MVVM.png

Controller

#import "ViewController.h"
#import "MJAppViewModel.h"

@interface ViewController ()
@property (strong, nonatomic) MJAppViewModel *viewModel;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.viewModel = [[MJAppViewModel alloc] initWithController:self];
}

@end

ViewModel

#import "MJAppViewModel.h"
#import "MJApp.h"
#import "MJAppView.h"

@interface MJAppViewModel() <MJAppViewDelegate>
@property (weak, nonatomic) UIViewController *controller;
@property (copy, nonatomic) NSString *name;
@property (copy, nonatomic) NSString *image;
@end

@implementation MJAppViewModel

- (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");
}

@end

View .h

#import <UIKit/UIKit.h>

@class MJAppView, MJAppViewModel;

@protocol MJAppViewDelegate <NSObject>
@optional
- (void)appViewDidClick:(MJAppView *)appView;
@end

@interface MJAppView : UIView
@property (weak, nonatomic) MJAppViewModel *viewModel;
@property (weak, nonatomic) id<MJAppViewDelegate> delegate;
@end

View .m

#import "MJAppView.h"
#import "NSObject+FBKVOController.h"

@interface MJAppView()
@property (weak, nonatomic) UIImageView *iconView;
@property (weak, nonatomic) UILabel *nameLabel;
@end

@implementation MJAppView

- (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];
    }
}

@end

Model

@interface MJApp : NSObject
@property (copy, nonatomic) NSString *name;
@property (copy, nonatomic) NSString *image;
@end