Question

I’m new to iPhone development.
I try to operate the tableview.
So I saw some sample codes and books.
But I don’t understand what is the meaning of indexPath.

Here is a line of code.

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath ;

Please explain for me he indexPath parameter.

Answer 1

The NSIndexPath class represents the path to a specific node in a tree of nested array collections.

A table has sections and rows, to know where a row is you need to know the index of which section it is in and the index position it is at within that section.

UIKit adds a category to make it easier to work with UITableView‘s.

@interface NSIndexPath (UITableView)

+ (NSIndexPath *)indexPathForRow:(NSInteger)row inSection:(NSInteger)section;

@property(nonatomic,readonly) NSInteger section;
@property(nonatomic,readonly) NSInteger row;

@end