MVVM

MVVM是Model-View-ViewModel的简写。,MVVM就是MVC的扩展，把数据处理全放到ViewModel里进行处理

一个模块文件中，分别有ViewController,View,Model,ViewModel四个文件  其中控制器VC在ViewController里，重写的view放到View文件夹里，数据模型放到Model里

数据请求等一系列操作放到ViewModel里

首先在ViewModel里写一个MovieModel类

#import <Foundation/Foundation.h>

#import "MovieModel.h"

#import <UIKit/UIKit.h>

typedef void (^ReturnValueBlock) (id returnValue);

typedef void (^ErrorCodeBlock) (id errorCode);

@interface MovieViewModel : NSObject

@property (nonatomic,copy)ReturnValueBlock returnBlock;

@property (nonatomic,copy)ErrorCodeBlock errorBlock;

//获取电影数据

- (void)getMovieData;

//跳转到电影详情页

- (void)movieDetailWithPublicModel: (MovieModel *)movieModel WithViewController: (UIViewController *)superController;

@end

#import "MovieViewModel.h"

#import "NetworkService.h"

#import "MovieModel.h"

#import "MovieViewController.h"

@implementation MovieViewModel

- (void)getMovieData{

    [NetworkServicerequestWithURL:@"/v2/movie/coming_soon"params:nilsuccess:^(id result) {

        NSLog(@"%@",result);

        

        NSArray *subjects = result[@"subjects"];

        NSMutableArray *modelArr = [NSMutableArrayarrayWithCapacity:subjects.count];

        for (NSDictionary *subjectin subjects) {

            MovieModel *model = [[MovieModelalloc]init];

            model.movieName = subject[@"title"];

            model.year = subject[@"year"];

            NSString *urlStr = subject[@"images"][@"medium"];

            model.imageUrl = [NSURLURLWithString:urlStr];

            model.detailUrl = subject[@"alt"];

            [modelArr addObject:model];

        }

        _returnBlock(modelArr);

        

    } failure:^(NSError *error) {

         NSLog(@"%@",error);

        _errorBlock(error);

    }];

}

然后在VC调用的时候（可以写成类方法）

  MovieViewModel *viewModel = [[MovieViewModelalloc]init];

    viewModel.returnBlock = ^(id returnValue){

        

        tableView.dataSource = returnValue;

        [tableView reloadData];

    };

    viewModel.errorBlock = ^(id errorCode){

      

        NSLog(@"%@",errorCode);

    };

    

    [viewModel getMovieData];

    

也可以重写tableView,把一系列的tableView的代理方法写到本身里

一下是我自己写的一个collectionView 在VIewModel请求数据，在VC回调block，可以在block里直接把数据赋值，直接给collectionView.dataSource,然后reload

//

//  MeiziCollectionView.m

//  meizi

//

//  Created by 俊洋洋 on 16/7/8.

//  Copyright © 2016年俊洋洋. All rights reserved.

//

#import "MeiziCollectionView.h"

#import "meiziCollectionViewCell.h"

@interface MeiziCollectionView()<UICollectionViewDelegate,UICollectionViewDataSource,UICollectionViewDelegateFlowLayout>

@end

@implementation MeiziCollectionView

- (instancetype)initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout

{

    self = [superinitWithFrame:frame collectionViewLayout:layout];

    self.backgroundColor =[UIColorwhiteColor];

    self.dataSource =self;

    self.delegate =self;

    [selfregisterClass:[meiziCollectionViewCellclass] forCellWithReuseIdentifier:@"cellID"];

    return self;

}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section

{

    returnself.dataSourcea.count;

}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath

{

    meiziCollectionViewCell *cell = [meiziCollectionViewCellcellWithCollectionView:collectionViewAtIndexPath:indexPath];

    [cell setupUI];

    cell.backgroundColor = [UIColorcyanColor];

    cell.model = self.dataSourcea[indexPath.row];

    return cell;

}

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath

{

    returnCGSizeMake(SCREENWIDTH/2.0f-10,SCREENWIDTH/2.0f-10);

}

- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section

{

    returnUIEdgeInsetsMake(15,5, 0,5);

//    UIEdgeInsetsMake(<#CGFloat top#>, <#CGFloat left#>, <#CGFloat bottom#>, <#CGFloat right#>)

}

/*

// Only override drawRect: if you perform custom drawing.

// An empty implementation adversely affects performance during animation.

- (void)drawRect:(CGRect)rect {

    // Drawing code

}

*/

@end