问题
I have two view controllers: BSViewController which contains the source ivars number and array, and BSotherViewController which as the target needs to receive the ivars . (BSViewController has a button on it that is segues to BSotherViewController.)
How can I access the value of the two ivars in BSotherViewController?
BSViewController.h
#import <UIKit/UIKit.h>
@interface BSViewController : UIViewController
@property (nonatomic) NSInteger number;
@property (nonatomic, weak) NSArray * array;
@end
BSViewController.m
#import "BSViewController.h"
@interface BSViewController ()
@end
@implementation BSViewController
@synthesize number;
@synthesize array;
- (void)viewDidLoad
{
[super viewDidLoad];
BSViewController *view = [[BSViewController alloc] init];
NSArray* _array = [NSArray arrayWithObjects: @"manny",@"moe",nil];
view.array = _array;
view.number = 25;
}
@end
BSotherViewController.h
#import <UIKit/UIKit.h>
@class BSViewController;
@interface BSotherViewController : UIViewController
@end
BSotherViewController.m
The problem below is that aview.number is 0, not 25; and aview.array is null.
#import "BSotherViewController.h"
#include "BSViewController.h"
@interface BSotherViewController ()
@end
@implementation BSotherViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
BSViewController *aview = [[BSViewController alloc] init];
NSLog(@"other view: %@", aview);
NSLog(@"other number: %d", aview.number); // produces 0, not desired 25
NSLog(@"other array: %@", aview.array); // produces null, not desired manny,moe
}
@end
回答1:
When you instantiate the BSViewController from BSOtherViewController you are calling the init method. The values is set in viewDidLoad in BSViewController, and that method won't be invoked until the view is actually loaded.
Try to override the init method and set the values
- (id)init {
if (self = [super init]) {
//Set values
NSArray* _array = [NSArray arrayWithObjects: @"manny",@"moe",nil];
self.array = _array;
self.number = 25;
}
return self;
}
回答2:
Replace your BSViewController viewDidLoad method with init like this :
- (id)init {
if (self = [super init]) {
NSArray* _array = [NSArray arrayWithObjects: @"manny",@"moe",nil];
self.array = _array;
view.number = 25;
}
return self;
}
来源：https://stackoverflow.com/questions/15360290/receive-ivar-in-other-class