將方法從ViewController復制到AppDelegate-NULL

Question

您好，我嘗試將輸入從ViewController中的文本字段復制到AppDelegate。 不，反之亦然。

當我嘗試這樣做時，我NSLog給了我這個：

StruktonTest[8467:11603] (null)

順便說一句，StruktonTest是我的Testapp的名稱。

這是我在ViewController中獲取文本的代碼：

if ([[[self m_textfield] text] length] == 10) {
m_textfield.text=[NSString stringWithFormat:@"%@", m_textfield.text];
NSLog(@"%@", m_textfield.text);
telefoonnummer = m_textfield.text;

我將其復制到我的AppDelegate.h文件中，如下所示：

@interface  LocationDelegate : NSObject <CLLocationManagerDelegate> 
{
UILabel * resultsLabel;
NSString *phonenumber;


}

- (id) initWithLabel:(UILabel*)label;
-(id)initWithDictionary:(NSDictionary *)dict;
-(id)initWithName:(NSString *)aName;
-(NSDictionary *)toDictionary;

@property (nonatomic , retain) NSString *phonenumber;

這是我來自ViewController的代碼，也許我在這里犯了錯誤：

@interface LocationTestViewController : UIViewController <CLLocationManagerDelegate> {
IBOutlet UILabel * m_significantResultsLabel;
IBOutlet UISwitch * m_significantSwitch;
IBOutlet UISwitch * m_mapSwitch;
IBOutlet MKMapView * m_map;
IBOutlet UITextField * m_textfield;
NSString *String;
IBOutlet UILabel * mobielnummer;
IBOutlet UILabel * deellocatie;
IBOutlet UILabel * welldone;
IBOutlet UILabel * locatiemaps;
IBOutlet UILabel * mapslocatie;
NSString *telefoonnummer;



LocationDelegate * m_significantDelegate;

// location objects
CLLocationManager* m_gpsManager;
CLLocationManager* m_significantManager;
}

-(IBAction) actionSignificant:(id)sender;
-(IBAction) actionMap:(id)sender;
-(IBAction) actionLog:(id)sender;
-(IBAction)changrGreeting ;



@property (retain, nonatomic) IBOutlet UILabel * m_significantResultsLabel;
@property (retain, nonatomic) IBOutlet UISwitch * m_significantSwitch;
@property (retain, nonatomic) IBOutlet UISwitch * m_mapSwitch;
@property (retain, nonatomic) IBOutlet MKMapView * m_map;
@property (nonatomic ,retain) IBOutlet UITextField *m_textfield;
@property (nonatomic, copy) IBOutlet NSString *String;
@property (nonatomic, retain) IBOutlet UILabel  *mobielnummer;
@property (nonatomic, retain) IBOutlet UILabel  *deellocatie;
@property (nonatomic, retain) IBOutlet UILabel  *welldone;
@property (nonatomic, retain) IBOutlet UILabel  *locatiemaps;
@property (nonatomic, retain) IBOutlet UILabel  *mapslocatie;
@property (nonatomic , retain) NSString *telefoonnummer;



@end

這是我的AppDelegate.m中的代碼

LocationTestViewController*locationTestViewController = [[LocationTestViewController   alloc]init];
phonenumber = locationTestViewController.telefoonnummer;
NSLog(@"%@", phonenumber);

所以我在復制此內容時會收到NULL。 有誰知道如何解決這個問題。 將不勝感激。

Answer 1

這段代碼：

LocationTestViewController*locationTestViewController = [[LocationTestViewController   alloc]init];
phonenumber = locationTestViewController.telefoonnummer;
NSLog(@"%@", phonenumber);

正在創建LocationTestViewController的新實例，然后讀取.telefoonnummer字段，該字段顯然為空。

當然，您可以使用ViewController將字段“提供”給AppDelegete來代替AppDelegate的“讀取”字段嗎？

您可以將NSUserDefaults用作臨時存儲，或在ViewController中使用如下代碼：

YourAppDelegate *appDelegate = (YourAppDelegate *)[[UIApplication sharedApplication] delegate];
appDelegate.phoneNumber = self.telefoonnummer;