Ios 游戏中的未知错误（XCode）

我正在XCode上制作第二个游戏，代码似乎有问题。这是一款太空射击游戏，玩家跟随你的手指，点击释放导弹。问题是。。。当我按下“开始游戏”时，所有内容都隐藏起来，不会弹出。这是我的viewcontroller.h和viewcontroller.m

ViewController.m

#import "ViewController.h"

@interface ViewController ()

@end

int score;
int lives;
int enemyAttackOccurence;
int enemyPosition;
int randomSpeed;
float enemySpeed;

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

@implementation PlayViewController

-(void)viewDidAppear:(BOOL)animated {

    // Images that are to be hidden
    playerShip.hidden = YES;
    enemyShip.hidden = YES;
    missile.hidden = YES;
    earth.hidden = YES;

    // Hidden Labels
    scoreLabel.hidden = YES;
    livesLabel.hidden = YES;

    // Set score and lives remaining
    score = 0;
    lives = 0;

    // Strings
    scoreString = [NSString stringWithFormat:@"Score: 0"];
    liveString = [NSString stringWithFormat:@"Lives: 0"];

    // Initial Label Text
    scoreLabel.text = scoreString;
    livesLabel.text = liveString;

    // Image starting positions
    playerShip.center = CGPointMake(150, 658);
    enemyShip.center = CGPointMake(175, 20);
    missile.center = CGPointMake(playerShip.center.x, playerShip.center.y);

}

-(IBAction)startGame:(id)sender {

    // Hide buttons
    startButton.hidden = YES;
    exitButton.hidden = YES;

    // Images to show
    playerShip.hidden = NO;
    enemyShip.hidden = NO;
    earth.hidden = NO;

    // Labels
    scoreLabel.hidden = NO;
    livesLabel.hidden = NO;

    [self positionEnemy];

}

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

}

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {

    touch = [touches anyObject];
    CGPoint point = [touch locationInView:self.view];

    playerShip.center = CGPointMake(point.x, playerShip.center.y);

}

-(void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    [missileMovementTimer invalidate];
    missile.hidden = NO;
    missile.center = CGPointMake(playerShip.center.x, playerShip.center.y);

    missileMovementTimer = [NSTimer scheduledTimerWithTimeInterval:0.01 target:self selector:@selector(missileMovement) userInfo:nil repeats:YES];

}

-(void)positionEnemy {

    // Random enemy position
    enemyPosition = arc4random() % 249;
    enemyPosition = enemyPosition + 20;

    // Enemy Image Location
    enemyShip.center = CGPointMake(enemyPosition, -40);

    // Set enemy speed
    randomSpeed = arc4random() % 3;
    switch (randomSpeed) {
        case 0:
            enemySpeed = 0.03;
            break;
        case 1:
            enemySpeed = 0.02;
            break;
        case 2:
            enemySpeed = 0.01;

        default:
            break;
    }

    enemyAttackOccurence = arc4random() % 5;
    [self performSelector:@selector(enemyMovementTimerMethod) withObject:nil afterDelay:enemyAttackOccurence];

}

-(void)enemyMovementTimerMethod {

    enemyMovementTimer = [NSTimer scheduledTimerWithTimeInterval:enemySpeed target:self selector:@selector(enemyMovement) userInfo:nil repeats:YES];


}

-(void)enemyMovement {

    enemyShip.center = CGPointMake(enemyShip.center.x, enemyShip.center.y + 2);

    if (CGRectIntersectsRect(enemyShip.frame, earth.frame)) {

        lives = lives - 1;
        liveString = [NSString stringWithFormat:@"Lives: %i", lives];
        livesLabel.text = liveString;

        // Stop Enemy Moving
        [enemyMovementTimer invalidate];

        if (lives > 0) {
            [self positionEnemy];
        }
        if (lives == 0) {
            [self gameOver];
        }

