isItemVisible method
Checks if the item at the given index is currently visible within the scroll view.
index is the target index of the item.
itemHeight is the height of a single item.
Implementation
bool isItemVisible(int index, double itemHeight) {
double itemOffset = index * itemHeight;
double itemEndOffset = itemOffset + itemHeight;
double currentPosition = position.pixels;
return currentPosition >= itemOffset && currentPosition <= itemEndOffset;
}