GridLayoutManager - how to auto fit columns?

Question

I have a RecyclerView with a GridLayoutManager that displays Card Views. I want the cards to rearrange according to the screen size (the Google Play app does this kind of th

Answer 1

I tried @Riten answer and worked funtastic!! But I wasn't happy with the hardcoded "180" So I modified to this:

    public class ColumnQty {
    private int width, height, remaining;
    private DisplayMetrics displayMetrics;

    public ColumnQty(Context context, int viewId) {

        View view = View.inflate(context, viewId, null);
        view.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
        width = view.getMeasuredWidth();
        height = view.getMeasuredHeight();
        displayMetrics = context.getResources().getDisplayMetrics();
    }
    public int calculateNoOfColumns() {

        int numberOfColumns = displayMetrics.widthPixels / width;
        remaining = displayMetrics.widthPixels - (numberOfColumns * width);
//        System.out.println("\nRemaining\t" + remaining + "\nNumber Of Columns\t" + numberOfColumns);
        if (remaining / (2 * numberOfColumns) < 15) {
            numberOfColumns--;
            remaining = displayMetrics.widthPixels - (numberOfColumns * width);
        }
        return numberOfColumns;
    }
    public int calculateSpacing() {

        int numberOfColumns = calculateNoOfColumns();
//        System.out.println("\nNumber Of Columns\t"+ numberOfColumns+"\nRemaining Space\t"+remaining+"\nSpacing\t"+remaining/(2*numberOfColumns)+"\nWidth\t"+width+"\nHeight\t"+height+"\nDisplay DPI\t"+displayMetrics.densityDpi+"\nDisplay Metrics Width\t"+displayMetrics.widthPixels);
        return remaining / (2 * numberOfColumns);
    }
}

Where "viewId" is the layout to be used as views in the RecyclerView like in R.layout.item_for_recycler

Not sure though about the impact of View.inflate as I only use it to get the Width, nothing else.

Then on the GridLayoutManager I do:

GridLayoutManager gridLayoutManager = new GridLayoutManager(this, Utility.columnQty(this, R.layout.item_for_recycler));

UPDATE: I added more lines to the code as I use it to get a minimum width spacing in the Grid. Calculate spacing:

recyclerPatternsView.addItemDecoration(new GridSpacing(columnQty.calculateSpacing()));

GridSpacing:

public class GridSpacing extends RecyclerView.ItemDecoration {
    private final int spacing;

    public GridSpacing(int spacing) {
        this.spacing = spacing;
    }

    @Override
    public void getItemOffsets(@NonNull Rect outRect, @NonNull View view, @NonNull RecyclerView parent, @NonNull RecyclerView.State state) {
        outRect.left = spacing;
        outRect.right = spacing;
        outRect.bottom = spacing;
        outRect.top = spacing;
    }
}