Question

我有一个recyclerview，其中显示了学生详细信息列表。我面临的问题是，当我单击第一项时，它将返回第二项的数据。我相信它必须与getAdapterPosition()做些事情，但是我不确定该怎么做。

在这种情况下，当选择第一个学生时，它将返回第二个学生（项目）的卷号。感谢您的帮助

RecyclerViewAdapter

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

Context context;

public List<StudentDataModel> dataModels;


public StudentAdapter(List<StudentDataModel> getDataAdapter, Context context){

    super();

    this.dataModels = getDataAdapter;
    this.context = context;
}

public StudentDataModel dataAdapter;



@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.student, parent, false);

    ViewHolder viewHolder = new ViewHolder(view);

    return viewHolder;

}

@Override
public void onBindViewHolder(final StudentAdapter.ViewHolder viewHolder, final int position) {

     dataAdapter =  dataModels.get(position);

    viewHolder.NameStudentCard.setText(dataAdapter.getName());

    viewHolder.RankStudentCard.setText(dataAdapter.getRank());

    viewHolder.RollStudentCard.setText(dataAdapter.getRoll());


    viewHolder.itemView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            notifyDataSetChanged();


            Toast.makeText(v.getContext(), "Tapped on" + dataAdapter.getRoll(), Toast.LENGTH_SHORT).show(); //Here it returns the Roll No. of the second student(item) in the recyclerView.

            Intent intent = new Intent (v.getContext(), StudentDetailsActivity.class);

            v.getContext().startActivity(intent);
        }
    });

}




@Override
public int getItemCount() {

    return dataModels.size();
}


class ViewHolder extends RecyclerView.ViewHolder{

    public TextView NameStudentCard;
    public TextView RankStudentCard;
    public TextView RollStudentCard;

    public ViewHolder(View itemView) {

        super(itemView);

        NameStudentCard=(TextView)itemView.findViewById(R.id.textViewName);
        RankStudentCard=(TextView)itemView.findViewById(R.id.textViewRank);
        RollStudentCard =(TextView)itemView.findViewById(R.id.textViewEmployeeID);

    }
}

}

Answer 1

是的，因为您将对象声明为全局对象。因此它正在与最后一个可见行的对象进行更新，因为onBindViewHolder()被依次为每个可见行调用。因此，它仅适用于最后一个可见行。

所以您需要在方法内部声明它：

对此评论：

   // public StudentDataModel dataAdapter;

在这里声明：

@Override
public void onBindViewHolder(final StudentAdapter.ViewHolder viewHolder, final int position) {

   final StudentDataModel dataAdapter =  dataModels.get(position); // add this here

}

Answer 2

尝试此代码。使接口进入适配器类，以进行这种单击处理。.

 onItemClickListner onItemClickListner;

public void setOnItemClickListner(RecyclerViewAdpater.onItemClickListner onItemClickListner) {
    this.onItemClickListner = onItemClickListner;
}

 public interface onItemClickListner{
    void onItemClick(String data); // pass any data;
}


@Override
public void onBindViewHolder(ItemViewHolder holder, int position) {
    // below code handle click event on recycler view item.
    String data=mStringList.get(position);
    holder.textView.setText(data);
    holder.itemView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            onItemClickListner.onItemClick(data); //pass your data;
        }
    });
}

在将适配器绑定到recyclerview之后，适配器不为null，然后在下面的代码中调用。

    recyclerViewAdpater.setOnItemClickListner(new RecyclerViewAdpater.onItemClickListner() {
        @Override
        public void onItemClick(String data) {
            // perform your operation.
            recyclerViewAdpater.notifyDataSetChanged();
        }
    });

Answer 3

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

Context context;

public List<StudentDataModel> dataModels;


public StudentAdapter(List<StudentDataModel> getDataAdapter, Context context){

super();

this.dataModels = getDataAdapter;
this.context = context;
}

public StudentDataModel dataAdapter;


@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.student, parent, false);

    ViewHolder viewHolder = new ViewHolder(view);

    return viewHolder;

}

@Override
public void onBindViewHolder(final StudentAdapter.ViewHolder viewHolder, final int position) {

     dataAdapter =  dataModels.get(position);

    viewHolder.NameStudentCard.setText(dataAdapter.getName());

    viewHolder.RankStudentCard.setText(dataAdapter.getRank());

    viewHolder.RollStudentCard.setText(dataAdapter.getRoll());




}




@Override
public int getItemCount() {

    return dataModels.size();
}


class ViewHolder extends RecyclerView.ViewHolder{

    public TextView NameStudentCard;
    public TextView RankStudentCard;
    public TextView RollStudentCard;

    public ViewHolder(View itemView) {

        super(itemView);

        NameStudentCard=(TextView)itemView.findViewById(R.id.textViewName);
        RankStudentCard=(TextView)itemView.findViewById(R.id.textViewRank);
        RollStudentCard =(TextView)itemView.findViewById(R.id.textViewEmployeeID);

        itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Toast.makeText(v.getContext(), "Tapped on" + dataModels.get(getAdapterPosition()).getRoll(), Toast.LENGTH_SHORT).show(); 

                Intent intent = new Intent (v.getContext(), StudentDetailsActivity.class);

                v.getContext().startActivity(intent);
            }
        });

    }
}

}

RecyclerView onClick提供了错误的项目

3 个答案: