWalletInfo.setVisibility(View.VISIBLE);
                linearLayoutGenAddress.setVisibility(View.GONE);

            recyclerViewAdapter = new ReceiverRecyclerViewAdapter(getActivity(),subjects, emails,onitemClick);

            recyclerViewCardContainer.setAdapter(recyclerViewAdapter);
        }
    });


 public class ReceiverRecyclerViewAdapter extends RecyclerView.Adapter<ReceiverRecyclerViewAdapter.ViewHolder>{

   private OnItemClick mCallback;

    public ReceiverRecyclerViewAdapter(Context context, String[] SubjectValues1, String[] SubjectValues2,OnItemClick listener){

        SubjectValues = SubjectValues1;
        EmailValues2 = SubjectValues2;

        this.context = context;
        this.mCallback = listener;
    } 

 public interface OnItemClick {
        void onClick(String value);
    }

  itemView.setOnClickListener(new View.OnClickListener(){
                @Override
                public void onClick(View v) {
                    // get position
                    int pos = getAdapterPosition();

                    // check if item still exists
                    if(pos != RecyclerView.NO_POSITION){
                        String clickedDataItem = SubjectValues[pos];
                       Toast.makeText(v.getContext(), "You clicked " + clickedDataItem, Toast.LENGTH_SHORT).show();
                        mCallback.onClick(clickedDataItem);
                    }
                }
            });
    }

Answer 3

尝试这个：

在适配器中：

编写public ReceiverRecyclerViewAdapter(Context context1,String[] SubjectValues1, String[] SubjectValues2,OnItemClick listener)

片段中：

1. 创建一个对象： OnItemClick onItemClick;

2. 在构造函数中： this.OnItemClick = onItemClick;

3. 在适配器中传递此对象。

活动中：

实现此listner 。