    }

}

-(void)missileMovement {

    missile.hidden = NO;
    missile.center = CGPointMake(missile.center.x, missile.center.y - 2);

    if (CGRectIntersectsRect(missile.frame, enemyShip.frame)) {
        score = score + 1;
        scoreString = [NSString stringWithFormat:@"Score: %i", score];
        scoreLabel.text = scoreString;
        // Stop missile
        [missileMovementTimer invalidate];
        // Position missile to be at the playerShip's center
        missile.center = CGPointMake(playerShip.center.x, playerShip.center.y);
        missile.hidden = YES;
        // Stop enemy movement
        [enemyMovementTimer invalidate];
        [self positionEnemy];
    }

}

-(void)gameOver {

    [enemyMovementTimer invalidate];
    [missileMovementTimer invalidate];
    [self performSelector:@selector(gameReplay) withObject:nil afterDelay:3];

}

-(void) gameReplay {

    // Images that are to be hidden
    playerShip.hidden = YES;
    enemyShip.hidden = YES;
    missile.hidden = YES;
    earth.hidden = YES;

    // Hidden Labels
    scoreLabel.hidden = YES;
    livesLabel.hidden = YES;

    // Set score and lives remaining
    score = 0;
    lives = 0;

    // Strings
    scoreString = [NSString stringWithFormat:@"Score: 0"];
    liveString = [NSString stringWithFormat:@"Lives: 0"];

    // Initial Label Text
    scoreLabel.text = scoreString;
    livesLabel.text = liveString;

    // Image starting positions
    playerShip.center = CGPointMake(150, 658);
    enemyShip.center = CGPointMake(175, 20);
    missile.center = CGPointMake(playerShip.center.x, playerShip.center.y);

