Where can I download the code?


I’m on Chapter 27 “Your First iOS Application” of Objective-C Programming book using Xcode version 4.6.2 (4H1003).

I am getting an error in BNRAppDelegate.m on the line below. The error is: [color=#FF0000]/iTahDoodle/BNRAppDelegate.m:111:14: No visible @interface for ‘UITableViewCell’ declares the selector ‘initWithStyle:reuseIndentifier:’[/color]

Assistance, would be great but I’d like to be able look at the code from the author to make sure it runs and then compare the two without getting direct assistance from others.

Here is the full code for BNRAppDelegate.m:

[code]// BNRAppDelegate.m
// iTahDoodle

#import “BNRAppDelegate.h”

NSString *docPath()
NSArray *pathList = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
return [[pathList objectAtIndex:0] stringByAppendingPathComponent:@“data.td”];

@implementation BNRAppDelegate

#pragma mark - Application delegate callbacks

  • (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

    // Attempt to load an existing to-do dataset from an array stored on disk.
    NSArray *plist = [NSArray arrayWithContentsOfFile:docPath()];
    if (plist) {
    // IF there was a dataset available, copy it into our instance variable.
    tasks = [plist mutableCopy];
    } else {
    // Otherwise, just create an empty one to get us started.
    tasks = [[NSMutableArray alloc] init];

    // Is tasks empty?
    if ([tasks count] == 0) {
    // Put some strings in it.
    [tasks addObject:@“Walk the dogs”];
    [tasks addObject:@“Feed the hogs”];
    [tasks addObject:@“Chop the logs”];

    // UIWindow instance. A CGRect is a struct with an origin (x,y) and size (width, height)
    CGRect windowFrame = [[UIScreen mainScreen] bounds];
    UIWindow *theWindow = [[UIWindow alloc] initWithFrame:windowFrame];
    [self setWindow:theWindow];

    // Define the frame rectangles of hte 3 UI elements.
    // CGRectMake() creates a CGRect from (x, y, width, height).
    CGRect tableFrame = CGRectMake(0, 80, 320, 380);
    CGRect fieldFrame = CGRectMake(20, 40, 200, 31);
    CGRect buttonFrame = CGRectMake(228, 40, 72, 31);

    // Create and confgure the tablet view.
    taskTable = [[UITableView alloc] initWithFrame:tableFrame
    [taskTable setSeparatorStyle:UITableViewCellSeparatorStyleNone];

    // Make this object the table view’s dataSource
    [taskTable setDataSource:self];

    // Make this object the table view’s dataSource.
    [taskTable setDataSource:self];

    // Create and configure the text field where new tasks will be typed.
    taskField = [[UITextField alloc] initWithFrame:fieldFrame];
    [taskField setBorderStyle:UITextBorderStyleRoundedRect];
    [taskField setPlaceholder:@“Type a task, tap Insert”];

    // Create and configure a rounded rect Insert button.
    insertButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [insertButton setFrame:buttonFrame];

    // Buttons behave using a target/action callback.
    // Configure the Insert button’s action to call thisobject’s -addTask: method
    [insertButton addTarget:self

    // Give the button a title.
    [insertButton setTitle:@"Insert"

    // Add our 3 UI elements to the window.
    [[self window] addSubview:taskTable];
    [[self window] addSubview:taskField];
    [[self window] addSubview:insertButton];

    //Finalize the window and put it on the screen.
    [[self window] setBackgroundColor:[UIColor whiteColor]];
    [[self window] makeKeyAndVisible];

    return YES;

#pragma mark - Table View management

  • (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
    // Because this table view only has one section the number of rows in it wqual to the number of items in out tasks array.
    return [tasks count];

  • (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
    // To improve performance, we reconfigure cells in memory that have scrolled off the screen and hand them back with new contents instead of always creating new cells.
    // First, we check to see if there’s a cell avaialble for reuse.
    UITableViewCell *c = [taskTable dequeueReusableCellWithIdentifier:@“Cell”];

    if (!c) {
    // … and only allocate a new cell if none are available.
    c = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault

    // Then we reconfigure the cell based on the model object, in this case out toDoitems array.
    NSString *item = [tasks objectAtIndex:[indexPath row]];
    [[c textLabel] setText:item];

    // … and hand back to the table view the properly configured cell.
    return c;

  • (void)addTask:(id)sender
    // Get the to-do item
    NSString *t = [taskField text];

    // Quit here if taskField is empty
    if ([t isEqualToString:@""]) {

    // Add it to our working array
    [tasks addObject:t];
    // Refresh the table so that the new item shows up
    [taskTable reloadData];
    // And clear out the text field
    [taskField setText:@""];
    // Dismiss the keyboard
    [taskField resignFirstResponder];

  • (void)applicationWillResignActive:(UIApplication *)application
    // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
    // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.

  • (void)applicationDidEnterBackground:(UIApplication *)application
    // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
    // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
    [tasks writeToFile:docPath() atomically:YES];

  • (void)applicationWillEnterForeground:(UIApplication *)application
    // Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.

  • (void)applicationDidBecomeActive:(UIApplication *)application
    // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.

  • (void)applicationWillTerminate:(UIApplication *)application
    // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.


… and BNRAppDelegate.h:

[code]// BNRAppDelegate.h
// iTahDoodle

#import <UIKit/UIKit.h>

NSString *docPath(void);

@interface BNRAppDelegate : UIResponder <UIApplicationDelegate, UITableViewDataSource>
UITableView *taskTable;
UITextField *taskField;
UIButton *insertButton;

NSMutableArray *tasks;


  • (void)addTask:(id)sender;

@property (strong, nonatomic) UIWindow *window;



Typographical error: [color=#FF0000]reuseIndentifier[/color] should be reuseIdentifier

See: UITableViewCell Class Reference.


Thank you, ibex10.