Multiple selection ; wrong index count; fillValue() not working properly

I have created code to select items on LongPress.

But when I select an item in a huge list say 20-30 elements, multiple items get selected automatically.

By logging i cam to conclusion that getCount() and fillValue() are not working properly.

For instance my list as 16 items, but at the time of creation its indexing like this:

total items 16,

item 1 at 0
item 2 at 1
item 3 at 2
item 4 at 3
item 5 at 4
item 6 at 5
item 7 at 0
item 8 at 1
item 9 at 2
.... and goes on

it always resets at 5,

getCount() is set to return the size of elements array which is 16.

Please help ASAP