UI_05 设计模式、⼿势识别器

⼀、target/action设计模式

耦合

     耦合是衡量⼀个程序写的好坏的标准之⼀， 是衡量模块与模块之间关联程度的指标。 “⾼内聚，低耦合”是⾯向对象编程的核⼼思想。

使⽤target…action实现解耦

touchView.h:

@interface TouchView : UIView

@property (nonatomic, retain) id target;
@property (nonatomic, assign) SEL action;

- (instancetype)initWithTarget:(id)target action:(SEL)action;

@end

touchView.m

- (instancetype)initWithTarget:(id)target action:(SEL)action
{
    self = [super init];
    if (self) {
        self.target = target;
        self.action = action;
    }
    return self;
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    NSLog(@"clicked");
    [self.target performSelector:self.action withObject:self];

}

RootViewController.h

#import "RootViewController.h"

#import "TouchView.h"
#import "UIColor+RandomColor.h"

@interface RootViewController ()
@property (nonatomic, retain) TouchView *aTouchView;
@end

@implementation RootViewController

- (void)dealloc
{
    [_aTouchView release];
    [super dealloc];
}

- (void)viewDidLoad {
    [super viewDidLoad];
   

    self.aTouchView = [[TouchView alloc] initWithTarget:self action:@selector(changeColor:)];

    //changeColor:方法的参数为TouchView.m中performSelector: withObject:方法的obj        

    //[_target performSelector:sel withObject:obj];

    //一个Target-Action在一个时间只能作一个事件

    self.aTouchView.frame = CGRectMake(100, 100, 200, 200);
    self.aTouchView.backgroundColor = [UIColor redColor];

    [self.view addSubview:_aTouchView];
    [self.aTouchView release];

    self.view.backgroundColor = [UIColor blueColor];
}

- (void)changeColor:(TouchView *)view
{
    view.backgroundColor = [UIColor randomColor];

}

@end

---

⼆、代理设计模式

delegate也是⽤来解耦的，它再也不简简单单让⺫标去执⾏⼀个动 做了，⽽是delegate去处理⼀些列事件、就像UITextFieldDelegate⼀ 样，能监测将要开始编辑，已经开始编辑、return按钮点击等等。

经过使用代理设计模式，实现开始点击自定义视图touchView时变换颜色，结束点击时变换位置

TouchViewDelegate.h

#import <Foundation/Foundation.h>
@class TouchView;
//#import "TouchView.h"
@protocol TouchViewDelegate <NSObject>

@optional

- (void)touchViewTouchBegan:(TouchView *)touchView;     //作饭

- (void)touchViewTouchMoved:(TouchView *)touchView;

- (void)touchViewTouchEnd:(TouchView *)touchView;

- (void)touchViewTouchCancel:(TouchView *)touchView;

@end

touchView.h

@interface TouchView : UIView

@property (nonatomic, assign) id<TouchViewDelegate> delegate;  //保姆

@end

toucheView.m

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event  // 饿了

{

#pragma mark -- Delegate --

    if ([self.delegate respondsToSelector:@selector(touchViewTouchBegan:)]) {
        [self.delegate touchViewTouchBegan:self];
    }
    if ([self.delegate respondsToSelector:@selector(touchViewTouchEnd:)]) {
        [self.delegate touchViewTouchEnd:self];

    }

}

RootViewController.m

#import "RootViewController.h"
#import "TouchView.h"

@interface RootViewController ()
{
    TouchView *_touchView1;
    TouchView *_touchView2;
}
@end

@implementation RootViewController

- (void)viewDidLoad {
    [super viewDidLoad];
   
    _touchView1 = [[TouchView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
    _touchView1.backgroundColor = [UIColor blueColor];

    

#pragma mark -- Delegate --
    //设置代理

    _touchView1.delegate = self;

    [self.view addSubview:_touchView1];
    [_touchView1 release];

}

#pragma mark -- Delegate --

- (void)touchViewTouchBegan:(TouchView *)touchView     //作饭

{

    touchView.backgroundColor = [UIColor colorWithRed:arc4random() %256 / 255.0 green:arc4random() %256 / 255.0 blue:arc4random() %256 / 255.0 alpha:arc4random() %100 / 100.0];;

}

- (void)touchViewTouchEnd:(TouchView *)touchView
{
    touchView.center = CGPointMake(50, 50);

}

@end

利用家庭－保姆来理解：

     TouchView:     家庭类

  ContainerViewController:保姆类

  TouchViewDelegate:      协议

  

---

3、UIImageView

     UIImageView是iOS中⽤于显⽰图⽚的类，iOS中⼏乎全部看到的 图⽚，都是由这个类来显⽰的。

下面用UIImageView分别演示如何添加静态和动态图片

一、UIImageView常⽤属性

    image //设置图⽚

    animationImages //设置⼀组动态图⽚

    animationDuration //设置播放⼀次⼀组动态图⽚的时间

    animationRepeatCount //设置重复次数

    startAnimating //开始动画

    stopAnimating //结束动画

二、UIImageView帧动画相关属性和方法

    @property(nonatomic,copy) NSArray *animationImages;
    须要播放的序列帧图片数组（里面都是UIImage对象，会按顺序显示里面的图片）
    @property(nonatomic) NSTimeInterval animationDuration;
    帧动画的持续时间
    @property(nonatomic) NSInteger animationRepeatCount;
    帧动画的执行次数（默认是无限循环）
    - (void)startAnimating;
    开始执行帧动画
    - (void)stopAnimating;
    中止执行帧动画
    - (BOOL)isAnimating;

    是否正在执行帧动画

三、UIImage的2种加载方式

方式一：有缓存（图片所占用的内存会一直停留在程序中）

+ (UIImage*)imageNamed:(NSString*)name;

方式二：无缓存（图片所占用的内存会在一些特定操做后被清除）

+ (UIImage *)imageWithContentsOfFile:(NSString *)path
- (id)initWithContentsOfFile:(NSString *)path;

+ (UIImage*)imageWithContentsOfFile:(NSString *)path

- (id)initWithContentsOfFile:(NSString*)path;

RootViewController.m

#import "RootViewController.h"
#import "UIColor+RandomColor.h"

@interface RootViewController ()
@property (nonatomic,retain) UIImageView *imgView;

@end

@implementation RootViewController

- (void)dealloc
{
    [_imgView release];

    [super dealloc];

}

- (void)viewDidLoad {
    [super viewDidLoad];
   

#pragma mark -- UImageView --

    self.imgView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"1.png"]];   PNG格式的图片能够省略扩展名

    // 若是设置_imgView.frame,则图片大小为frame大小，发生形变。若不设置，则frame的大小为图片的大小。
//    _imgView.frame = CGRectMake(0, 0, 371, 600);
    NSLog(@"%.f %.f", _imgView.frame.size.width, _imgView.frame.size.height);
    [self.view addSubview:_imgView];

    [_imgView release];

#pragma mark -- 使用UIImageView播放动画图片gif --
    UIImageView * animationImage = [[UIImageView alloc] init];
    animationImage.frame = CGRectMake(100, 350, 150, 150);
   
    NSMutableArray * imagesArr = [NSMutableArray array];
    for (int i = 1; i<4; i++) {
        UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:@"tu%d.tiff", i]];
        [imagesArr addObject:image];
    }
   
    animationImage.animationImages = imagesArr;
    animationImage.animationDuration = 0.1;
    [animationImage startAnimating];
//    [animationImage stopAnimating];
   
    [self.view addSubview:animationImage];

    [animationImage release];

}

...

@end

---

4、⼿势识别器

     ⼿势识别器是对触摸事件作了封装，咱们⽆需⾃⼰去判断某个⼿势 是否触发，⼿势识别器本⾝起到了识别做⽤，咱们把重⼼放在识别之 后要作什么操做上⾯。

     ⼿势识别器有7个⼦类,⼀旦指定的⼿势被识别，咱们能够执⾏咱们⾃⼰定义好的操做。

• 轻拍⼿势:UITapGestureRecognizer

• 平移⼿势:UIPanGestureRecognizer

• 轻扫⼿势: UISwipeGestureRecognizer

• 捏合⼿势:UIPinchGestureRecognizer

• 旋转⼿势:UIRotationGestureRecognizer

• ⻓按⼿势:UILongPressGestureRecognizer

• 屏幕边界平移⼿势: UIScreenEdgePanGestureRecognizer(iOS7+)

