Load data from .plist to a TableView of iPhone

Question

I'm praticing example from Beginning iPhone 4 Development:Exploring the iOS SDK. In Chapter 8 it shows how to load data from a plist into a tableview. The example was done with Interface Builder. I want to do it by code but encounter problems. Nothing shows up on screen....

Here's the .h

#import <UIKit/UIKit.h>
@interface FifthViewController : UIViewController <UITableViewDataSource, UITableViewDelegate>
{
    NSDictionary *names;
    NSArray      *keys;
}
@property (nonatomic, retain) NSDictionary *names;
@property (nonatomic, retain) NSArray *keys;
@end

Here's .m

#import "FifthViewController.h"
@implementation FifthViewController
@synthesize names;
@synthesize keys;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

#pragma mark - View lifecycle

- (void)viewDidLoad
{
    [super viewDidLoad];

    UITableView *table = [[UITableView alloc]initWithFrame:CGRectMake(0, 0, 320, 367) style:UITableViewStyleGrouped];
    [table setDataSource:self];
    [table setDelegate:self];


    NSString *path = [[NSBundle mainBundle] pathForResource:@"sortednames"
                                                 ofType:@"plist"];
    NSDictionary *dict = [[NSDictionary alloc]
                      initWithContentsOfFile:path];
    self.names = dict;
    [dict release];

    NSArray *array = [[names allKeys] sortedArrayUsingSelector:
                  @selector(compare:)];
    self.keys = array;
    [self.view addSubview:table];
    [table release];
}

- (void)dealloc 
{
    [names release];
    [keys release];
    [super dealloc];    
}

- (void)viewDidUnload
{
    self.names = nil;
    self.keys = nil;
    [super viewDidUnload];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    // Return YES for supported orientations
    return (interfaceOrientation == UIInterfaceOrientationPortrait);
}

#pragma mark -
#pragma mark Table View Data Source Methods
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView 
{
    return [keys count];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section 
{
    NSString *key = [keys objectAtIndex:section];
    NSArray *nameSection = [names objectForKey:key];
    return [nameSection count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView
     cellForRowAtIndexPath:(NSIndexPath *)indexPath 
{
    NSUInteger section = [indexPath section];
    NSUInteger row = [indexPath row];

    NSString *key = [keys objectAtIndex:section];
    NSArray *nameSection = [names objectForKey:key];

    static NSString *SectionsTableIdentifier = @"SectionsTableIdentifier";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:
                         SectionsTableIdentifier];
    if (cell == nil) 
    {
        cell = [[[UITableViewCell alloc]
             initWithStyle:UITableViewCellStyleDefault
             reuseIdentifier:SectionsTableIdentifier] autorelease];
    }

    cell.textLabel.text = [nameSection objectAtIndex:row];
    return cell;
}

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

- (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView 
{
    return keys;
}

@end

Answer 1

There are a few issues with your code, but the root issue is that you're never adding the UITableView as a view/subview in your UIViewController:

UITableView *table = [[UITableView alloc]initWithFrame:CGRectMake(0, 0, 320, 367) style:UITableViewStyleGrouped];
[table setDataSource:self];
[table setDelegate:self];
[table release];

// These two lines are what you're missing:
self.view = table;
[table release];

Alternatively, you could create the interface in Interface Builder and avoid having to create this stuff programmatically.

In addition you should not be creating your UITableView where you are. viewDidLoad should be used to perform any additional operations after all your interface components have been created.

You should move the creation of your UITableView to the loadView method:

Check out the UIViewController class reference for more details