delegate简单实现

Simulator Screen Shot 2016年10月20日 上午9.59.45.png

Simulator Screen Shot 2016年10月20日 上午9.59.51.png

如图，导航标题栏是一个自定义view，通过点击手势来切换不同的控制器。首先，来看下这个自定义view的实现：

#import 

@protocol SegmentedViewDelegate 

/**
 *  自定义segment的点击代理方法
 *
 *  @param index 选中按钮的index;
 */
- (void)selectAtIndex:(NSUInteger)index;

@end

@interface SegmentedView : UIImageView

@property(nonatomic,weak) id delegate;

@end

#import "SegmentedView.h"

@interface SegmentedView () {
    UIImageView *_leftView;
    UIImageView *_rightView;
    UILabel *_leftLabel;
    UILabel *_rightLabel;
}

@end

@implementation SegmentedView

- (id)init {
    if (self = [super init]) {
        [self prepareUI];
    }
    return self;
}

- (void)selectIndex:(NSUInteger)index {
    if (index == 0) {
        _leftView.image = [UIImage imageNamed:@"ZXselect_left"];
        _rightView.image = nil;
        _leftLabel.textColor = [UIColor whiteColor];
        _rightLabel.textColor = [UIColor blackColor];
        _leftLabel.userInteractionEnabled = NO;
        _rightLabel.userInteractionEnabled = YES;
    }
    else if (index == 1) {
        _leftView.image = nil;
        _rightView.image = [UIImage imageNamed:@"ZXselect_right"];
        _leftLabel.textColor = [UIColor blackColor];
        _rightLabel.textColor = [UIColor whiteColor];
        _leftLabel.userInteractionEnabled = YES;
        _rightLabel.userInteractionEnabled = NO;
    }
}

- (void)prepareUI {
    __weak SegmentedView *weakSelf = self;
    self.userInteractionEnabled = YES;
    self.image = [UIImage imageNamed:@"ZXselect_bg"];
    
    _leftView = [UIImageView new];
    _leftView.image = [UIImage imageNamed:@"ZXselect_left"];
    [self addSubview:_leftView];
    [_leftView mas_makeConstraints:^(MASConstraintMaker *make) {
        make.top.left.equalTo(weakSelf);
        make.width.equalTo(weakSelf).multipliedBy(0.5);
        make.height.equalTo(weakSelf);
    }];
    
    _rightView = [UIImageView new];
    [self addSubview:_rightView];
    [_rightView mas_makeConstraints:^(MASConstraintMaker *make) {
        make.top.right.equalTo(weakSelf);
        make.width.equalTo(weakSelf).multipliedBy(0.5);
        make.height.equalTo(weakSelf);
    }];
    
    _leftLabel = [UILabel new];
    _leftLabel.userInteractionEnabled = YES;
    _leftLabel.text = @"资讯";
    _leftLabel.textAlignment = NSTextAlignmentCenter;
    _leftLabel.textColor = [UIColor whiteColor];
    _leftLabel.font = [UIFont systemFontOfSize:14];
    [self addSubview:_leftLabel];
    [_leftLabel mas_makeConstraints:^(MASConstraintMaker *make) {
        make.top.left.bottom.right.equalTo(_leftView);
    }];
    UITapGestureRecognizer *tapL = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapSegmentedView:)];
    [_leftLabel addGestureRecognizer:tapL];
    
    _rightLabel = [UILabel new];
    _rightLabel.userInteractionEnabled = YES;
    _rightLabel.text = @"消息";
    _rightLabel.textAlignment = NSTextAlignmentCenter;
    _rightLabel.textColor = [UIColor blackColor];
    _rightLabel.font = [UIFont systemFontOfSize:14];
    [self addSubview:_rightLabel];
    [_rightLabel mas_makeConstraints:^(MASConstraintMaker *make) {
        make.top.left.bottom.right.equalTo(_rightView);
    }];
    UITapGestureRecognizer *tapR = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapSegmentedView:)];
    [_rightLabel addGestureRecognizer:tapR];
}

- (void)tapSegmentedView:(UITapGestureRecognizer *)tap {
    NSInteger index;
    if (tap.view == _leftView) {
        index = 0;
    }else{
        index = 1;
    }
    [self selectIndex:index];
    if (_delegate && [_delegate respondsToSelector:@selector(selectAtIndex:)]) {
        [_delegate selectAtIndex:index];
    }
}

在控制器中，实现代理方法。控制器.m文件：

#import "InformationController.h"
#import "SegmentedView.h"
#import "InfoChildController.h"
#import "MessageChildController.h"
#import "UITabBarController+HideTabBar.h"

@interface InformationController ()  {
    SegmentedView *_segmentedView;
    InfoChildController *_infoChildController;
    MessageChildController *_messageChildController;
}

@end

@implementation InformationController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    self.fd_prefersNavigationBarHidden = NO;
    [self prepareNavigationBar];
    [self prepareChildViewController];
}

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    [self.tabBarController setTabBarHidden:NO myClass:self];
}

- (void)prepareNavigationBar {
    self.navigationItem.leftBarButtonItem = nil;
    _segmentedView = [[SegmentedView alloc] init];
    _segmentedView.delegate = self;
    _segmentedView.bounds = CGRectMake(0, 0, 210, 25);
    self.navigationItem.titleView = _segmentedView;
}

- (void)prepareChildViewController {
    _infoChildController = [[InfoChildController alloc] init];
    [self addChildViewController:_infoChildController];
    [self.view addSubview:_infoChildController.view];
    _messageChildController = [[MessageChildController alloc] init];
    [self addChildViewController:_messageChildController];
    [self.view addSubview:_messageChildController.view];
    _messageChildController.view.hidden = YES;
}

#pragma mark - SegmentedViewDelegate
- (void)selectAtIndex:(NSUInteger)index {
    if (index == 0) {
        _infoChildController.view.hidden = NO;
        _messageChildController.view.hidden = YES;
    }
    else {
        _infoChildController.view.hidden = YES;
        _messageChildController.view.hidden = NO;
    }
}

@end