[iOS基础控件 - 4.4] 进一步封装"APP列表”,初见MVC模式
A.从ViewController分离View
之前的代码中,View的数据加载逻辑放在了总的ViewController中,增加了耦合性,应该对控制器ViewController隐藏数据加载到View的细节。
封装View的创建逻辑
封装View的数据加载逻辑到自定义的UIView中
B.思路
使用xib封装自定义view的步骤:
1.新建一个继承UIView的自定义view,这里的名字是“AppView”,用来封装独立控件组
每个AppView封装了如下图的控件组
2.新建一个xib文件来描述控件结构,就是上图的控件组
3.在Controller中使用AppView作为每个独立控件组的类型单位
4.将控件和View “AppView” 进行连线
5.View “AppView” 提供一个模型属性
6.重写模型属性的setter,解析模型数据
7.设置模型数据到控件中
8.自定义View “AppView”的构造方法,屏蔽读取xib文件的细节
其实这就是一种简单的MVC模式
Model: App.h, App.m
View: AppView.h, AppView.m
Controller: ViewController.h, ViewController.m
Controller连接了View和Model,取得数据后加载到Model,然后传给View进行解析并显示
C.实现
1.新建UIView类”AppView",继承自UIView
new file ==> iOS ==> Source ==> Cocoa Touch Class
创建声明文件”AppView.h”和“AppView.m”
a.
b.
c.
2.设置xib的class (默认是UIView) 为新建的”AppView"
3.在新建的UIView中编写View的数据加载逻辑
(1)在”AppView.h”中创建Model成员
// 在Controller和View之间传输的Model数据 @property(nonatomic, strong) App *appData;
(2)连接控件和”AppView",创建私有控件成员
(3)在”AppView.m”中解析加载数据
- (void)setAppData:(App *)appData { _appData = appData; // 1.设置图片 self.iconView.image = [UIImage imageNamed:appData.icon]; // 2.设置名字 self.nameLabel.text = appData.name; }
(4)自定义构造方法
AppView.h:
// 自定义将Model数据加载到View的构造方法 - (instancetype) initWithApp:(App *) appData; // 自定义构造的类方法 + (instancetype) appViewWithApp:(App *) appData; // 返回一个不带Model数据的类构造方法 + (instancetype) appView; AppView.m: // 自定义将Model数据加载到View的构造方法 - (instancetype) initWithApp:(App *) appData { // 1.从NIB取得控件 UINib *nib = [UINib nibWithNibName:@"app" bundle:[NSBundle mainBundle]]; NSArray *viewArray = [nib instantiateWithOwner:nil options:nil]; AppView *appView = [viewArray lastObject]; // 2.加载Model appView.appData = appData; return appView; } // 自定义构造的类方法 + (instancetype) appViewWithApp:(App *) appData { return [[self alloc] initWithApp:appData]; } // 返回一个不带Model数据的类构造方法 + (instancetype) appView { return [self appViewWithApp:nil]; }
(5)在Controller中创建”AppView”并加载数据
// 1.创建View AppView *appView = [AppView appViewWithApp:appData]; // 2.定义每个app的位置、尺寸 CGFloat appX = marginX + column * (marginX + APP_WIDTH); CGFloat appY = marginY + row * (marginY + APP_HEIGHT); appView.frame = CGRectMake(appX, appY, APP_WIDTH, APP_HEIGHT); // 3.加入此app信息到总view [self.view addSubview:appView];
主要代码
ViewController.m
#import "ViewController.h" #import "App.h" #import "AppView.h" #define ICON_KEY @"icon" #define NAME_KEY @"name" #define APP_WIDTH 85 #define APP_HEIGHT 90 #define MARGIN_HEAD 20 #define ICON_WIDTH 50 #define ICON_HEIGHT 50 #define NAME_WIDTH APP_WIDTH #define NAME_HEIGHT 20 #define DOWNLOAD_WIDTH (APP_WIDTH - 20) #define DOWNLOAD_HEIGHT 20 @interface ViewController () /** 存放应用信息 */ @property(nonatomic, strong) NSArray *apps; // 应用列表 @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. [self loadApps]; } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } #pragma mark 取得应用列表 - (NSArray *) apps { if (nil == _apps) { // 1.获得plist的全路径 NSString *path = [[NSBundle mainBundle] pathForResource:@"app.plist" ofType:nil]; // 2.加载数据 NSArray *dictArray = [NSArray arrayWithContentsOfFile:path]; // 3.