1. 基本概念
页面传值有多种方式，今天学的是通过属性传值和代理传值。属性传值就是通过一个按钮或者其他的控件加上触发函数传值。
2. 属性传值
删去ViewController文件，在新建三个视图控制器文件。在AppDelegare中创建window和视图一和视图三，还有一个工具栏一个导航栏：
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #d12f1b}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #4f8187}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #bb2ca2}p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p6 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #008400}p.p7 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3d1d81}p.p8 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #703daa}span.s1 {font-variant-ligatures: no-common-ligatures; color: #78492a}span.s2 {font-variant-ligatures: no-common-ligatures}span.s3 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s4 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s5 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s6 {font-variant-ligatures: no-common-ligatures; color: #4f8187}span.s7 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s8 {font-variant-ligatures: no-common-ligatures; color: #d12f1b}span.s9 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures; color: #d12f1b}
#import "AppDelegate.h"
#import "VCFirst.h"
#import "VCThird.h"
@interface AppDelegate ()
@end
@implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Override point for customization after application launch.
self.window=[[UIWindow alloc]initWithFrame:[UIScreen mainScreen].bounds];
[self.window makeKeyAndVisible];
VCFirst* vcFirst=[[VCFirst alloc]init];
vcFirst.title=@"视图一";
vcFirst.view.backgroundColor=[UIColor whiteColor];
UINavigationController* nav=[[UINavigationController alloc]initWithRootViewController:vcFirst];
VCThird* vcThird=[[VCThird alloc]init];
vcThird.title=@"视图三";
vcThird.view.backgroundColor=[UIColor greenColor];
UINavigationController* nav2=[[UINavigationController alloc]initWithRootViewController:vcThird];
NSArray* array=[NSArray arrayWithObjects:nav,nav2,nil];
UITabBarController* tabVC=[[UITabBarController alloc]init];
tabVC.viewControllers=array;
self.window.rootViewController=tabVC;
return YES;
}
然后在视图一中创建视图二：
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #bb2ca2}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3d1d81}p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #008400}p.p6 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #703daa}p.p7 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Heiti SC Light'; color: #008400}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s3 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s4 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s5 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s6 {font-variant-ligatures: no-common-ligatures; color: #4f8187}span.s7 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s8 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures; color: #000000}span.s9 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures}span.s10 {font-variant-ligatures: no-common-ligatures; color: #d12f1b}span.s11 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures; color: #d12f1b}
@implementation VCFirst
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
}
-(void)changeColor:(UIColor *)color
{
self.view.backgroundColor=color;
}
//创建视图控制器二
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
VCSecond* vcSecond=[[VCSecond alloc]init];
//将当前的控制器作为代理对象赋值
//delegate相当于是vcSecond的属性
// vcSecond.delegate=self;
vcSecond.title=@"视图二";
vcSecond.view.backgroundColor=[UIColor purpleColor];
[self.navigationController pushViewController:vcSecond animated:YES];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
视图结构为：
----视图一 ---->视图二
----视图三
这时在VCFirst中可以直接改变视图二的颜色。
3. 代理传值
这部分主要解决怎么通过改变视图二中的代码，可以控制改变视图一的颜色。
在视图二中添加一个按钮：
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3d1d81}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #008400}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #703daa}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s3 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s4 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s5 {font-variant-ligatures: no-common-ligatures; color: #d12f1b}span.s6 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures; color: #d12f1b}
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
UIBarButtonItem* btnChange=[[UIBarButtonItem alloc]initWithTitle:@"改变颜色" style:UIBarButtonItemStyleDone target:self action:@selector(pressChange)];
self.navigationItem.rightBarButtonItem=btnChange;
}
然后在视图二的头文件里定义协议：
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #d12f1b}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Heiti SC Light'; color: #008400}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #bb2ca2}p.p6 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #703daa}span.s1 {font-variant-ligatures: no-common-ligatures; color: #78492a}span.s2 {font-variant-ligatures: no-common-ligatures}span.s3 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s4 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s5 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s6 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s7 {font-variant-ligatures: no-common-ligatures; color: #4f8187}
#import
//定义一个代理协议
//是视图控制器二的协议
@protocol VCSecondDelegate
//定义协议函数
-(void)changeColor:(UIColor*)color;
@end
@interface VCSecond : UIViewController
@property(assign,nonatomic)NSInteger tag;
//定义一个代理对象
//代理对象会执行协议函数
//通过代理对象实现协议函数，达到代理对象改变本身属性的目的
//代理对象一定要实现代理协议
@property(assign,nonatomic)id delegate;
@end
在视图一创建视图二的过程中将视图一赋值为代理对象：
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #4f8187}span.s3 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}
vcSecond.delegate=self;
完整代码即
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Heiti SC Light'; color: #008400}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #008400}p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #703daa}p.p6 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3d1d81}span.s1 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures}span.s3 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s4 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s5 {font-variant-ligatures: no-common-ligatures; color: #4f8187}span.s6 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s7 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures; color: #000000}span.s8 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s9 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures}span.s10 {font-variant-ligatures: no-common-ligatures; color: #d12f1b}span.s11 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures; color: #d12f1b}
//创建视图控制器二
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
VCSecond* vcSecond=[[VCSecond alloc]init];
//将当前的控制器作为代理对象赋值
//delegate相当于是vcSecond的属性
vcSecond.delegate=self;
vcSecond.title=@"视图二";
vcSecond.view.backgroundColor=[UIColor purpleColor];
[self.navigationController pushViewController:vcSecond animated:YES];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
最后去视图二中实现按钮触发函数：
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Heiti SC Light'; color: #008400}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}span.s1 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures}span.s3 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s4 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures; color: #000000}span.s5 {font-variant-ligatures: no-common-ligatures; color: #4f8187}span.s6 {font-variant-ligatures: no-common-ligatures; color: #31595d}span.s7 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s8 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}
//点击按钮时触发事件
-(void)pressChange
{
//代理对象调用事件函数
[_delegate changeColor:[UIColor redColor]];
}
最终效果：
屏幕快照 2016-12-08 上午11.04.57.png
屏幕快照 2016-12-08 上午11.05.06.png
屏幕快照 2016-12-08 上午11.05.13.png