不调用委托方法(为零) [英] Delegate method is not called (is nil)

问题描述

已编辑我有带有 UIView 的 .xib 文件.UIView 包含一些元素和点击手势识别器.

EDITED I have .xib file with UIView. UIView contains some elements and tap gesture recognizer.

它通过插座连接到 AnnotationView.在 AnnotationView 中，我正在捕捉点击事件并且它工作正常.

It is connected to AnnotationView with outlets. In AnnotationView, I am catching tap events and it works fine.

然后我试图将此事件传递给我的父视图 (ViewController)，其中 AnnotationView 实例被创建并添加为子视图.但是我的委托方法没有被调用.我不知道，如何解决这个问题，也不知道是因为我在使用子视图还是我只是在委托上做错了什么.

Then I am trying to pass this event to my parent view (ViewController), where AnnotationView instance was created and added as subview. But my delegate method is not getting called. I don't know, how to solve this problem, and I don't know if it is because I am using subview or I am just doing something wrong with delegate.

这是一些代码:

AnnotationView.h

#import <UIKit/UIKit.h>

@protocol protName <NSObject>

-(void) test;

@end

@interface AnnotationView : UIView

@property (strong, nonatomic) IBOutlet UIImageView *image;
@property (weak, nonatomic) IBOutlet UILabel *textLabel;
@property (weak, nonatomic) IBOutlet UILabel *accessoryLabel;
@property (strong, nonatomic) IBOutlet UITapGestureRecognizer *tapRecognizer;
@property (nonatomic, weak) id <protName> delegate;

-(IBAction)handleTap:(UITapGestureRecognizer *)tapRecognizer;
@end

AnnotationView.m

#import "AnnotationView.h"

@implementation AnnotationView


- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
        NSArray *nibContents = [[NSBundle mainBundle] loadNibNamed:@"AnnotationView"
                                                             owner:self
                                                           options:nil];
        AnnotationView *_myView = [nibContents objectAtIndex:0];
        _myView.backgroundColor = [UIColor greenColor];
        [self addSubview: _myView];

    }
    return self;
 }

-(IBAction)handleTap:(UITapGestureRecognizer *)tapRecognizer{
    NSLog(@"tap tap");

    [self.delegate test]; //this delegate is nil
}

@end

ViewController.h

#import <UIKit/UIKit.h>
#import "AnnotationView.h"

@interface ViewController : UIViewController <protName>
@property (nonatomic,retain) AnnotationView *annot;

-(void) test;

@end

ViewController.m

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad
{
    _annot = [[AnnotationView alloc] initWithFrame:CGRectMake(100, 100, 212, 45)];
    _annot.textLabel.text = @"some text";
    _annot.delegate = self;
    [self.view addSubview:_annot];
}
-(void) viewWillAppear:(BOOL)animated{
    _annot.delegate = self;
}
-(void) test{
    NSLog(@"Delegate massage is received!");
}
@end

推荐答案

为什么不这样做:

@implementation ViewController

- (void)viewDidLoad
{
    CGRect frame = CGRectMake(100, 100, 212, 45)];
    NSArray *nibContents = [[NSBundle mainBundle] loadNibNamed:@"AnnotationView"
                                                         owner:nil
                                                       options:nil];
    for (id object in nibContents) {
        if ([object isKindOfClass:[AnnotationView class]]) {
            _annot = (AnnotationView *)object;
        }
    }        
    _annot.frame = frame;
    _annot.backgroundColor = [UIColor greenColor];
    _annot.textLabel.text = @"some text";
    _annot.delegate = self;
    [self.view addSubview:_annot];
}

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