GridView全角分隔符

Question

I have ArrayList of some data. ArrayList includes different category of objects (cat 1, cat 2, cat 3, ...). I want to display my list in GridView .

My xml looks:

 <GridView
                android:id="@+id/gv_my_grid"
                style="@style/fill_wrap"
                android:cacheColorHint="@null"
                android:layout_margin="10dp"
                android:numColumns="3"
                android:listSelector="@android:color/transparent"
                android:stretchMode="columnWidth"
                android:gravity="center"
                />

And all works great.

GridView looks like:

|item 1 (cat 1)| |item 2 (cat 1)| |item 3 (cat 1)|
|item 4 (cat 1)| |item 5 (cat 2)| |item 6 (cat 2)|
|item 7 (cat 3)| |item 8 (cat 3)| |item 9 (cat 3)|

But now I want to place full width horisontal separator line between different category items. It must look like:

___________category_1_____________________________
|item 1 (cat 1)| |item 2 (cat 1)| |item 3 (cat 1)|
|item 4 (cat 1)| 
___________category_2_____________________________
|item 5 (cat 2)| |item 6 (cat 2)|
___________category_1_____________________________
|item 7 (cat 3)| |item 8 (cat 3)| |item 9 (cat 3)|

Is this possible? Cause all what I found - only ListView implementation.

Edit:

I was asked to add the code for my adapter. I think getView method will be enough.

public View getView(int position, View view, ViewGroup viewGroup) {
        final Holder holder;
        final View cell;
        if (null == view) {
            cell = this.inflater.inflate(R.layout.gi_my_item, null);
            holder = new Holder(cell);
            cell.setTag(holder);
        } else {
            cell = view;
            holder = (Holder) cell.getTag();
        }
        holder.item = this.items.get(position);
        holder.textField.setText(holder.item.someText);
        return cell;
    }

Answer 1

I found that you can use RecyclerView with GridLayoutManager to do the stuff.

Here is the code how to do this.

GridLayoutManager manager = new GridLayoutManager(this, 3);

that creates the grid with three columns.

Use setSpanSizeLookup() method to have a callback to return the column span of each item.

manager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
            @Override
            public int getSpanSize(int position) {
                return (elementsAdapter.getItemViewType(position) == VIEW_HEADER) ? 3 : 1;
            }
        });

that will made three column span when it was the header type.

Also, you have to make two of RecyclerView.ViewHolder and use will need getItemViewType() to differ from item views and header views in your RecyclerView.Adapter .

I made some sample code for it.
https://github.com/j796160836/GridLayoutManagerDemo

---

Reference:
https://medium.com/android-bites/grid-layout-with-header-3f2966181c4d

Answer 2

To reach this purpose,,You have to composite GridView in a ListView . with a CustomAdapter you can do that, ListView as parent and GridView as row_item .