iOS中使用block传值

MainView.h

#import <UIKit/UIKit.h>

@interface MainView : UIViewController

{

IBOutlet UIButton* btn;

IBOutlet UILabel* labShow;

}

-(IBAction)push:(id)sender;

@end

MainView.m

#import "MainView.h"

#import "SecondView.h"

@implementation MainView

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil

{

self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];

if (self) {

}

return self;

}

- (void)didReceiveMemoryWarning

{

[super didReceiveMemoryWarning];

}

#pragma mark - View lifecycle

- (void)viewDidLoad

{

[super viewDidLoad];

}

-(IBAction)push:(id)sender

{

SecondView *s = [[SecondView alloc] initwithBlock:Block_copy(^(NSString *str){

NSLog(@"%@",str);

labShow.text = str;

})];

[self.navigationController pushViewController:s  animated:YES];

[s release];

}

- (void)viewDidUnload

{

[super viewDidUnload];

}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation

{

return (interfaceOrientation == UIInterfaceOrientationPortrait);

}

@end

Second.h

#import <UIKit/UIKit.h>

typedef void (^MyBlock)(NSString *);

@interface SecondView : UIViewController

{

IBOutlet UITextField* txtView;

MyBlock my;

}

-(IBAction)back:(id)sender;

-(id)initwithBlock:(MyBlock)str;

@end

Second.m

#import "SecondView.h"

@implementation SecondView

-(id)initwithBlock:(MyBlock)str

{

self = [super init];

if(self)

{

my = str;

}

return self;

}

-(IBAction)back:(id)sender

{

NSString* s = txtView.text;

if(my)

{

my(s);

}

[self.navigationController popViewControllerAnimated:YES];

}

- (void)didReceiveMemoryWarning

{

[super didReceiveMemoryWarning];

}

-(void)dealloc{

Block_release(my);

[super dealloc];

}

#pragma mark - View lifecycle

- (void)viewDidLoad

{

[super viewDidLoad];

}

- (void)viewDidUnload

{

[super viewDidUnload];

}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation

{

return (interfaceOrientation == UIInterfaceOrientationPortrait);

}

@end