Table views are used to display grouped lists of cells. Here are some example of table views:
This guide provides a quick recipe for setting up and using a simple table view with Interface Builder and prototype cells.
The example we'll use throughout is a table with cities and state abbreviations.
Figure out what data you need to display in the table and how you're going to obtain this data. In our example, we have a static fixture which is a list of strings.
let data = ["New York, NY", "Los Angeles, CA", "Chicago, IL", "Houston, TX",
"Philadelphia, PA", "Phoenix, AZ", "San Diego, CA", "San Antonio, TX",
"Dallas, TX", "Detroit, MI", "San Jose, CA", "Indianapolis, IN",
"Jacksonville, FL", "San Francisco, CA", "Columbus, OH", "Austin, TX",
"Memphis, TN", "Baltimore, MD", "Charlotte, ND", "Fort Worth, TX"]NSArray *data;
- (void)viewDidLoad {
[super viewDidLoad];
data = @[@"New York, NY", @"Los Angeles, CA", @"Chicago, IL", @"Houston, TX",
@"Philadelphia, PA", @"Phoenix, AZ", @"San Diego, CA", @"San Antonio, TX",
@"Dallas, TX", @"Detroit, MI", @"San Jose, CA", @"Indianapolis, IN",
@"Jacksonville, FL", @"San Francisco, CA", @"Columbus, OH", @"Austin, TX",
@"Memphis, TN", @"Baltimore, MD", @"Charlotte, ND", @"Fort Worth, TX"];
}In your storyboard drag a Table View (not Table View Controller)
from the Object Library into your view controller. Add an outlet for
the table view in your view controller.
You'll need a way to describe the appearance of the cells in your table.
One way to design a reusable template for cells is to use prototype
cells. Drag a Table View Cell from the Object Library into
your table view. You can now design the layout of the prototype cell
by adding more components from the Object Library.
Select File -> New -> File... -> iOS -> Source -> Cocoa Touch Class
and create a new subclass of UITableViewCell. Make sure to select Swift as the language as well:
Back in Interface Builder select your prototype cell, and in the Identity Inspector, set its custom class property to the new class you just created.
Open the Assistant Editor (two overlapping rings view) and select your custom class. Add outlets for elements you need to configure. You might need to add code to provide an easy way to configure the cell.
The example cell is simple enough that we don't have to do anything special. It just has two labels one for the city and one for the state abbreviation.
class DemoPrototypeCell: UITableViewCell {
@IBOutlet weak var cityLabel: UILabel!
@IBOutlet weak var stateLabel: UILabel!
}// DemoPrototypeCell.h
#import <UIKit/UIKit.h>
@interface DemoPrototypeCell : UITableViewCell
@property (weak, nonatomic) IBOutlet UILabel *cityLabel;
@property (weak, nonatomic) IBOutlet UILabel *stateLabel;
@endYou'll need a way to tell the table view to create and reuse instances of this prototype cell. Select the cell and give it a unique identifier in the Attributes Inspector.
Declare your view controller to implement the UITableViewDataSource
and UITableViewDelegate protocols. In your view controller's
viewDidLoad method, set the table view's data source and delegate
properties to your view controller.
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
@IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
tableView.dataSource = self
tableView.delegate = self
}
}
// ViewController.h
#import <UIKit/UIKit.h>
@interface ViewController : UIViewController <UITableViewDataSource, UITableViewDelegate>
@property (weak, nonatomic) IBOutlet UITableView *tableView;
@end
// ViewController.m
#import "ViewController.h"
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.tableView.dataSource = self;
self.tableView.delegate = self;
}
@endImplement methods from the UITableViewDataSource protocol in order to
tell the table what data to show in its table.
Return the total number of rows from the numberOfRowsInSection method.
The cellForRowAtIndexPath requires that a table view cell is obtained,
configured with the correct data and returned. Get an instance of the
prototype cell by calling dequeueReusableCellWithIdentifier on the
table view and passing it the identifier that was set in Step
6.
import UIKit
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
@IBOutlet weak var tableView: UITableView!
let data = ["New York, NY", ..., "Fort Worth, TX"]
override func viewDidLoad() {
super.viewDidLoad()
tableView.dataSource = self
tableView.delegate = self
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "com.codepath.DemoPrototypeCell", for: indexPath) as! DemoPrototypeCell
let cityState = data[indexPath.row].components(separatedBy: ", ")
cell.cityLabel.text = cityState.first
cell.stateLabel.text = cityState.last
return cell
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return data.count
}
}// ViewController.m
#import "ViewController.h"
#import "DemoPrototypeCell.h"
@implementation ViewController
NSArray *data;
- (void)viewDidLoad {
[super viewDidLoad];
data = @[@"New York, NY", @"Los Angeles, CA", @"Chicago, IL", @"Houston, TX",
@"Philadelphia, PA", @"Phoenix, AZ", @"San Diego, CA", @"San Antonio, TX",
@"Dallas, TX", @"Detroit, MI", @"San Jose, CA", @"Indianapolis, IN",
@"Jacksonville, FL", @"San Francisco, CA", @"Columbus, OH", @"Austin, TX",
@"Memphis, TN", @"Baltimore, MD", @"Charlotte, ND", @"Fort Worth, TX"];
self.tableView.dataSource = self;
self.tableView.delegate = self;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
DemoPrototypeCell *cell = [tableView dequeueReusableCellWithIdentifier:@"com.codepath.DemoPrototypeCell" forIndexPath:indexPath];
NSArray *cityState = [data[indexPath.row] componentsSeparatedByString:@", "];
cell.cityLabel.text = cityState.firstObject;
cell.stateLabel.text = cityState.lastObject;
return cell;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
return data.count;
}
This section covers some common issues that arise when using table view cells.
Sometimes you'll have cells that vary in height. The easiest way to have your rows be correctly sized is to set an estimatedRowHeight and
set the table view's rowHeight to UITableViewAutomaticDimension.
This only works in iOS 8 and above. For a discussion of other ways to
have variable row heights see our more in depth table view
guide.
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
@IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
tableView.dataSource = self
tableView.estimatedRowHeight = 100
tableView.rowHeight = UITableViewAutomaticDimension
}
...
}// ViewController.m
#import "ViewController.h"
@implementation ViewController
...
- (void)viewDidLoad {
[super viewDidLoad];
self.tableView.dataSource = self;
self.tableView.estimatedRowHeight = 100;
self.tableView.rowHeight = UITableViewAutomaticDimension;
}
...
@endThe most common event you'll need respond to is the user selecting a row in the table.
A common behavior when a row is selected, is to push a new view
controller with details about that row. You can do this in a storyboard
by control-dragging from the cell and selecting the appropriate segue
under the Selection Segue section.
You can also respond programmatically by implementing the
UITableViewDelegate method didSelectRowAtIndexPath:.
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
tableView.deselectRow(at: indexPath, animated: true)
// do something here
}- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[tableView deselectRowAtIndexPath:indexPath animated:true];
// do something here
}