将dictArray里面的所有字典转成模型,放到新数组中 NSMutableArray *appArray = [NSMutableArray array]; for (NSDictionary *dict in dictArray) { // 3.1创建模型对象 App *app = [App appWithDictionary:dict]; // 3.2 添加到app数组中 [appArray addObject:app]; } _apps = appArray; } return _apps; } #pragma mark 加载全部应用列表 - (void) loadApps { int appColumnCount = [self appColumnCount]; int appRowCount = [self appRowCount]; CGFloat marginX = (self.view.frame.size.width - APP_WIDTH * appColumnCount) / (appColumnCount + 1); CGFloat marginY = (self.view.frame.size.height - APP_HEIGHT * appRowCount) / (appRowCount + 1) + MARGIN_HEAD; int column = 0; int row = 0; for (int index=0; index<self.apps.count; index++) { App *appData = self.apps[index]; // 1.创建View AppView *appView = [AppView appViewWithApp:appData]; // 2.定义每个app的位置、尺寸 CGFloat appX = marginX + column * (marginX + APP_WIDTH); CGFloat appY = marginY + row * (marginY + APP_HEIGHT); appView.frame = CGRectMake(appX, appY, APP_WIDTH, APP_HEIGHT); // 3.加入此app信息到总view [self.view addSubview:appView]; column++; if (column == appColumnCount) { column = 0; row++; } } } #pragma mark 计算列数 - (int) appColumnCount { int count = 0; count = self.view.frame.size.width / APP_WIDTH; if ((int)self.view.frame.size.width % (int)APP_WIDTH == 0) { count--; } return count; } #pragma mark 计算行数 - (int) appRowCount { int count = 0; count = (self.view.frame.size.height - MARGIN_HEAD) / APP_HEIGHT; if ((int)(self.view.frame.size.height - MARGIN_HEAD) % (int)APP_HEIGHT == 0) { count--; } return count; } @end
AppView.m:
#import "AppView.h" #import "App.h" // 封装私有属性 @interface AppView() // 封装View中的控件,只允许自己访问 @property (weak, nonatomic) IBOutlet UIImageView *iconView; @property (weak, nonatomic) IBOutlet UILabel *nameLabel; @end @implementation AppView - (void)setAppData:(App *)appData { // 1.赋值Medel成员 _appData = appData; // 2.设置图片 self.iconView.image = [UIImage imageNamed:appData.icon]; // 3.设置名字 self.nameLabel.text = appData.name; } // 自定义将Model数据加载到View的构造方法 - (instancetype) initWithApp:(App *) appData { // 1.从NIB取得控件 UINib *nib = [UINib nibWithNibName:@"app" bundle:[NSBundle mainBundle]]; NSArray *viewArray = [nib instantiateWithOwner:nil options:nil]; AppView *appView = [viewArray lastObject]; // 2.加载Model appView.appData = appData; return appView; } // 自定义构造的类方法 + (instancetype) appViewWithApp:(App *) appData { return [[self alloc] initWithApp:appData]; } // 返回一个不带Model数据的类构造方法 + (instancetype) appView { return [self appViewWithApp:nil]; } @end
App.m
#import "App.h"
#define ICON_KEY @"icon"
#define NAME_KEY @"name"
@implementation App
- (instancetype) initWithDictionary:(NSDictionary *) dictionary {
if (self = [super init]) {
self.name = dictionary[NAME_KEY];
self.icon = dictionary[ICON_KEY];
}
return self;
}
+ (instancetype) appWithDictionary:(NSDictionary *) dictionary {
// 使用self代表类名代替真实类名,防止子类调用出错
return [[self alloc] initWithDictionary:dictionary];
}
@end
#import "App.h" #define ICON_KEY @"icon" #define NAME_KEY @"name" @implementation App - (instancetype) initWithDictionary:(NSDictionary *) dictionary { if (self = [super init]) { self.name = dictionary[NAME_KEY]; self.icon = dictionary[ICON_KEY]; } return self; } + (instancetype) appWithDictionary:(NSDictionary *) dictionary { // 使用self代表类名代替真实类名,防止子类调用出错 return [[self alloc] initWithDictionary:dictionary]; } @end
郑重声明:本站内容如果来自互联网及其他传播媒体,其版权均属原媒体及文章作者所有。转载目的在于传递更多信息及用于网络分享,并不代表本站赞同其观点和对其真实性负责,也不构成任何其他建议。