iOS开发UI篇—从代码的逐步优化看MVC

iOS开发UI篇—从代码的逐步优化看MVC

一、要求

要求完成下面一个小的应用程序。

 

二、一步步对代码进行优化

注意:在开发过程中,优化的过程是一步一步进行的。(如果一个人要吃五个包子才能吃饱,那么他是否直接吃第五个,前面四个不用吃就饱了?)

1.完成基本要求的代码(使用了字典转模型和xib连线)

(1)文件结构

(2)主要代码

  字典转模型部分:

 YYappInfo.h头文件

 1 //
 2 //  YYappInfo.h
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import <Foundation/Foundation.h>
10 
11 @interface YYappInfo : NSObject
12 @property(nonatomic,copy)NSString *name;
13 @property(nonatomic,copy)NSString *icon;
14 @property(nonatomic,strong,readonly)UIImage *img;
15 
16 -(instancetype)initWithDict:(NSDictionary *)dict;
17 /**工厂方法*/
18 +(instancetype)appInfoWithDict:(NSDictionary *)dict;
19 @end

YYappInfo.m文件

 1 //
 2 //  YYappInfo.m
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import "YYappInfo.h"
10 @interface YYappInfo()
11 {
12     UIImage *_img;
13 }
14 @end
15 @implementation YYappInfo
16 -(instancetype)initWithDict:(NSDictionary *)dict
17 {
18     if (self=[super init]) {
19         self.name=dict[@"name"];
20         self.icon=dict[@"icon"];
21     }
22     return self;
23 }
24 
25 +(instancetype)appInfoWithDict:(NSDictionary *)dict
26 {
27     return [[self alloc]initWithDict:dict];
28 }
29 
30 -(UIImage *)img
31 {
32     _img=[UIImage imageNamed:self.icon];
33     return _img;
34 }
35 @end

 xib部分(YYappInfoView.h文件):

注:(xib视图和YYappInfoView进行了关联,三个属性均进行了连线)  

 1 //
 2 //  YYappInfoView.h
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import <UIKit/UIKit.h>
10 
11 @interface YYappInfoView : UIView
12 @property (strong, nonatomic) IBOutlet UIImageView *appInfoViewimg;
13 
14 @property (strong ,nonatomic) IBOutlet UILabel *appInfoViewlab;
15 @property (strong, nonatomic) IBOutlet UIButton *appInfoViewbtn;
16 
17 @end

主要功能实现部分:

