Question

从活动中更改RecyclerView项的颜色。

我通过实现适配器回调接口来处理回收者视图项单击。我还将adapterPosition传递给活动中的回调函数以进行条件检查。

MyActivitiy类

@Override
public void onSideAClicked(List<Faq> dataList, int itemPosition) {
    sideA_ID = dataList.get(itemPosition).getId();
    positionA = itemPosition + 1;
    sideAisClicked = true;
    if (checkIfMatched())
        // Here checkIfMatched() is true then set new color to recyclerview item at position itemPosition or if possible make the item non clickable
}

MyAdapter类

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

SideAAdapterCallback callback;
private Context context;
private List<Faq> faqList;

public SideARecyclerViewAdapter(Context context, List<Faq> faqList, SideAAdapterCallback sideAAdapterCallback) {
    this.context = context;
    this.faqList = faqList;
    this.callback = sideAAdapterCallback;
}
public interface SideAAdapterCallback {
    void onSideAClicked(List<Faq> dataList, int position);
}

@Override
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
    View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.activity_list_items, viewGroup,false);
    ViewHolder mh = new ViewHolder(v);
    return mh;
}

@Override
public void onBindViewHolder(final ViewHolder viewHolder, final int i) {
    viewHolder.faq_position.setText((i + 1) + "");
    viewHolder.faq_question.setText(faqList.get(i).getQuestion());
}

@Override
public int getItemCount() {
    return (null != faqList ? faqList.size() : 0);
}


public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    private TextView faq_position;
    private TextView faq_question;

    public ViewHolder(View view) {
        super(view);

        this.faq_position = (TextView) view.findViewById(R.id.faq_position);
        this.faq_question = (TextView) view.findViewById(R.id.faq_question);

        this.itemView.setClickable(true);
        this.itemView.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        int position = getAdapterPosition();

        if (callback != null) {
            callback.onSideAClicked(faqList, position);
        }
    }

}

//如果checkIfMatched（）返回true，则将新颜色设置为recyclerview项目放在itemPosition位置，或者尽可能使该项目不可点击

Answer 1

要更改所选行的颜色，请在类级别的适配器int selectedPosition;中定义一个变量，并在onBindViewHolder()方法中执行以下操作：

if(selectedPosition == i){
   //Change row color
}
else{
   //Set default color
}

编辑：

如果要在一个活动中比较两个回收者视图中选定的位置，请在适配器中添加此方法：

void setSelected (int position){
  this.selectedPosition = position;
  notifyDataSetChanged();
}

在您的活动中通过回调获得selectedPostition并检查条件调用adapter.setSelected(position)

从活动中的项目单击回调函数更改回收者查看项目的颜色

1 个答案: