属性传值 Block传值
2016-02-23 15:26 傅彦 阅读(134) 评论(0) 编辑 收藏 举报属性传值 就是将A页面的数据传到B页面上，下面就是将FirstViewController的TextField的内容传递到SecondViewController页面的导航栏标题和控制台输出上
#import
@interface FirstViewController :UIViewController
{
UITextField *tf;
}
@end
#import "FirstViewController.h"
#import "SecondViewController.h"//要将数据传到哪一个页面(ViewController)就引用那个头文件
- (void)viewDidLoad
{
[superviewDidLoad];
//定义一个按钮
UIButton* button = [UIButtonbuttonWithType:UIButtonTypeRoundedRect];
button.frame=CGRectMake(100,100,100,100);
button.backgroundColor= [UIColorredColor];
[button addTarget:selfaction:@selector(doButton)forControlEvents:UIControlEventTouchUpInside];
[self.viewaddSubview:button];
tf = [[UITextFieldalloc]initWithFrame:CGRectMake(10,300,100,40)];
tf.tintColor = [UIColororangeColor];
tf.backgroundColor = [UIColorgrayColor];
tf.tag =1000;
[self.viewaddSubview:tf];
}
-(void)doButton{
tf = (UITextField *)[self.viewviewWithTag:1000];
//push入栈引用计数+1，且控制权归系统
SecondViewController * seV =[[SecondViewControlleralloc]init];//将其实例化，否则找不到相应的属性
//直接属性传值
seV.naviTitle =tf.text;
seV.str =@"传值成功";//属性(赋值)所要传的值要写在推出下一个窗口前面
[self.navigationControllerpushViewController:seVanimated:YES];
}
@end
#import
@interface SecondViewController :UIViewController
@property(nonatomic,strong)NSString * str;
@property (nonatomic,retain)NSString *naviTitle;
@end
#import "SecondViewController.h"
@interface SecondViewController ()
@end
@implementation SecondViewController
@synthesize naviTitle =_naviTitle;
- (void)viewDidLoad
{
[superviewDidLoad];
// Do any additional setup after loading the view.
self.view = [[UIViewalloc]initWithFrame:CGRectMake(0,0,320,480)];
self.title =self.naviTitle;//只是为了显示第一页面传过来的内容将其显示到导航标题上
}
-(void)viewWillAppear:(BOOL)animated{
NSLog(@"%@",self.str);
NSLog(@"11---%@",self.naviTitle);
}
@end
Block传值
#import
@interface FirstViewController :UIViewController
{
UITextField *tf;
}
@property (nonatomic,retain)UILabel *label;
@end
#import "FirstViewController.h"
#import "SecondViewController.h"
@implementation FirstViewController
- (void)viewDidLoad
{
[superviewDidLoad];
//定义一个按钮
UIButton* button = [UIButtonbuttonWithType:UIButtonTypeRoundedRect];
button.frame=CGRectMake(100,100,100,100);
button.backgroundColor= [UIColorredColor];
[button addTarget:selfaction:@selector(doButton)forControlEvents:UIControlEventTouchUpInside];
[self.viewaddSubview:button];
//定义一个显示控件
self.label = [[UILabelalloc]initWithFrame:CGRectMake(0,400, 100, 40)];
self.label.backgroundColor = [UIColorgreenColor];
self.label.text = nil;//为了显示第二个视图控制器传过来的字符串
[self.viewaddSubview:self.label];
}
-(void)doButton{
tf = (UITextField *)[self.viewviewWithTag:1000];
//push入栈引用计数+1，且控制权归系统
SecondViewController * seV =[[SecondViewControlleralloc]init];//相对应的将其实例化，否则找不到相应的属性
//回调方法将输入框中的数据传输过来
[seVreturnText:^(NSString *showText) {
self.label.text = showText;
}];
[self.navigationControllerpushViewController:seV animated:YES];
}
@end
#import
typedefvoid (^ReturnTextBlock)(NSString *showText);//重新定义了一个名字
@interface SecondViewController :UIViewController
@property (nonatomic,retain)UITextField *tf;
@property (nonatomic,copy) ReturnTextBlock returnTextBlock;//定义的一个Block属性
- (void)returnText:(ReturnTextBlock)block;
@end
#import "SecondViewController.h"
- (void)viewDidLoad
{
[superviewDidLoad];
//定义一个输入框 将文字传给第一个界面，并且显示在UILabel上
self.tf = [[UITextFieldalloc]initWithFrame:CGRectMake(10,300, 100, 40)];
self.tf.tintColor = [UIColororangeColor];
self.tf.backgroundColor = [UIColorgrayColor];
[self.viewaddSubview:self.tf];
}
//在第一个界面传进来一个Block语句块的函数
//把传进来的Block语句块保存到本类的实例变量returnTextBlock（.h中定义的属性）中，然后寻找一个时机调用
-(void)returnText:(ReturnTextBlock)block{
self.returnTextBlock = block;
}
//而这个时机就是当视图将要消失的时候，需要重写：
-(void)viewWillDisappear:(BOOL)animated{
if (self.returnTextBlock !=nil) {
self.returnTextBlock(self.tf.text);
NSLog(@"self.tf.text %@",self.tf.text);
}
}
@end