YYViewController.m文件

 1 //
 2 //  YYViewController.m
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import "YYViewController.h"
10 #import "YYappInfo.h"
11 #import "YYappInfoView.h"
12 
13 @interface YYViewController ()
14 @property(nonatomic,strong)NSArray *apps;
15 @end
16 
17 //开发思路
18 //1.加载plist文件(字典转模型提供接口)
19 //2.使用xib文件完成单个的view
20 //3.计算坐标,使用for循环把view展现到界面上
21 //4.优化代码
22 @implementation YYViewController
23 
24 //get方法,懒加载
25 -(NSArray *)apps
26 {
27     if (!_apps) {
28         NSString *path = [[NSBundle mainBundle]pathForResource:@"app.plist" ofType:nil];
29         NSArray * arrayM = [NSArray arrayWithContentsOfFile:path];
30         
31         NSMutableArray *appinfoarray=[NSMutableArray array];
32         for (NSDictionary *dict in arrayM) {
33             [appinfoarray addObject:[YYappInfo appInfoWithDict:dict]];
34         }
35         _apps = appinfoarray;
36     }
37     return _apps;
38 }
39 
40 - (void)viewDidLoad
41 {
42     [super viewDidLoad];
43     NSLog(@"%d",self.apps.count);
44     
45     int totalloc = 3;
46     CGFloat appviewW = 80;
47     CGFloat appviewH = 90;
48     CGFloat margin = (self.view.frame.size.width-totalloc*appviewW)/(totalloc+1);
49     
50     int count=self.apps.count;
51     for (int i = 0; i < count; i++) {
52         int row = i/totalloc;
53         int loc = i%totalloc;
54         
55         CGFloat appviewX = margin + (margin + appviewW) * loc;
56         CGFloat appviewY =  margin + (margin + appviewH) * row;
57         
58           YYappInfo *appinfo=self.apps[i];
59         
60         //拿出xib中的数据
61         NSArray *arryM=[[NSBundle mainBundle]loadNibNamed:@"appInfoxib" owner:nil options:nil];
62         YYappInfoView *appinfoview=[arryM firstObject];
63         //设置位置
64         appinfoview.frame=CGRectMake(appviewX, appviewY, appviewW, appviewH);
65         //设置值
66         appinfoview.appInfoViewimg.image=appinfo.img;
67         appinfoview.appInfoViewlab.text=appinfo.name;
68         //添加到视图
69         appinfoview.appInfoViewbtn.tag=i;
70         [appinfoview.appInfoViewbtn addTarget:self action:@selector(Click:) forControlEvents:UIControlEventTouchUpInside];
71         [self.view addSubview:appinfoview];
72     }
73 }
74 -(void)Click:(UIButton *)btn
75 {
76     btn.enabled=NO;
77     YYappInfo *appinfo=self.apps[btn.tag];
78     UILabel *lab=[[UILabel alloc]initWithFrame:CGRectMake(60, 450, 200, 20)];
79     [lab setBackgroundColor:[UIColor lightGrayColor]];
80     [lab setTextAlignment:NSTextAlignmentCenter];
81     [lab setText:[NSString stringWithFormat:@"%@成功下载",appinfo.name]];
82     [self.view addSubview:lab];
83     
84     lab.alpha=1.0;
85     [UIView animateWithDuration:2.0 animations:^{
86         lab.alpha=0;
87     }completion:^(BOOL finished) {
88         [lab removeFromSuperview];
89     }];
90 }
91 @end

2.对1进行优化(把数据呈现部分封装到视图)

说明:在1的基础上寻找还会有那些可以优化的部分

1)改进思路:

(1)1中主文件的66~67行对控件属性的设置能否拿到视图中进行?

(2)1中61~62行是从xib文件中读取信息的操作,且和主控制器没有什么太大的关联,能否把它也封装到视图中进行?

(3)当上述两个步骤完成后,主文件69行以后的按钮操作和按钮单击事件就显得很突兀,放在主控制器中已经不再合适,是否可以把它放到视图中进行处理

2)按照上述思路优化后的代码如下:

  优化视图,在视图部分之对外提供一个接口,把数据的处理封装在内部

YYappInfoView.h文件代码:

 1 //
 2 //  YYappInfoView.h
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import <UIKit/UIKit.h>
10 @class YYappInfo;
11 @interface YYappInfoView : UIView
12 
13 //读取
14 //+(instancetype)appInfoView;
15 //只对外开放一个数据接口
16 +(instancetype)appInfoViewWithappInfo:(YYappInfo *)appinfo;
17 @end

YYappInfoView.m文件代码

说明:该文件中的属性和click等均已做了连线的操作。

 1 //
 2 //  YYappInfoView.m
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import "YYappInfoView.h"
10 #import "YYappInfo.h"
11 //私有扩展,把属性拿进来
12 @interface YYappInfoView ()
13 @property (strong, nonatomic) IBOutlet UIImageView *appInfoViewimg;
14 @property (strong ,nonatomic) IBOutlet UILabel *appInfoViewlab;
15 @property (strong, nonatomic) IBOutlet UIButton *appInfoViewbtn;
16 @property(strong,nonatomic)YYappInfo *appinfo;
17 
18 @end
19 @implementation YYappInfoView
20 
21 +(instancetype)appInfoView
22 {
23     NSArray *arryM=[[NSBundle mainBundle]loadNibNamed:@"appInfoxib" owner:nil options:nil];
24     YYappInfoView *appinfoview=[arryM firstObject];
25     return appinfoview;
26 }
27 
28 +(instancetype)appInfoViewWithappInfo:(YYappInfo *)appinfo
29 {
30     YYappInfoView *appInfoView=[self appInfoView];
31     appInfoView.appinfo=appinfo;
32     return appInfoView;
33 }
34 
35 -(void)setAppinfo:(YYappInfo *)appinfoc
36 {
37     //这里一定要记录变化
38     _appinfo=appinfoc;
39     self.appInfoViewimg.image=appinfoc.img;
    self.appInfoViewlab.text=appinfoc.name;
41 }
42 - (IBAction)Click {
43     
44     self.appInfoViewbtn.enabled=NO;
45     //YYappInfo *appinfo=self.apps[];
46     
47     YYappInfo *appinfo=self.appinfo;
48     UILabel *lab=[[UILabel alloc]initWithFrame:CGRectMake(60, 450, 200, 20)];
49     [lab setBackgroundColor:[UIColor lightGrayColor]];
50     [lab setTextAlignment:NSTextAlignmentCenter];
51     [lab setText:[NSString stringWithFormat:@"%@成功下载",appinfo.name]];
52     //把lab添加到父视图(即view中)
53     [self.superview addSubview:lab];
54     
55     lab.alpha=1.0;
56     [UIView animateWithDuration:2.0 animations:^{
57         lab.alpha=0;
58     }completion:^(BOOL finished) {
59         [lab removeFromSuperview];
60     }];
61 }
62 
63 
64 @end

