自定义视图 视图控制器(UIViewController)

CustomViewAndUIViewController

loadView方法内部对self.view进行创建

RootViewController继承于UIViewContrller的子类

自定义视图

    1.设计控件布局

    2.找到底板, 以底板的类为父类, 创建一个子类

    3.针对底板上的控件, 依次写属性

    4.重写父类(UIView)的初始化方法, 在初始化方法内部对底板上的控件进行创建

    5.创建一个自定义视图类的对象, 验证自定义视图(布局, 样式)

 

AppDelegate.m
 (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    

    RootViewController *rootVC = [[RootViewController alloc] init];
    self.window.rootViewController = rootVC;
    [rootVC release]; 
    
    return YES;
}

RootViewController.m

- (void)loadView {
//    self.view = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    self.view = [[LoginView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
      NSLog(@"加载视图");
}

视图已经加载完成
- (void)viewDidLoad {
    NSLog(@"视图已经加载完成");
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor cyanColor];
    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
    label.text = @"周一见!";
    label.tag = 100;
    [self.view addSubview:label];
    [label release];
    
    self.view.backgroundColor = [UIColor colorWithRed:0.952 green:1.000 blue:0.456 alpha:1.000];

    LoginView *loginView = [[LoginView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    loginView.backgroundColor = [UIColor colorWithRed:0.957 green:1.000 blue:0.420 alpha:1.000];
    [self.view addSubview:loginView];
    [loginView release];
    
}

当应用的内存快不够用时, 就会发出警告, 系统会让当前显示的视图控制器执行didReceiveMemoryWarning
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
    NSLog(@"收到内存警告");
    UILabel *label = (UILabel *)[self.view viewWithTag:100];
   从父视图移除某个子视图
    [label removeFromSuperview];   
}

#import "HomeViewController.h"
#define kSize 100
@interface HomeViewController () {
    UILabel *label2;
    UILabel *label3;
    UILabel *label4;
}

@end
@implementation HomeViewController
- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    self.view.backgroundColor = [UIColor colorWithRed:0.998 green:0.704 blue:1.000 alpha:1.000];
    UILabel *label1 = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, kSize, kSize)];
    label1.backgroundColor = [UIColor yellowColor];
    label1.text = @"1";
    label1.font = [UIFont systemFontOfSize:80];
    label1.textAlignment = NSTextAlignmentCenter;
    [self.view addSubview:label1];
    [label1 release];   
    label2 = [[UILabel alloc] initWithFrame:CGRectMake(375 - kSize, 0, kSize, kSize)];
    label2.backgroundColor = [UIColor yellowColor];
    label2.text = @"2";
    label2.font = [UIFont systemFontOfSize:80];
    label2.textAlignment = NSTextAlignmentCenter;
    [self.view addSubview:label2];
    [label2 release];
    label3 = [[UILabel alloc] initWithFrame:CGRectMake(0, 667 - kSize, kSize, kSize)];
    label3.backgroundColor = [UIColor yellowColor];
    label3.text = @"3";
    label3.font = [UIFont systemFontOfSize:80];
    label3.textAlignment = NSTextAlignmentCenter;
    [self.view addSubview:label3];
    [label3 release];

    label4 = [[UILabel alloc] initWithFrame:CGRectMake(375 - kSize, 667 - kSize, kSize, kSize)];
    label4.backgroundColor = [UIColor yellowColor];
    label4.backgroundColor = [UIColor yellowColor];
    label4.text = @"4";
    label4.font = [UIFont systemFontOfSize:80];
    label4.textAlignment = NSTextAlignmentCenter;
    [self.view addSubview:label4];
    [label4 release];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

UIViewController控制旋转的方法
是否支持旋转, 默认YES
- (BOOL)shouldAutorotate {
    return YES;
}

- (NSUInteger)supportedInterfaceOrientations {
        
        UIInterfaceOrientationMaskPortrait: 肖像模式
        UIInterfaceOrientationMaskLandscapeRight: 风景模式右
        UIInterfaceOrientationMaskPortraitUpsideDown: 肖像模式倒置
        UIInterfaceOrientationMaskLandscape: 风景模式(左, 右)
        UIInterfaceOrientationMaskAll: 四个方向
        UIInterfaceOrientationMaskAllButUpsideDown: 除了肖像模式倒置的所有方向
        
        iPhone项目 默认:  UIInterfaceOrientationMaskAllButUpsideDown
        iPad项目 默认: UIInterfaceOrientationMaskAll
    return UIInterfaceOrientationMaskAll;
}

