首页 > 代码库 > iOS 使用UIView的一种有效方法
iOS 使用UIView的一种有效方法
在一个典型的MVC结构 中,Model部分负责保存目标数据,View部分主要负责实现数据的界面以及将数据显示出来,二者在Controller的操作下协同工作。在iOS应用中,View的实现主要由UIView及其派生类实现,主要由UILabel、UIImageView等等类来显示不同的信息。
这里展示一个demo来说明个人对UIView同数据交互的一种观点,个人意见仅供参考,欢迎讨论。
1、首先建立一个UIView的子类用于定制我们的视图对象
头文件:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 | #import <uikit uikit.h=""> @interface UserInfoView : UIView //@property (nonatomic,copy) NSString *imgString; //@property (nonatomic,copy) NSString *nameString; //@property (nonatomic,copy) NSString *addrString; //@property (nonatomic,copy) NSString *infoString; //@property (nonatomic,copy) NSString *countString; //@property (nonatomic,copy) NSString *attString; //@property (nonatomic,copy) NSString *fansString; @property (nonatomic,retain) NSDictionary *param; - (void)loadData; @end</uikit> |
m文件:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 | #import "UserInfoView.h" #import "RectButton.h" @interface UserInfoView() //UI控件 @property (nonatomic,retain) UIImageView *userImage; @property (nonatomic,retain) UILabel *nameLabel; @property (nonatomic,retain) UILabel *addressLabel; @property (nonatomic,retain) UILabel *infoLabel; @property (nonatomic,retain) UILabel *countLabel; @property (nonatomic,retain) RectButton *attButton; @property (nonatomic,retain) RectButton *fansButton; @property (nonatomic,retain) UIButton *profileButton; @property (nonatomic,retain) UIButton *moreButton; //数据成员 //@property (nonatomic,copy) NSString *imgString; @property (nonatomic,copy) NSString *nameString; @property (nonatomic,copy) NSString *addrString; @property (nonatomic,copy) NSString *infoString; @property (nonatomic,copy) NSString *countString; //@property (nonatomic,copy) NSString *attString; //@property (nonatomic,copy) NSString *fansString; @end @implementation UserInfoView - (id)init { CGRect frameRect = CGRectMake(0, 0, 320, 200); self = [self initWithFrame:frameRect]; if (self) { NSLog(@ "Init called" ); } return self; } - (id)initWithFrame:(CGRect)frame { self = [ super initWithFrame:frame]; if (self) { self.backgroundColor = [UIColor lightGrayColor]; _userImage = [[UIImageView alloc] initWithFrame:CGRectZero]; [self addSubview:_userImage]; _nameLabel = [[UILabel alloc] initWithFrame:CGRectZero]; [self addSubview:_nameLabel]; _addressLabel = [[UILabel alloc] initWithFrame:CGRectZero]; [self addSubview:_addressLabel]; _infoLabel = [[UILabel alloc] initWithFrame:CGRectZero]; [self addSubview:_infoLabel]; _attButton = [[RectButton alloc] initWithFrame:CGRectZero]; [self addSubview:_attButton]; _fansButton = [[RectButton alloc] initWithFrame:CGRectZero]; [self addSubview:_fansButton]; _profileButton = [[UIButton alloc] initWithFrame:CGRectZero]; [self addSubview:_profileButton]; _moreButton = [[UIButton alloc] initWithFrame:CGRectZero]; [self addSubview:_moreButton]; _countLabel = [[UILabel alloc] initWithFrame:CGRectZero]; [self addSubview:_countLabel]; } return self; } - (void)setParam:(NSDictionary *)param { _param = param; _nameString = [_param objectForKey:@ "Name" ]; _addrString = [_param objectForKey:@ "Address" ]; _infoString = [_param objectForKey:@ "Infomation" ]; _countString = [_param objectForKey:@ "Count" ]; [self loadData]; } - (void)layoutSubviews { _userImage.frame = CGRectMake(20, 20, 80, 80); _userImage.backgroundColor = [UIColor yellowColor]; _nameLabel.frame = CGRectMake(120, 20, 180, 20); _nameLabel.backgroundColor = [UIColor yellowColor]; _addressLabel.frame = CGRectMake(120, 50, 180, 20); _addressLabel.backgroundColor = [UIColor yellowColor]; _infoLabel.frame = CGRectMake(120, 80, 180, 20); _infoLabel.backgroundColor = [UIColor yellowColor]; _attButton.frame = CGRectMake(20, 110, 60, 60); _attButton.backgroundColor = [UIColor greenColor]; _fansButton.frame = CGRectMake(93, 110, 60, 60); _fansButton.backgroundColor = [UIColor greenColor]; _profileButton.frame = CGRectMake(167, 110, 60, 60); _profileButton.backgroundColor = [UIColor greenColor]; _moreButton.frame = CGRectMake(240, 110, 60, 60); _moreButton.backgroundColor = [UIColor greenColor]; _countLabel.frame = CGRectMake(20, 180, 280, 15); _countLabel.backgroundColor = [UIColor whiteColor]; [self loadData]; } - (void)loadData { if (self.nameString.length != 0) { _nameLabel.text = self.nameString; } if (self.addrString.length != 0) { _addressLabel.text = self.addrString; } if (self.infoString.length != 0) { _infoLabel.text = self.infoString; } if (self.countString.length != 0) { _countLabel.text = self.countString; } } @end |
在这个UserInfoView新建的时候,在initWithFrame中建立各个子视图,但是只是单纯新建一个对象而已,其frame设置为0。另 外,还重写了init函数,在函数中设置了指定的View大小,这样在Controller新建视图的时候不需要指定参数直接按照指定值进行操作。
UserInfoView中各个子视图的设置,在layoutSubView中完成,包括设置子视图的frame和背景颜色。layoutSubView函数可能经常被调用到,主要由以下几种情况:
· 当addSubView被调用时,被添加视图以及其子视图的layoutSubView会被调用;
· 当视图的frame发生改变时,会调用该视图的layoutSubView;
· 当滚动UIScrollView的时候会调用该视图及其父视图的layoutSubView;
· 旋转设备的时候;
· 向该视图发送setNeedLayout消息的时候。
2. 由Controller向View中发送数据
ViewController类的实现如下:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 | #import "ViewController.h" #import "UserInfoView.h" @interface ViewController () @property (nonatomic,retain) UIButton *People1; @property (nonatomic,retain) UIButton *People2; @property (nonatomic,retain) UserInfoView *userView; @end @implementation ViewController - (void)viewDidLoad { [ super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. _userView = [[UserInfoView alloc] init]; [self.view addSubview:_userView]; _People1 = [UIButton buttonWithType:UIButtonTypeSystem]; _People1.frame = CGRectMake(20, 240, 120, 40); [_People1 setTitle:@ "张三" forState:UIControlStateNormal]; _People1.backgroundColor = [UIColor lightGrayColor]; [_People1 addTarget:self action:@selector(setPeople1Data) forControlEvents:UIControlEventTouchUpInside]; [self.view addSubview:_People1]; _People2 = [UIButton buttonWithType:UIButtonTypeSystem]; _People2.frame = CGRectMake(180, 240, 120, 40); [_People2 setTitle:@ "李四" forState:UIControlStateNormal]; _People2.backgroundColor = [UIColor lightGrayColor]; [_People2 addTarget:self action:@selector(setPeople2Data) forControlEvents:UIControlEventTouchUpInside]; [self.view addSubview:_People2]; /* view.nameString = @"张三"; view.addrString = @"北京"; view.infoString = @"学生"; view.countString = @"12345"; view.nameString = @"李四"; view.addrString = @"上海"; view.infoString = @"工程师"; view.countString = @"54321";*/ } - (void)setPeople1Data { NSLog(@ "setPeople1Data called." ); NSDictionary *param = @{@ "Name" : @ "张三" , @ "Address" : @ "北京" , @ "Infomation" : @ "学生" , @ "Count" : @ "12345" }; _userView.param = param; } - (void)setPeople2Data { NSLog(@ "setPeople2Data called." ); NSDictionary *param = @{@ "Name" : @ "李四" , @ "Address" : @ "上海" , @ "Infomation" : @ "工程师" , @ "Count" : @ "54321" }; _userView.param = param; } - (void)didReceiveMemoryWarning { [ super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } @end |
ViewController的默认视图上,分别实现了两个按钮并分别设置了响应函数。我们的目的是通过选择不同的按钮来改变UserInfoView中 显示的数据。从两个响应函数setPeople1Data和setPeople2Data的实现可知,UserInfoView所需要的信息都被封装在了一个字典型变量param中,对view的修改仅仅做了一个操作,即将该字典变量赋给了UserInfoView实例的一个property,通过这种改变一下目标view属性的方式即可完成对显示信息的更改。这样,Controller并不关心UserInfoView实例是如何解析字典参数的,也不需要对该实例进行其他操作,当需要更新数据的时候只需要一次赋值就可以了。如此可以最大程度地解除Controller和View的耦合性,提高代码的逻辑简洁度和可复用性。
再回到 UserInfoView类中的实现方法。如何实现在字典类property改变的同时对自己的子视图进行重写数据操作呢?方法很简单。首先将重写子视图数据的代码分离到loadData函数中,然后重写NSDictionary *param这个property的set方法(即setParam),然后在该set方法和layoutSubView方法中调用loadData方法就可以了。
iOS 使用UIView的一种有效方法