测验的故事板版本

Question

参考 iOS编程：Big Nerd Ranch指南的第一个测试项目Quiz，但是现在它使用NIB文件而不是Storyboard。所以我尝试自己做。

按照本书的代码，然后将其运行到模拟器中，屏幕将不显示任何内容。

// ViewController.m
#import "ViewController.h"

@interface ViewController ()

@property (nonatomic) int currentQuestionIndex;

@property (nonatomic, copy) NSArray *questions;
@property (nonatomic, copy) NSArray *answers;

@property (nonatomic, weak) IBOutlet UILabel *questionLabel;
@property (nonatomic, weak) IBOutlet UILabel *answerLabel;

@end

@implementation ViewController

- (id) initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    // Call the init method implemented by the superclass
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];

    if (self) {
        // create two arrays filled with questions and answers
        // and make the pointers point to them

        self.questions = @[@"From what is cognac made?",
                          @"What is 7+7?",
                          @"What is the capital of Vermont?"];

        self.answers = @[@"Grapes",
                         @"14",
                         @"Montpelier"];
    }

    // Return the address of the new object
    return self;
}

- (IBAction)showQuestion:(id)sender
{
    // Step to the next question
    self.currentQuestionIndex++;

    // Am I past the last question?
    if (self.currentQuestionIndex == [self.questions count]) {
        // Go back to the first question
        self.currentQuestionIndex = 0;
    }

    // Get the string at that index in the questions array
    NSString *question = self.questions[self.currentQuestionIndex];

    // Display the string in the question label
    self.questionLabel.text = question;

    // Reset the answer label
    self.answerLabel.text = @"???";
}

- (IBAction)showAnswer:(id)sender
{
    // What is the answer to the current question?
    NSString *answer = self.answers[self.currentQuestionIndex];

    // Display it in the answer label
    self.answerLabel.text = answer;
}

@end



// AppDelegate.m
#import "AppDelegate.h"
#import "ViewController.h"

@interface AppDelegate ()

@end

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch

    ViewController *quizVC = [[ViewController alloc] init];
    self.window.rootViewController = quizVC;

    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];

    return YES;
}

@end

我认为情节提要与NIB文件有所不同，因此，如果要实现情节提要的版本，应如何编写此代码。

我已经成功完成了该项目的所有其他工作。

此测验项目的其他信息。

Answer 1

在AppDelegate类中，用initWithNibName加载ViewController，

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch

    ViewController *quizVC = [[ViewController alloc] initWithNibName:@"YourNIBFileName" bundle:nil];
    self.window.rootViewController = quizVC;

    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];

    return YES;
}