CODEWITHSUNDEEP
androidandroid-recyclerviewgrid-layoutgridlayoutmanager
Dave
Dave

Reputation: 53

Android - GridLayoutManager - Load items in list vertically?

I have a list of let's say 20 items. I want to be able to load them like this

1 11
2 12
3 13
4 14
5 15
6 16
7 17
8 18
9 19
10 20

I'm using a RecyclerView with a GridLayoutManager Using GridLayoutManager(context, 2), it loads the items as follows 

1 2
3 4
5 6
7 8
....

Which isn't my desired output

Upvotes: 3

Views: 886

Answers (4)

zhangjin
zhangjin

Reputation: 167

GridLayoutManager is not same as LinearLayout,default orientation is VERTICAL,so you should set HORIZONTAL, means that if space is not enough , more items will rank horizontally,like this:

recyclerView.setLayoutManager(new GridLayoutManager(activity, 2, GridLayoutManager.HORIZONTAL, false));

Upvotes: 0

Basha K
Basha K

Reputation: 1519

The simplest way to achieve this would be sort the ArrayList accordingly to the required order, you pass the your arraylist to rearrangeTheArrayList function get the new ArrayList and pass this to recycler view Adaptor to achieve above mentioned order .

 public ArrayList<Integer> rearrangeTheArrayList(ArrayList<Integer> integerArrayList) {
    ArrayList<Integer> resultArrayList = new ArrayList<>();
    int halfLength = 0;
    if (integerArrayList.size() % 2 == 1) {
        halfLength = (integerArrayList.size() / 2) + 1;
    } else {
        halfLength = integerArrayList.size() / 2;
    }

    for (int i = 0; i < halfLength; i++) {
        resultArrayList.add(integerArrayList.get(i));
        if ( (i + halfLength)<(integerArrayList.size() )) {
            resultArrayList.add(integerArrayList.get(i + halfLength));
        }
    }
    return resultArrayList;
}

Upvotes: 2

nawaab saab
nawaab saab

Reputation: 1902

You may implement logic like this. It will work smoothly

override fun onBindViewHolder(holder: RecyclerView.ViewHolder, pos: Int) {
            var arraySize = 21
            var half = 0
            if (array % 2 == 0)
                half = array % 2
            else half = (array % 2 + 0.5).toInt()
            if (pos  % 2 == 0)
                print(pos)
            else print(half + pos)
        }

Upvotes: 0

Trần Đức T&#226;m
Trần Đức T&#226;m

Reputation: 4443

The GridLayoutManager always teachers the RecyclerView to draw from left to right and up to down. The reason's default scale of this view is vertical (or horizontal). It can't calculate how many rows should it show in this dynamic case. I have a solution for you. However, you should not keep this business logic.

All you need is one adapter with two view types and simple logic for indexing the right thing. Sample code:

public class SampleAdapter extends RecyclerView.Adapter<ViewHolder> {
    private final Context context;
    private List<Integer> listLeft;
    private List<Integer> listRight;

    public SampleAdapter (Context context) {
        this.context = context;
    }

    public void setListLeft(List<Integer> list) {
        this.listLeft = list;
    }

    public void setListRight(List<Integer> list) {
        this.listRight = list;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(context).inflate(R.layout.sample, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        int index = position / 2; // assumes there are two lists of equal lengths
        int viewType = getItemViewType(position);
        if (viewType == TYPE_1) {
            holder.textView.setText(listLeft.get(index).toString());
        } else if (viewType == TYPE_2) {
            holder.textView.setText(listRight.get(index).toString());
        }
    }

    @Override
    public int getItemCount() {
        return listLeft.size() + listRight.size();
    }

    @Override
    public int getItemViewType(int position) {
        return position % 2 == 0 ? VIEW_TYPE_1 : VIEW_TYPE_2;
    }
}

Draw order

Upvotes: 0

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