如何消除iOS中的单元格之间的差距？

Question

我创建了一个UICollectionView，它有自定义单元格。现在主要是每个设备上单元格的高度宽度比率我添加了下面的代码。但是对于ipad我已经定义了修复高度/宽度但是在这种情况正在消除细胞之间的差距。请告诉我如何消除细胞之间的差距？

// 1
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{

    float first_width_per,first_height_per,final_width,final_height;

    first_width_per=((150/self.collectionView.frame.size.width)*100);
    first_height_per=((180/self.collectionView.frame.size.height)*100);
    first_width_per=46.875000;
    first_height_per=48.780487;
    final_width=((first_width_per*self.collectionView.frame.size.width)/100);
    final_height=((first_height_per*self.collectionView.frame.size.height)/100);
    if(IS_IPAD)
    {
        final_width=200;
        final_height=220;
    }
    return CGSizeMake(final_width, final_height);
}
// 3
- (UIEdgeInsets)collectionView:
(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section
{
    return UIEdgeInsetsMake(5, 5, 5, 5);
}
-(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section
{
    return 5
    ;

}
-(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section

{
    return 5;

}