單例傳值 ------- 如果頁面之間相隔很多,要進行傳值,將值保存到第三方,將第三方設置爲單例模式
代碼如下:
[objc] view plaincopy
<pre name="code" class="objc">#import <Foundation/Foundation.h>
@interface Singleton : NSObject
+ (Singleton *)shareSingleton;
@property (nonatomic,copy)NSString * text;
@end
[objc] view plaincopy
#import "Singleton.h"
@implementation Singleton
static Singleton * singleton = nil;
+ (Singleton *)shareSingleton
{
@synchronized(self){
if (singleton == nil) {
singleton = [[Singleton alloc]init];
}
}
return singleton;
}
@end
[objc] view plaincopy
#import "FirstViewController.h"
#import "SecondViewController.h"
#import "UIButton+Create.h"
#import "Singleton.h"
@interface FirstViewController ()
{
UITextField * _textField;//創建一個輸入框
}
@end
@implementation FirstViewController
- (void)dealloc
{
[_textField release];
[super dealloc];
}
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
self.view.backgroundColor = [UIColor redColor];
self.navigationItem.title = @"首頁";
/**
* 1.在第一個界面創建一個輸入框
*
*/
_textField = [[UITextField alloc]initWithFrame:CGRectMake(50, 80, 200, 30)];
_textField.borderStyle = UITextBorderStyleRoundedRect;
[self.view addSubview:_textField];
/**
* 1.創建一個UIButton,
* 2.並添加響應事件,從首頁跳轉到第二個頁面.
*/
UIButton * button = [UIButton systemButtonWithFrame:CGRectMake(100, 120, 50, 50) title:@"Push" target:self action:@selector(didClickButtonAction)];
[self.view addSubview:button];
// Do any additional setup after loading the view.
}
- (void)didClickButtonAction
{
/**
* 1.用push的方法推出下一個頁面
* 2.把首頁輸入框輸入的字符串,通過單例來接收
* 3.從而實現把首頁輸入框輸入的字符串,傳到第二頁的UILabel上.
*/
SecondViewController * secondVC = [[SecondViewController alloc]init];
[Singleton shareSingleton].text = _textField.text;
[self.navigationController pushViewController:secondVC animated:YES];
[secondVC release];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
[objc] view plaincopy
#import "SecondViewController.h"
#import "Singleton.h"
@interface SecondViewController ()
@end
@implementation SecondViewController
- (void)dealloc
{
[_label release];
[super dealloc];
}
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
self.view.backgroundColor = [UIColor orangeColor];
self.navigationItem.title = @"第二頁";
/**
* 1.在第二個界面創建一個UILabel
* 2.把首頁輸入框輸入的字符串,通過單例類的屬性NSString * text接收
* 3.然後通過賦值給UILabel
*/
_label = [[UILabel alloc]initWithFrame:CGRectMake(50, 80, 200, 30)];
_label.backgroundColor = [UIColor greenColor];
_label.text = [Singleton shareSingleton].text;
[self.view addSubview:_label];
// Do any additional setup after loading the view.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end