加載 info.plist文件

#import "ViewController.h"

@interface ViewController ()
/** 存放全部商品的總體 */
@property (weak, nonatomic) IBOutlet UIView *shopsView;

/** HUD */
@property (weak, nonatomic) IBOutlet UILabel *hud;

// 文檔註釋
/** 添加按鈕 */
@property (weak, nonatomic) UIButton *addBtn;
/** 刪除按鈕 */
@property (weak, nonatomic) UIButton *removeBtn;

/** 所有商品數據 */
@property (strong, nonatomic) NSArray *shops;
@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    
    // 添加「添加按鈕」
    self.addBtn = [self addButtonWithImage:@"add" highImage:@"add_highlighted" disableImage:@"add_disabled" frame:CGRectMake(30, 30, 50, 50) action:@selector(add)];
    
    // 添加「刪除按鈕」
    self.removeBtn = [self addButtonWithImage:@"remove" highImage:@"remove_highlighted" disableImage:@"remove_disabled" frame:CGRectMake(270, 30, 50, 50) action:@selector(remove)];
    self.removeBtn.enabled = NO;
    
    // 加載plist數據
    
    // 一個NSBundle對象對應一個資源包（圖片、音頻、視頻、plis等文件）
    // NSBundle的做用：用來訪問與之對應的資源包內部的文件，能夠用來得到文件的全路徑
    // 項目中添加的資源都會被添加到主資源包中
    // [NSBundle mainBundle]關聯的就是項目的主資源包
    NSBundle *bundle = [NSBundle mainBundle];
    
    // 利用mainBundle得到plist文件在主資源包中的全路徑
    NSString *file = [bundle pathForResource:@"shops" ofType:@"plist"];
//    NSString *file = [bundle pathForResource:@"shops.plist" ofType:nil];
    
    // 凡是參數名爲File，傳遞的都是文件的全路徑
    self.shops = [NSArray arrayWithContentsOfFile:file];
}

#pragma mark 添加按鈕
- (UIButton *)addButtonWithImage:(NSString *)image highImage:(NSString *)highImage disableImage:(NSString *)disableImage frame:(CGRect)frame action:(SEL)action
{
    // 建立按鈕
    UIButton *btn = [[UIButton alloc] init];
    // 設置背景圖片
    [btn setBackgroundImage:[UIImage imageNamed:image] forState:UIControlStateNormal];
    [btn setBackgroundImage:[UIImage imageNamed:highImage] forState:UIControlStateHighlighted];
    [btn setBackgroundImage:[UIImage imageNamed:disableImage] forState:UIControlStateDisabled];
    // 設置位置和尺寸
    btn.frame = frame;
    // 監聽按鈕點擊
    [btn addTarget:self action:action forControlEvents:UIControlEventTouchUpInside];
    // 添加按鈕
    [self.view addSubview:btn];
    return btn;
}

#pragma mark 添加
- (void)add
{
//    self.shopsView.clipsToBounds = YES;
    
    // 每個商品的尺寸
    CGFloat shopW = 80;
    CGFloat shopH = 90;
    
    // 一行的列數
    int cols = 3;
    
    // 每一列之間的間距
    CGFloat colMargin = (self.shopsView.frame.size.width - cols * shopW) / (cols - 1);
    // 每一行之間的間距
    CGFloat rowMargin = 10;
    
    // 建立一個父控件（總體：存放圖片和文字）
    UIView *shopView = [[UIView alloc] init];
    shopView.backgroundColor = [UIColor redColor];
    
    // 商品的索引
    NSUInteger index = self.shopsView.subviews.count;
    
    // 商品的x值
    NSUInteger col = index % cols;
    CGFloat shopX = col * (shopW + colMargin);
    
    // 商品的y值
    NSUInteger row = index / cols;
    CGFloat shopY = row * (shopH + rowMargin);
    
    shopView.frame = CGRectMake(shopX, shopY, shopW, shopH);
    [self.shopsView addSubview:shopView];
    
    // 得到index位置對應的商品數據
    NSDictionary *shop = self.shops[index];
    
    // 添加圖片
    UIImageView *iconView = [[UIImageView alloc] init];
    iconView.image = [UIImage imageNamed:shop[@"icon"]];
    iconView.frame = CGRectMake(0, 0, shopW, shopW);
    iconView.backgroundColor = [UIColor blueColor];
    [shopView addSubview:iconView];
    
    // 添加文字
    UILabel *label = [[UILabel alloc] init];
    label.text = shop[@"name"];
    label.frame = CGRectMake(0, shopW, shopW, shopH - shopW);
    label.font = [UIFont systemFontOfSize:11];
    label.textAlignment = NSTextAlignmentCenter;
    [shopView addSubview:label];
    
    // 控制按鈕的可用性
    [self checkState];
}

#pragma mark 刪除
- (void)remove
{
    [[self.shopsView.subviews lastObject] removeFromSuperview];
    
    // 控制按鈕的可用性
    [self checkState];
}

#pragma mark 檢查狀態：按鈕狀態
- (void)checkState
{
    // 刪除按鈕何時能夠點擊：商品個數 > 0
    self.removeBtn.enabled = (self.shopsView.subviews.count > 0);
    // 添加按鈕何時能夠點擊：商品個數 < 總數
    self.addBtn.enabled = (self.shopsView.subviews.count < self.shops.count);
    
    // 顯示HUD
    NSString *text = nil;
    if (self.removeBtn.enabled == NO) { // 刪光了
        text = @"已經所有刪除";
    } else if (self.addBtn.enabled == NO) { // 加滿了
        text = @"已經添加滿了";
    }
    if (text == nil) return;
    
    self.hud.text = text;
    self.hud.alpha = 1.0;
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        self.hud.alpha = 0.0;
    });
}

@end