recyclerview并列设置间距

布局文件中设置要显示几列

 <androidx.recyclerview.widget.RecyclerView
                android:id="@+id/recyclerview"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                app:layoutManager="androidx.recyclerview.widget.GridLayoutManager"
                app:spanCount="2" />

 recyclerview.addItemDecoration(new RecyclerView.ItemDecoration() {
    
    
            @Override
            public void getItemOffsets(@NonNull Rect outRect, @NonNull View view, @NonNull RecyclerView parent, @NonNull RecyclerView.State state) {
    
    
                super.getItemOffsets(outRect, view, parent, state);
                int position = parent.getChildAdapterPosition(view);
                int space = 5;
                //根据position确定item需要留出的位置
                switch (position % 2) {
    
    
                    case 0:
                        //位于左侧的item
                        outRect.right = space;
                        break;
                    case 1:
                        //位于右侧的item
                        outRect.left = space;
                        break;
                    default:
                        break;
                }
                //底部间距
                outRect.bottom = 12;
            }
        });