Question

我有一个适用于RecyclerView的以下适配器：

public class GreenAdapter extends RecyclerView.Adapter<GreenAdapter.NumberViewHolder> {

    private final String TAG = GreenAdapter.class.getSimpleName();

    private int mNumberItems;

    public GreenAdapter(int numberOfItems) {
        mNumberItems = numberOfItems;
    }

    @Override
    public NumberViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
        Context context = viewGroup.getContext();
        int layoutIdForListItem = R.layout.number_list_item;
        LayoutInflater inflater = LayoutInflater.from(context);
        boolean shouldAttachToParentImmediately = false;

        View view = inflater.inflate(layoutIdForListItem, viewGroup, shouldAttachToParentImmediately);
        NumberViewHolder viewHolder = new NumberViewHolder(view);

        return viewHolder;
    }

    @Override
    public void onBindViewHolder(NumberViewHolder holder, int position) {
        Log.d(TAG, "#" + position);
        holder.bind(position);
    }

    @Override
    public int getItemCount() {
        return mNumberItems;
    }

    class NumberViewHolder extends RecyclerView.ViewHolder {


        TextView listItemNumberView;


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

            listItemNumberView = (TextView) itemView.findViewById(R.id.TV1);
        }


        void bind(int listIndex) {
            String[] messages = getResources().getStringArray(R.array.messageArray);
             listItemNumberView.setText(messages[listIndex]);
        }
    }
}

我想要做的是让它的第一项更大。我的方法类似于下面的代码，但我想有更好的方法，对吧？

public class GreenAdapter extends RecyclerView.Adapter<GreenAdapter.NumberViewHolder> {

    boolean isFirst=true;

    private final String TAG = GreenAdapter.class.getSimpleName();

    private int mNumberItems;

    public GreenAdapter(int numberOfItems) {
        mNumberItems = numberOfItems;
    }

    @Override
    public NumberViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
        Context context = viewGroup.getContext();
        int layoutIdForListItem = R.layout.number_list_item;
        if(isFirst) {
            isFirst=false;
            layoutIdForListItem = R.layout.first;
        }
        LayoutInflater inflater = LayoutInflater.from(context);
        boolean shouldAttachToParentImmediately = false;

        View view = inflater.inflate(layoutIdForListItem, viewGroup, shouldAttachToParentImmediately);
        NumberViewHolder viewHolder = new NumberViewHolder(view);

        return viewHolder;
    }
    @Override
    public void onBindViewHolder(NumberViewHolder holder, int position) {
        Log.d(TAG, "#" + position);
        holder.bind(position);
    }

    @Override
    public int getItemCount() {
        return mNumberItems;
    }

    class NumberViewHolder extends RecyclerView.ViewHolder {


        TextView listItemNumberView;


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

            listItemNumberView = (TextView) itemView.findViewById(R.id.TV1);
        }


        void bind(int listIndex) {
            String[] messages = getResources().getStringArray(R.array.messageArray);
             listItemNumberView.setText(messages[listIndex]);
        }
    }
}

Answer 1

您应该覆盖getItemViewType方法。

样品

public class GreenAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private static final int VIEW_TYPE_LARGE = 1;
    private static final int VIEW_TYPE_REGULAR = 2;

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        if (viewType == VIEW_TYPE_LARGE) {
            // supply large layout
        }
        if (viewType == VIEW_TYPE_REGULAR) {
            // supply regular layout
        }
        return null;
    }

    @Override
    public int getItemViewType(int position) {
        return position == 0 ? VIEW_TYPE_LARGE : VIEW_TYPE_REGULAR;
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {

    }

    @Override
    public int getItemCount() {
        return 0;
    }
}

使RecyclerView的某些项目使用不同的FrameLayouts？

1 个答案: