UI - Target-Action设计模式

#TouchView.h

#import <UIKit/UIKit.h>
@interface TouchView : UIView
#warning 1.给外界提供目标和动作属性,让外界可以设置
@property(nonatomic,retain)id target; // 目标
@property(nonatomic,assign)SEL action; // 动作
@end

#TouchView.m

#import "TouchView.h"
@implementation TouchView
#warning 2.重写dealloc方法释放对应的实例变量
- (void)dealloc
{
[_target release];
[super dealloc];
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
// 1.我们现在面临了什么问题
// 2.通过到目前为止学过的知识点 怎样可以实现题目的需求
//    [self ChangeColor];
// 更改为目标去执行[目标 方法];
#warning 4.在某个时间点让目标取执行对应的方法
[_target performSelector:_action withObject:self];
// 让target去执行action这个方法并且把self参数传出去 (self:当前点击的touchView)
}

#RootViewController.m

#import "RootViewController.h"
#import "TouchView.h"
@interface RootViewController ()

@end

@implementation RootViewController

- (void)viewDidLoad {
[super viewDidLoad];
// target - action设计模式
/**
target - action 是模仿系统的Button 即将事件的处理交给外界 不在自己的内部写死
target-action设计模式主要涉及到两方面的内容
target:目标
action:动作
target-action可以让不同的实例对象在相同的时间点执行不用的方法 从而达到不同的效果
target-action设计模式存在的意义即将时间分离 View只负责显示 具体的事情处理交给Controller 是MVC中View层和Controller层通信的一种方式
*/

// 创建三个实例对象
TouchView *changeColorView = [[TouchView alloc]initWithFrame:CGRectMake(50, 50, 100, 100)];
changeColorView.backgroundColor = [UIColor yellowColor];
#warning 3.在外界设置target action
changeColorView.target = self;
changeColorView.action = @selector(ChangeColor:);
[self.view addSubview:changeColorView];

TouchView *changePostionView = [[TouchView alloc]initWithFrame:CGRectMake(50, 200, 100, 100)];
changePostionView.backgroundColor = [UIColor redColor];
changePostionView.target = self;
changePostionView.action = @selector(ChangePostion:);
[self.view addSubview:changePostionView];

TouchView *changeSizeView = [[TouchView alloc]initWithFrame:CGRectMake(50, 350, 100, 100)];
changeSizeView.backgroundColor = [UIColor purpleColor];
changeSizeView.target = self;
changeSizeView.action = @selector(ChangeBounds:);
[self.view addSubview:changeSizeView];

[changeColorView release];
[changePostionView release];
[changeSizeView release];
}
#warning 5.实现action方法
//- (void)ChangeColor:(TouchView *)view
//{
//    // 1.修改self.view的颜色为红色
////    self.view.backgroundColor = [UIColor redColor];
//    // 2.修改当前点击视图的颜色为随机色
//    view.backgroundColor = [UIColor colorWithRed:arc4random()%256/255.0 green:arc4random()%256/255.0 blue:arc4random()%256/255.0 alpha:1.0];
//}

#pragma mark - 改变背景颜色
- (void)ChangeColor:(TouchView *)view
{
view.backgroundColor = [UIColor colorWithRed:arc4random()%256/255.0 green:arc4random()%256/255.0 blue:arc4random()%256/255.0 alpha:1.0];
}
#pragma mark - 改变视图位置
- (void)ChangePostion:(TouchView *)view
{
CGFloat minX = 0;
CGFloat maxX = [[UIScreen mainScreen]bounds].size.width;
CGFloat x = arc4random()%(int)(maxX - minX + 1) + minX;
CGFloat minY = 0;
CGFloat maxY = [[UIScreen mainScreen]bounds].size.height;
CGFloat y = arc4random()%(int)(maxY - minY + 1) + minY;
view.center = CGPointMake(x, y);
}
#pragma mark - 改变
4000
视图大小
- (void)ChangeBounds:(TouchView *)view
{
CGFloat minWidth = 38;
CGFloat maxWidth = [[UIScreen mainScreen]bounds].size.width;
CGFloat width = arc4random()%(int)(maxWidth - minWidth + 1) + minWidth;
CGFloat minHeight = 38;
CGFloat maxHeight = [[UIScreen mainScreen]bounds].size.height;
CGFloat height = arc4random()%(int)(maxHeight - minHeight + 1) + minHeight;
view.bounds = CGRectMake(0, 0, width, height);
}