MVC-Apple
原生的MVC
iOS中最常用的架构
提到MVC 就不能不说 UITableView
这里是创建model 创建view 给view复值都是在Controller中
响应事件是从 C ->view的
这里重点说下MVC的缺点
控制器中的代码非常冗余
看下代码
- (void)viewDidLoad {
[super viewDidLoad];
// [self loadNewsData];
[self loadShopData];
}
- (void)loadShopData
{
self.shopData = [NSMutableArray array];
for (int i = 0; i < 20; i++) {
MJShop *shop = [[MJShop alloc] init];
shop.name = [NSString stringWithFormat:@"商品-%d", i];
shop.price = [NSString stringWithFormat:@"¥19.%d", i];
[self.shopData addObject:shop];
}
}
- (void)loadNewsData
{
self.newsData = [NSMutableArray array];
for (int i = 0; i < 20; i++) {
MJNews *news = [[MJNews alloc] init];
news.title = [NSString stringWithFormat:@"news-title-%d", i];
news.content = [NSString stringWithFormat:@"news-content-%d", i];
[self.newsData addObject:news];
}
}
#pragma mark - Table view data source
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return self.shopData.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"NewsCell" forIndexPath:indexPath];
MJShop *shop = self.shopData[indexPath.row];
cell.detailTextLabel.text = shop.price;
cell.textLabel.text = shop.name;
return cell;
}
#pragma mark - UITableViewDelegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
NSLog(@"1111");
}
MVC-变种
主要是在C中创建model 和 view 将model传到view
view响应事件 并传到C中 view -> C
- (void)viewDidLoad {
[super viewDidLoad];
// 创建view
MJAppView *appView = [[MJAppView alloc] init];
appView.frame = CGRectMake(100, 100, 100, 150);
appView.delegate = self;
[self.view addSubview:appView];
// 加载模型数据
MJApp *app = [[MJApp alloc] init];
app.name = @"QQ";
app.image = @"QQ";
// 设置数据到view上
appView.app = app;
// appView.iconView.image = [UIImage imageNamed:app.image];
// appView.nameLabel.text = app.name;
}
#pragma mark - MJAppViewDelegate
- (void)appViewDidClick:(MJAppView *)appView
{
NSLog(@"控制器监听到了appView的点击");
}
MVP
创建一个中间层的Presenter
在Presenter中创建view model 实现数据的展示
代码展示下 大家就都明白了
- (void)viewDidLoad {
[super viewDidLoad];
self.presenter = [[MJAppPresenter alloc] initWithController:self];
}
- (instancetype)initWithController:(UIViewController *)controller
{
if (self = [super init]) {
self.controller = controller;
// 创建View
MJAppView *appView = [[MJAppView alloc] init];
appView.frame = CGRectMake(100, 100, 100, 150);
appView.delegate = self;
[controller.view addSubview:appView];
// 加载模型数据
MJApp *app = [[MJApp alloc] init];
app.name = @"QQ";
app.image = @"QQ";
// 赋值数据
[appView setName:app.name andImage:app.image];
// appView.iconView.image = [UIImage imageNamed:app.image];
// appView.nameLabel.text = app.name;
}
return self;
}
#pragma mark - MJAppViewDelegate
- (void)appViewDidClick:(MJAppView *)appView
{
NSLog(@"presenter 监听了 appView 的点击");
}
MVP与MVC区别:
作为一种新的模式,MVP与MVC有着一个重大的区别:在MVP中View并不直接使用Model,它们之间的通信是通过Presenter (MVC中的Controller)来进行的,所有的交互都发生在Presenter内部,而在MVC中View会直接从Model中读取数据而不是通过 Controller。
在MVC里,View是可以直接访问Model的!从而,View里会包含Model信息,不可避免的还要包括一些业务逻辑。 在MVC模型里,更关注的Model的改变,而同时有多个对Model的不同显示,即View。所以,在MVC模型里,Model不依赖于View,但是View是依赖于Model的。不仅如此,因为有一些业务逻辑在View里实现了,导致要更改View也是比较困难的,至少那些业务逻辑是无法重用的。
虽然 MVC 中的 View 的确“可以”访问 Model,但是我们不建议在 View 中依赖 Model,而是要求尽可能把所有业务逻辑都放在 Controller 中处理,而 View 只和 Controller 交互。
区别如下图所示:
3.MVVM框架
MVVM主要是对MVP中数据的处理进行了优化,可以使用KVO、RAC、FBKVOController等方法检测数据的改变 从来传值
干代码
viewModel中的代码
- (instancetype)initWithController:(UIViewController *)controller
{
if (self = [super init]) {
self.controller = controller;
// 创建View
MJAppView *appView = [[MJAppView alloc] init];
appView.frame = CGRectMake(100, 100, 100, 150);
appView.delegate = self;
appView.viewModel = self;
[controller.view addSubview:appView];
// 加载模型数据
MJApp *app = [[MJApp alloc] init];
app.name = @"QQ";
app.image = @"QQ";
// 设置数据
self.name = app.name;
self.image = app.image;
}
return self;
}
#pragma mark - MJAppViewDelegate
- (void)appViewDidClick:(MJAppView *)appView
{
NSLog(@"viewModel 监听了 appView 的点击");
}
view中的代码
- (instancetype)initWithFrame:(CGRect)frame
{
if (self = [super initWithFrame:frame]) {
UIImageView *iconView = [[UIImageView alloc] init];
iconView.frame = CGRectMake(0, 0, 100, 100);
[self addSubview:iconView];
_iconView = iconView;
UILabel *nameLabel = [[UILabel alloc] init];
nameLabel.frame = CGRectMake(0, 100, 100, 30);
nameLabel.textAlignment = NSTextAlignmentCenter;
[self addSubview:nameLabel];
_nameLabel = nameLabel;
}
return self;
}
- (void)setViewModel:(MJAppViewModel *)viewModel
{
_viewModel = viewModel;
__weak typeof(self) waekSelf = self;
[self.KVOController observe:viewModel keyPath:@"name" options:NSKeyValueObservingOptionNew block:^(id _Nullable observer, id _Nonnull object, NSDictionary<NSKeyValueChangeKey,id> * _Nonnull change) {
waekSelf.nameLabel.text = change[NSKeyValueChangeNewKey];
}];
[self.KVOController observe:viewModel keyPath:@"image" options:NSKeyValueObservingOptionNew block:^(id _Nullable observer, id _Nonnull object, NSDictionary<NSKeyValueChangeKey,id> * _Nonnull change) {
waekSelf.iconView.image = [UIImage imageNamed:change[NSKeyValueChangeNewKey]];
}];
}
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
if ([self.delegate respondsToSelector:@selector(appViewDidClick:)]) {
[self.delegate appViewDidClick:self];
}
}
MVVM与MVP区别:
mvvm模式将Presener改名为View Model,基本上与MVP模式完全一致,唯一的区别是,它采用双向绑定(data-binding): View的 变动,自动反映在View Model,反之亦然。这样开发者就不用处理接收事件和View更新的工作,框架已经帮你做好了。
MVC、MVP、MVVM模式的概念与区别
感谢 小马哥 的视频 播客