IOS Table View

A Table View usually needs to set its dataSource and delegate.
You can use Control + drag to set

And adopt two Protocols
@ Interface SecondViewController: UIViewController <UITableViewDelegate, UITableViewDataSource>
UITableViewDelegate is commonly used in the following methods:

// Called after the user changes the selection.- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath;// Called before the user changes the selection. Return a new indexPath, or nil, to change the proposed selection.- (NSIndexPath *)tableView:(UITableView *)tableView willSelectRowAtIndexPath:(NSIndexPath *)indexPath;// Variable height support- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath;

UITableViewDataSource is commonly used in the following methods:

@required- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section;// Row display. Implementers should *always* try to reuse cells by setting each cell's reuseIdentifier and querying for available reusable cells with dequeueReusableCellWithIdentifier:// Cell gets various attributes set automatically based on table (separators) and data source (accessory views, editing controls)- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath;

Note that the above @ required -- these two methods must be implemented, otherwise the program will fail.

How to Set Table View group display?
Implement the following function:

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {    NSArray *keys = [[[self artists] allKeys]                      sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];    return [keys objectAtIndex:section];}

Here artists is defined as NSDictionary * artists;
The above function implements grouping by keys in artists.

Implement the following table view style:

1 first, set the Style to grouped.

2. Implement the following functions:

-(NSString *) tableView :( UITableView *) tableView titleForHeaderInSection :( NSInteger) section
Set the title of each section. For example, UIButton and UIButtonTypeRoundedRect are the title of the Section.

-(NSInteger) tableView :( UITableView *) tableView numberOfRowsInSection :( NSInteger) section
Set the number of rows in each Section. The value is 2.

-(NSInteger) numberOfSectionsInTableView :( UITableView *) tableView
Total number of sections
The above functions are implemented based on the data you actually want to display.