}

@end

#导入“ViewController.h”
@界面视图控制器（）
@结束
智力得分；
int生命；
内部攻击发生；
灌肠位；
int随机速度；
漂浮敌人的速度；
@实现视图控制器
-（无效）viewDidLoad{
[超级视图下载]；
//加载视图后，通常从nib执行任何其他设置。
}
-（无效）未收到记忆警告{
[超级记忆警告]；
//处置所有可以重新创建的资源。
}
@结束
@PlayViewController的实现
-（无效）视图显示：（BOOL）动画{
//要隐藏的图像
playerShip.hidden=是；
Enemmyship.hidden=是；
导弹隐藏=是；
earth.hidden=是；
//隐藏标签
scoreLabel.hidden=是；
livesLabel.hidden=是；
//设定分数和剩余生命
得分=0；
寿命=0；
//弦
scoreString=[NSString stringWithFormat:@“分数：0”]；
liveString=[NSString stringWithFormat:@“生命：0”]；
//初始标签文本
scoreLabel.text=scoreString；
livesLabel.text=liveString；
//图像起始位置
playerShip.center=CGPointMake（150658）；
enemyShip.center=CGPointMake（175,20）；
employee.center=CGPointMake（playerShip.center.x，playerShip.center.y）；
}
-（iAction）开始名称：（id）发送方{
//隐藏按钮
startButton.hidden=是；
exitButton.hidden=是；
//要显示的图像
playerShip.hidden=否；
Enemmyship.hidden=否；
earth.hidden=否；
//标签
scoreLabel.hidden=否；
livesLabel.hidden=否；
[敌我]；
}
-（无效）触摸开始：（NSSet*）触摸事件：（UIEvent*）事件{
}
-（无效）触摸移动：（NSSet*）触摸事件：（UIEvent*）事件{
touch=[触摸任何对象]；
CGPoint=[触摸位置视图：self.view]；
playerShip.center=CGPointMake（point.x，playerShip.center.y）；
}
-（void）touchesend:（NSSet*）toucheevent:（UIEvent*）event{
[任务移动计时器失效]；
导弹隐藏=否；
employee.center=CGPointMake（playerShip.center.x，playerShip.center.y）；
missileMovementTimer=[NSTimer scheduledTimerWithTimeInterval:0.01目标：自选择器：@selector（missileMovement）用户信息：无重复：是]；
}
-（无效）敌方{
//随机敌方阵地
enemyPosition=arc4random（）%249；
灌肠位置=灌肠位置+20；
//敌方图像定位
enemyShip.center=CGPointMake（enemyPosition，-40）；
//设定敌人的速度
randomSpeed=arc4random（）%3；
开关（随机速度）{
案例0：
敌人速度=0.03；
打破
案例1：
敌人速度=0.02；
打破
案例2：
敌人速度=0.01；
违约：
打破
}
EnemyAttackOccurrence=arc4random（）%5；
[自执行选择器：@selector（enemyMovementTimerMethod），对象：nil afterDelay:enemyattackoccurrence]；
}
-（无效）enemyMovementTimerMethod{
enemyMovementTimer=[NSTimer scheduledTimerWithTimeInterval:enemySpeed target:self self selector:@selector（enemyMovement）userInfo:nil repeats:YES]；
}
-（无效）灌肠运动{
enemyShip.center=CGPointMake（enemyShip.center.x，enemyShip.center.y+2）；
if（CGRectIntersectsRect（enemyShip.frame，earth.frame））{
生命=生命-1；
liveString=[NSString stringWithFormat:@“生命：%i”，生命]；
livesLabel.text=liveString；
//阻止敌人移动
[enemyMovementTimer失效]；
如果（寿命>0）{
[敌我]；
}
如果（寿命==0）{
[自我放逐]；
}
}
}
-（无效）文书动议{
导弹隐藏=否；
emilose.center=CGPointMake（emilose.center.x，emilose.center.y-2）；
if（CGRectIntersectsRect（emilose.frame，enemyShip.frame））{
分数=分数+1；
scoreString=[NSString stringWithFormat:@“分数：%i”，分数]；
scoreLabel.text=scoreString；
//拦截导弹
[任务移动计时器失效]；
//将导弹定位在玩家中心
employee.center=CGPointMake（playerShip.center.x，playerShip.center.y）；
导弹隐藏=是；
//阻止敌人移动
[enemyMovementTimer失效]；
[敌我]；
}
}
-（无效）游戏结束{
[enemyMovementTimer失效]；
[任务移动计时器失效]；
[自执行选择器：@selector（gameReplay）with object:nil afterDelay:3]；
}
-（无效）游戏重播{
//要隐藏的图像
playerShip.hidden=是；
Enemmyship.hidden=是；
导弹隐藏=是；
earth.hidden=是；
//隐藏标签
scoreLabel.hidden=是；
livesLabel.hidden=是；
//设定分数和剩余生命
得分=0；
寿命=0；
//弦
scoreString=[NSString stringWithFormat:@“分数：0”]；
liveString=[NSString stringWithFormat:@“生命：0”]；
//初始标签文本
scoreLabel.text=scoreString；
livesLabel.text=liveString；
//图像起始位置
playerShip.center=CGPointMake（150658）；
enemyShip.center=CGPointMake（175,20）；
employee.center=CGPointMake（playerShip.center.x，playerShip.center.y）；
}
@结束

ViewController.h（仅用于备份）

#导入
@界面ViewController:UIViewController{
IBUIButton*StartName；
}
@结束
@界面PlayViewController:UIViewController{
IBUIImageView*剧组；
IBUIImageView*电子商务；
IBUIImageView*导弹；
IBUIImageView*地球；
ibuilabel*livesLabel；
IBUILabel*s
#import <UIKit/UIKit.h>

@interface ViewController : UIViewController {

    IBOutlet UIButton *startGame;

}

@end
@interface PlayViewController : UIViewController {

    IBOutlet UIImageView *playerShip;
    IBOutlet UIImageView *enemyShip;
    IBOutlet UIImageView *missile;
    IBOutlet UIImageView *earth;

    IBOutlet UILabel *livesLabel;
    IBOutlet UILabel *scoreLabel;

    IBOutlet UIButton *startButton;
    IBOutlet UIButton *exitButton;

    UITouch *touch;

    NSString *liveString;
    NSString *scoreString;

    NSTimer *enemyMovementTimer;
    NSTimer *missileMovementTimer;

}

-(IBAction)startGame:(id)sender;

@end