AddressBook通讯录右边索引条

- (void)viewDidLoad
{
[super viewDidLoad];
_table.dataSource = self;
_table.delegate = self;
//通过ASCRII码获得26位大写英文字母,将其设置为区头
_array = [[NSMutableArray alloc]init];
for (int i = 65; i<65+26; i++)
{
unichar ch = i;
NSString *str = [[NSString alloc]initWithCharacters:&ch length:1];
[_array addObject:str];
[str release];
}
NSLog(@"%@",_array);
}

//设置tableView的区头索引条(通讯录右边的索引条)
- (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView
{
return _array;
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
return [_array objectAtIndex:section];
}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return _array.count;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
if (section % 3 == 0)
{
return 5;
}
else if (section % 3 == 1)
{
return 7;
}
else
{
return 9;
}
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [_table dequeueReusableCellWithIdentifier:@"cell"];
if (!cell)
{
cell = [[[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"cell"]autorelease];
}
cell.textLabel.text = [NSString stringWithFormat:@"第%lu行",indexPath.row];
return cell;
}