ios14--购物车优化2
// // ViewController.m // 03-综合练习 // // Created by xiaomage on 15/12/28. // Copyright © 2015年 小码哥. All rights reserved. // #import "ViewController.h" @interface ViewController () // 购物车 @property (weak, nonatomic) IBOutlet UIView *shopCarView; // 添加按钮 @property (weak, nonatomic) IBOutlet UIButton *addButton; // 删除按钮 @property (weak, nonatomic) IBOutlet UIButton *removeButton; /** 数据数组 */ @property (nonatomic, strong) NSArray *dataArr; @end @implementation ViewController /** * 懒加载 1.作用: 1>用到的时候再加载 2>全局只会被加载一次 3>全局都可以使用 过程: 1.重写成员变量的get方法 2.在get方法中判断: 1>如果为空,加载数据 2>如果不为空,就直接返回数据 */ - (NSArray *)dataArr{ if (_dataArr == nil) { // 加载数据 self.dataArr = @[ @{@"name":@"单肩包", @"icon":@"danjianbao"}, @{@"name":@"钱包", @"icon":@"qianbao"}, @{@"name":@"链条包", @"icon":@"liantiaobao"}, @{@"name":@"手提包", @"icon":@"shoutibao"}, @{@"name":@"双肩包", @"icon":@"shuangjianbao"}, @{@"name":@"斜挎包", @"icon":@"xiekuabao"} ]; } return _dataArr; } // 初始化数据 - (void)viewDidLoad { [super viewDidLoad]; // NSArray<NSDictionary *> *dataArr = @[ // @{@"name":@"单肩包", @"icon":@"danjianbao"}, // @{@"name":@"钱包", @"icon":@"qianbao"}, // @{@"name":@"链条包", @"icon":@"liantiaobao"}, // @{@"name":@"手提包", @"icon":@"shoutibao"}, // @{@"name":@"双肩包", @"icon":@"shuangjianbao"}, // @{@"name":@"斜挎包", @"icon":@"xiekuabao"} // ]; // self.dataArr = dataArr; } /** * 添加到购物车 * * @param button 按钮 */ - (IBAction)add:(UIButton *)button { /***********************1.定义一些常量*****************************/ // 1.总列数 NSInteger allCols = 3; // 2.商品的宽度 和 高度 CGFloat width = 80; CGFloat height = 100; // 3.求出水平间距 和 垂直间距 CGFloat hMargin = (self.shopCarView.frame.size.width - allCols * width) / (allCols -1); CGFloat vMargin = (self.shopCarView.frame.size.height - 2 * height) / 1; // 4. 设置索引 NSInteger index = self.shopCarView.subviews.count; // 5.求出x值 CGFloat x = (hMargin + width) * (index % allCols); CGFloat y = (vMargin + height) * (index / allCols); /***********************2.创建一个商品*****************************/ // 1.创建商品的view UIView *shopView = [[UIView alloc] init]; // 2.设置frame shopView.frame = CGRectMake(x, y, width, height); // 3.设置背景颜色 shopView.backgroundColor = [UIColor greenColor]; // 4.添加到购物车 [self.shopCarView addSubview:shopView]; // 5.创建商品的UIImageView对象 UIImageView *iconView = [[UIImageView alloc] init]; iconView.frame = CGRectMake(0, 0, width, width); iconView.backgroundColor = [UIColor blueColor]; [shopView addSubview:iconView]; // 6.创建商品标题对象 UILabel *titleLabel = [[UILabel alloc] init]; titleLabel.frame = CGRectMake(0, width, width, height - width); titleLabel.backgroundColor = [UIColor yellowColor]; titleLabel.textAlignment = NSTextAlignmentCenter; // 居中 [shopView addSubview:titleLabel]; /***********************3.设置数据*****************************/ // 方式四 (数组 + 字典) /* NSArray<NSDictionary *> *dataArr = @[ @{@"name":@"单肩包", @"icon":@"danjianbao"}, @{@"name":@"钱包", @"icon":@"qianbao"}, @{@"name":@"链条包", @"icon":@"liantiaobao"}, @{@"name":@"手提包", @"icon":@"shoutibao"}, @{@"name":@"双肩包", @"icon":@"shuangjianbao"}, @{@"name":@"斜挎包", @"icon":@"xiekuabao"} ]; */ // 懒加载 /* if (self.dataArr == nil) { self.dataArr = @[ @{@"name":@"单肩包", @"icon":@"danjianbao"}, @{@"name":@"钱包", @"icon":@"qianbao"}, @{@"name":@"链条包", @"icon":@"liantiaobao"}, @{@"name":@"手提包", @"icon":@"shoutibao"}, @{@"name":@"双肩包", @"icon":@"shuangjianbao"}, @{@"name":@"斜挎包", @"icon":@"xiekuabao"} ]; } */ // 设置数据 NSDictionary *dict = self.dataArr[index];//调用get方法 iconView.image = [UIImage imageNamed:dict[@"icon"]]; titleLabel.text = dict[@"name"]; /***********************4.设置按钮的状态*****************************/ button.enabled = (index != 5); // 5.设置删除按钮的状态 self.removeButton.enabled = YES; } /** * 从购物车中删除 * * @param button 按钮 */ - (IBAction)remove:(UIButton *)button { // 1. 删除最后一个商品 UIView *lastShopView = [self.shopCarView.subviews lastObject]; [lastShopView removeFromSuperview]; // 3. 设置添加按钮的状态 self.addButton.enabled = YES; // 4. 设置删除按钮的状态 /* if (self.shopCarView.subviews.count == 0) { self.removeButton.enabled = NO; } */ self.removeButton.enabled = (self.shopCarView.subviews.count != 0); } @end 本文转自农夫山泉别墅博客园博客，原文链接：http://www.cnblogs.com/yaowen/p/7449679.html，如需转载请自行联系原作者