优化后的主控制器部分

YYViewController.m文件代码

 1 //
 2 //  YYViewController.m
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import "YYViewController.h"
10 #import "YYappInfo.h"
11 #import "YYappInfoView.h"
12 
13 @interface YYViewController ()
14 @property(nonatomic,strong)NSArray *apps;
15 @end
16 @implementation YYViewController
17 
18 -(NSArray *)apps
19 {
20     if (!_apps) {
21         NSString *path = [[NSBundle mainBundle]pathForResource:@"app.plist" ofType:nil];
22         NSArray * arrayM = [NSArray arrayWithContentsOfFile:path];
23         
24         NSMutableArray *appinfoarray=[NSMutableArray array];
25         for (NSDictionary *dict in arrayM) {
26             [appinfoarray addObject:[YYappInfo appInfoWithDict:dict]];
27         }
28         _apps = appinfoarray;
29     }
30     return _apps;
31 }
32 
33 - (void)viewDidLoad
34 {
35     [super viewDidLoad];
36     NSLog(@"%d",self.apps.count);
37     
38     int totalloc = 3;
39     CGFloat appviewW = 80;
40     CGFloat appviewH = 90;
41     CGFloat margin = (self.view.frame.size.width-totalloc*appviewW)/(totalloc+1);
42     
43     int count=self.apps.count;
44     for (int i = 0; i < count; i++) {
45         int row = i/totalloc;
46         int loc = i%totalloc;
47         
48         CGFloat appviewX = margin + (margin + appviewW) * loc;
49         CGFloat appviewY =  margin + (margin + appviewH) * row;
50         
51         /*思路:
52          要达到的效果 appinfoview.appinfo=appinfo;
53         优化后即变成  appinfoview.appinfo=self.apps[i];
54         要进行上面代码的操作,需要在视图中新增加一个appinfo类的属性,这样数据——》视图的转换即可以不需要在主控制器中完成,让程序结构一目了然
55          */
56         YYappInfo *appinfo=self.apps[i];
57         YYappInfoView *appinfoview=[YYappInfoView appInfoViewWithappInfo:appinfo];
58         //设置位置
59         appinfoview.frame=CGRectMake(appviewX, appviewY, appviewW, appviewH);
60         //添加
61         [self.view addSubview:appinfoview];
62     }
63 }
64 @end

3.对2进一步优化(把数据处理部分拿到模型中去进行)

(1)思路:把字典转模型部分的数据处理操作,拿到模型中去处理,这样外界不需要再关心数据处理的内部细节。

(2)优化后的代码如下

YYappInfo.h文件中向外开放一个接口,返回一个处理好的数组。

 1 //
 2 //  YYappInfo.h
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import <Foundation/Foundation.h>
10 
11 @interface YYappInfo : NSObject
12 @property(nonatomic,copy)NSString *name;
13 @property(nonatomic,copy)NSString *icon;
14 @property(nonatomic,strong)UIImage *img;
15 
16 -(instancetype)initWithDict:(NSDictionary *)dict;
17 /**工厂方法*/
18 +(instancetype)appInfoWithDict:(NSDictionary *)dict;
19 +(NSArray *)appinfoarray;
20 @end