视图将要旋转, 执行这个方法
- (void)viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator {
    size, 当前视图的大小
    NSLog(@"%@", NSStringFromCGSize(size));
    if (size.width > size.height) {
        NSLog(@"横屏");
        view的frame不允许单独修改, 必须整体修改
        //1
        label2.frame = CGRectMake(667 - kSize, 0, kSize, kSize);
        //2
        CGRect rect = label2.frame;
        rect.origin.x = size.width - kSize;
        label2.frame = rect;
    } else {
        NSLog(@"竖屏");
       label2.frame = CGRectMake(size.width - kSize, 0, kSize, kSize);
       
    }
    
    CGRect rect = label2.frame;
    rect.origin.x = size.width - kSize;
    label2.frame = rect;
    
    rect = label3.frame;
    rect.origin.y = size.height - kSize;
    label3.frame = rect;
    
    rect = label4.frame;
    rect.origin.y = size.height - kSize;
    rect.origin.x = size.width - kSize;
    label4.frame = rect;      
}

封装Label - TextField界面

LTView.h
#import <UIKit/UIKit.h>
@interface LTView : UIView
@property (nonatomic, retain) UILabel *label;
@property (nonatomic, retain) UITextField *textField;
@end

LTView.m
#import "LTView.h"
@implementation LTView
- (void)dealloc {
    [_label release];
    [_textField release];
    [super dealloc];
}
- (instancetype)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        //label
        _label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, frame.size.width / 3, frame.size.height)];
//        _label.backgroundColor = [UIColor colorWithRed:0.426 green:1.000 blue:0.956 alpha:1.000];
        _label.textAlignment = NSTextAlignmentCenter;
        [self addSubview:_label];
        [_label release];        
        //textField
        _textField = [[UITextField alloc] initWithFrame:CGRectMake(_label.frame.size.width, 0, frame.size.width - _label.frame.size.width, frame.size.height)];//frame.size.width / 3 * 2
//        _textField.backgroundColor = [UIColor whiteColor];
        [_textField setBorderStyle:(UITextBorderStyleRoundedRect)];
        [self addSubview:_textField];
        [_textField release];     
    }
    return self;
}
@end

封装Login界面

LoginView.h
#import <UIKit/UIKit.h>
@class LTView;
@interface LoginView : UIView
@property (nonatomic, retain) LTView *userNameView, *passwordView;
@property (nonatomic, retain) UIButton *button;
@end

LoginView.m
#import "LoginView.h"
#import "LTView.h"
@implementation LoginView
- (void)dealloc {
    [_userNameView release];
    [_passwordView release];
    [_button release];
    [super dealloc];
}

- (instancetype)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        //用户名
        self.userNameView = [[LTView alloc] initWithFrame:CGRectMake(50, 100, 275, 40)];
        _userNameView.label.text = @"用 户 名";
        _userNameView.textField.placeholder = @" 请输入用户名";
        [self addSubview:_userNameView];
        [_userNameView release];
        //密码
        self.passwordView = [[LTView alloc] initWithFrame:CGRectMake(50, 160, 275, 40)];
        _passwordView.label.text = @"密      码";
        _passwordView.textField.placeholder = @" 请输入密码";
        _passwordView.textField.secureTextEntry = YES;
        [self addSubview:_passwordView];
        [_passwordView release];
        //登录按钮
        self.button = [UIButton buttonWithType:UIButtonTypeSystem];
        _button.frame = CGRectMake(100, 220, 375 - 200, 40);
//        _button.backgroundColor = [UIColor greenColor];
//        _button.showsTouchWhenHighlighted = YES;
        [_button setTitle:@"登录" forState:UIControlStateNormal];
        _button.titleLabel.font = [UIFont systemFontOfSize:20];
        [self addSubview:_button];
    }
    return self;
}
@end

 MVC: 是一种设计框架

    M: model, 数据模型, 用于定义数据结构, 存储数据

    V: view, 视图, 用于展示内容

    C: controller, 控制器, 作为model和view的协调者

    1.MVC把,面向对象程序中出现的对象进行分类, 规定各自的作用

    2.model和view之间不能通信

    3.controller可以访问model和view, model和view不能访问controller

    4.view可以间接访问controller, 主要的通信手段

     a.target-action(目标动作机制)

     b.delegate(代理模式)

     c.dataSource(也是代理模式, 只不过换了一个名字, 主要用于数据的传递)

    5.moodel可以间接访问controller, 主要的通信手段

     a.KVO(键值观察)

     b.notification(通知)

    UIViewController, 视图控制器, 属于控制类, view和model的协调者, 是MVC框架的核心, 继承于UIResponder, 管理iOS应用中的view

    把appDelegate中的视图创建的的代码, 转移到UIViewController中

    RootViewController *rootVC = [[RootViewController alloc] init];

    指定window的根视图控制器

    self.window.rootViewController = rootVC;

    [rootVC release];

    注: 视图控制器会自带一个UIView, 当指定window的根视图控制器后, 会出现window的上方, 并且和window的大小相同