如何將值傳遞給另一個viewcontroller？

Question

大家好，我有一個UITableView在UIViewController。當表格中的一行被點擊時，我正在收集單元格的文本值並將其放入一個名爲localstringGValue的字符串中。

我想通過此串，而在另一個顯示它，viewController，但不使用-pushViewController：我想這個值要被存儲像NSUserDefaults或NSDictonary然後某處，另一方面視圖控制器viewWillapper我想該存儲值以標籤顯示。

在我.h：

NSString *localStringGValue; 

在我.m：

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { 
    [tableView deselectRowAtIndexPath:indexPath animated:YES]; 

    localStringGValue = [tableView cellForRowAtIndexPath:indexPath].textLabel.text; 
} 

我在其他視圖控制器：

-(void)viewWillAppear 
{ 
    label.text=localStringGValue; 
} 

在此先感謝。

Answer 1

保存到NSUserDefaults的：

[[NSUserDefaults standardUserDefaults] setObject:localstringGValue forKey:@"localstringGValue"]; 
[[NSUserDefaults standardUserDefaults] synchronize]; 

從檢索NSUserDefaults的：

NString *localstringGValue = [[NSUserDefaults standardUserDefaults] objectForKey:@"localstringGValue"]; 

Answer 2

爲什麼不申報@property(nonatomic,retain)和@synthesize呢？然後getters/setters將被自動創建。否則，自己定義一些getter/setter。

Answer 3

只需使用delegate。在推送'UploadViewController'實例之前，您需要將其設置爲delegate，並將其設置爲self（位於GoogleDocMainPageController.m中）。

[self.delegate setDataAfterSelectedTabelCell:[NSString stringWithFormat:@"TalbeCell %d selected", [indexPath row]]]; 

主代碼如下所示：每次的TABEL小區被選擇，它會爲self.delegate通過分派self.delegate的方法，該方法是通過GoogleDocMainPageController實現設定值（這裏是GoogleDocMainPageController實例）
UploadViewController.h：

#import <UIKit/UIKit.h> 

@class UploadViewController; 

@protocol UploadViewControllerDelegate <NSObject> 

- (void)setDataAfterSelectedTabelCell:(NSString *)stringValueInCell; 

@end 

@interface UploadViewController : UITableViewController 

@property (nonatomic, retain) id <UploadViewControllerDelegate> delegate; 

@end 

UploadViewController.m：

//... 
@synthesize delegate = _delegate; 

//... 
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath 
{ 
    [self.delegate setDataAfterSelectedTabelCell:[NSString stringWithFormat:@"TalbeCell %d selected", [indexPath row]]]; 
} 

GoogleDocMainPageController.h：

#import <UIKit/UIKit.h> 

#import "UploadViewController.h" 

@class UploadViewController; 

@interface GoogleDocMainPageController : UIViewController <UploadViewControllerDelegate> 

- (void)loadUploadViewController; 

@property (nonatomic, retain) UILabel * glLabel; 
@property (nonatomic, retain) UploadViewController * uploadViewController; 

@end 

GoogleDocMainPageController.m：

//... 
@synthesize glLabel = _glLabel; 
@synthesize uploadViewController = _uploadViewController; 

//... 
- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 

    UIButton * uploadButton = [[UIButton alloc] initWithFrame:CGRectMake(10.0f, 160.0f, 300.0f, 35.0f)]; 
    [uploadButton setBackgroundColor:[UIColor blackColor]]; 
    [uploadButton setTitle:@"Upload Button" forState:UIControlStateNormal]; 
    [uploadButton addTarget:self action:@selector(loadUploadViewController) forControlEvents:UIControlEventTouchUpInside]; 
    [self.view addSubview:uploadButton]; 
    [uploadButton release]; 

    self.glLabel = [[UILabel alloc] initWithFrame:CGRectMake(10.0f, 200.0f, 300.0f, 35.0f)]; 
    [self.glLabel setBackgroundColor:[UIColor blackColor]]; 
    [self.glLabel setTextColor:[UIColor whiteColor]]; 
    [self.glLabel setTextAlignment:UITextAlignmentCenter]; 
    [self.glLabel setText:@"Default"]; 
    [self.view addSubview:self.glLabel]; 

    self.uploadViewController = [[UploadViewController alloc] initWithStyle:UITableViewStylePlain]; 
} 

//... 
#pragma mark - 

- (void)loadUploadViewController 
{ 
    [self.uploadViewController setDelegate:self]; 
    [self.navigationController pushViewController:self.uploadViewController animated:YES]; 
} 

#pragma mark - UploadViewControllerDelegate 

- (void)setDataAfterSelectedTabelCell:(NSString *)stringValueInCell 
{ 
    [self.glLabel setText:stringValueInCell]; 
} 

Answer 4

通過FOL去降脂步驟 -

在首先的ViewController -

1. 創建第二視圖控制器 像SecondViewController *秒= [[SecondViewController的alloc] INIT]的對象; 秒。myLable = @「My Lable String」;

   在第二的ViewController -

2. 在.h文件中 UILable * myLable;

   @property（nonautomic，retain）IBOutlet UILable * myLable;

   2.In.m文件 @synthesize myLable;