RootViewController.m 

@interface RootViewController ()
@property (nonatomic,retain) UIImageView *imgView;
@property (nonatomic, retain) UIView *tapView;
@end

@implementation RootViewController

- (void)dealloc
{
    [_imgView release];
    [_tapView release];
    [super dealloc];

}

- (void)viewDidLoad {

    [super viewDidLoad];   

#pragma mark -- UIGestureRecognizer --
    UIView * tapView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
    tapView.backgroundColor = [UIColor grayColor];
    self.tapView = tapView;
    [self.view addSubview:tapView];
    [tapView release];
    //轻拍手势
    UITapGestureRecognizer * tapGR = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapOnce:)];
    //添加手势
    [self.tapView addGestureRecognizer:tapGR];
    [tapGR release];
   
    //长按手势
    UILongPressGestureRecognizer * longGR = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress:)];
    [self.tapView addGestureRecognizer:longGR];
    [longGR release];
   
    //平移手势
    UIPanGestureRecognizer * panGR = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(pan:)];
    [self.tapView addGestureRecognizer:panGR];
   
//    [animationImage addGestureRecognizer:panGR];
    [panGR release];
   
    //捏合手势
    UIPinchGestureRecognizer * pinchGR = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinch:)];
    [self.tapView addGestureRecognizer:pinchGR];
    [pinchGR release];
   
    //旋转
    UIView * aView = [[UIView alloc] initWithFrame:CGRectMake(0, 100, 100, 100)];
    aView.backgroundColor = [UIColor brownColor];
    [self.view addSubview:aView];
    [aView release];
    UIRotationGestureRecognizer * rotationGR = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotation:)];
    [aView addGestureRecognizer:rotationGR];
    [rotationGR release];

   

    //轻扫 

//    UISwipeGestureRecognizer
   
    //屏幕边界平移手势

//    UIScreenEdgePanGestureRecognizer

}

- (void)tapOnce:(UITapGestureRecognizer *)GR
{
//    self.tapView.hidden = YES;
//    self.tapView.backgroundColor = [UIColor randomColor];
    NSLog(@"");
}

- (void)longPress:(UILongPressGestureRecognizer *)GR
{
    GR.view.backgroundColor = [UIColor randomColor];
}

- (void)pan:(UIPanGestureRecognizer *)GR
{
   
    CGPoint translation = [GR translationInView:GR.view];
    NSLog(@"%@", NSStringFromCGPoint(translation));
    CGPoint center = GR.view.center;
    center.x += translation.x;
    center.y += translation.y;
    GR.view.center = center;
   
    [GR setTranslation:CGPointMake(0, 0) inView:GR.view];

}

- (void)pinch:(UIPinchGestureRecognizer *)GR
{
   
    GR.view.transform = CGAffineTransformScale(GR.view.transform, GR.scale, GR.scale);
    GR.scale = 1;
   
}

- (void)rotation:(UIRotationGestureRecognizer *)GR
{
    //第二个参数是弧度
    //180度 3.1415926 M_PI
    GR.view.transform = CGAffineTransformRotate(GR.view.transform, GR.rotation);
    GR.rotation = 0;

}

...

@end

    利用transform属性能够修改控件的位移（位置）、缩放、旋转
   
    建立一个transform属性

    CGAffineTransform CGAffineTransformMakeTranslation(CGFloat tx,  CGFloat ty) ;

    CGAffineTransform CGAffineTransformMakeScale(CGFloat sx, CGFloat sy);

    CGAffineTransform CGAffineTransformMakeRotation(CGFloat angle)

    (注意：angle是弧度制，并非角度制)
   
    在某个transform的基础上进行叠加

    CGAffineTransform CGAffineTransformTranslate(CGAffineTransform t, CGFloat tx, CGFloat ty);

    CGAffineTransform CGAffineTransformScale(CGAffineTransform t, CGFloat sx, CGFloat sy);
    CGAffineTransform CGAffineTransformRotate(CGAffineTransform t, CGFloat angle);
   
    清空以前设置的transform属性

    view.transform = CGAffineTransformIdentity;