YYappInfo.m文件中的数据处理

 1 //
 2 //  YYappInfo.m
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import "YYappInfo.h"
10 @interface YYappInfo()
11 @end
12 @implementation YYappInfo
13 -(instancetype)initWithDict:(NSDictionary *)dict
14 {
15     if (self=[super init]) {
16         self.name=dict[@"name"];
17         self.icon=dict[@"icon"];
18     }
19     return self;
20 }
21 
22 +(instancetype)appInfoWithDict:(NSDictionary *)dict
23 {
24     return [[self alloc]initWithDict:dict];
25 }
26 
27 -(UIImage *)img
28 {
29     _img=[UIImage imageNamed:self.icon];
30     return _img;
31 }
32 
33 //把数据处理部分拿到模型中来处理
34 +(NSArray *)appinfoarray
35 {
36     NSString *path = [[NSBundle mainBundle]pathForResource:@"app.plist" ofType:nil];
37     NSArray * arrayM = [NSArray arrayWithContentsOfFile:path];
38     
39     NSMutableArray *appinfoarray=[NSMutableArray array];
40     for (NSDictionary *dict in arrayM) {
41         [appinfoarray addObject:[YYappInfo appInfoWithDict:dict]];
42     }
43     return appinfoarray;
44 }
45 @end

主控制器中不再需要关心数据处理的内部细节

YYViewController.m文件现在只是负责模型和视图之间的协调工作了,怎么样?差不多了吧。

 1 //
 2 //  YYViewController.m
 3 //  12-视图改进(1)
 4 //
 5 //  Created by apple on 14-5-25.
 6 //  Copyright (c) 2014年 itcase. All rights reserved.
 7 //
 8 
 9 #import "YYViewController.h"
10 #import "YYappInfo.h"
11 #import "YYappInfoView.h"
12 
13 @interface YYViewController ()
14 @property(nonatomic,strong)NSArray *apps;
15 @end
16 @implementation YYViewController
17 
18 -(NSArray *)apps
19 {
20     if (!_apps) {
21         _apps=[YYappInfo appinfoarray];
22     }
23     return _apps;
24 }
25 
26 - (void)viewDidLoad
27 {
28     [super viewDidLoad];
29     
30     int totalloc = 3;
31     CGFloat appviewW = 80;
32     CGFloat appviewH = 90;
33     CGFloat margin = (self.view.frame.size.width-totalloc*appviewW)/(totalloc+1);
34     
35     int count=self.apps.count;
36     for (int i = 0; i < count; i++) {
37         
38         int row = i/totalloc;
39         int loc = i%totalloc;
40         
41         CGFloat appviewX = margin + (margin + appviewW) * loc;
42         CGFloat appviewY =  margin + (margin + appviewH) * row;
43         
44         YYappInfo *appinfo=self.apps[i];
45         YYappInfoView *appinfoview=[YYappInfoView appInfoViewWithappInfo:appinfo];
46         appinfoview.frame=CGRectMake(appviewX, appviewY, appviewW, appviewH);
47         [self.view addSubview:appinfoview];
48     }
49 }
50 @end

实现效果:

 

4.补充说明

 View的封装思路

(1) 如果一个view内部的子控件比较多,一般会考虑自定义一个view,把它内部子控件的创建屏蔽起来,不让外界关心

(2) 外界可以传入对应的模型数据给view,view拿到模型数据后给内部的子控件设置对应的数据

三、mvc机制简单说明

 

说明:

(1)在开发过程中,作为控制器处理的量级应该很轻,不该操心的不操心。协调好模型和视图就ok了,要学会当一个好老板。

(2)三个部分各司其职,数据模型只负责数据的处理,视图部分只负责把拿到的数据进行显示,两个部分都是被动的,等待着大管家控制器的调遣。

(3)在OC中,如果视图和数据模型之间有通道,那控制器是否处于失控状态呢?

posted on 2014-05-25 11:28  文顶顶  阅读(...)  评论(... 编辑 收藏

导航

统计