Tabbar的隐藏动画及按钮的切换动画效果

首先创建一个集成于UITabBarController子类控制器,然后实现UITabBar这个代理方法:-(void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item 完成按钮切换的动画效果;
自定义了两个类方法实现tabbar的隐藏显示的动画效果;
代码如下:

.h

#import <UIKit/UIKit.h>

@interface CYTabBarViewController : UITabBarController
//隐藏显示tabbar
+ (void)setTabBarHidden:(BOOL)hidden TabBarVC:(UITabBarController*)tabbarVC
@end

.m

#import "CYTabBarViewController.h"

#define kDevice_Is_iPhoneX ([UIScreen instancesRespondToSelector:@selector(currentMode)] ? CGSizeEqualToSize(CGSizeMake(1125, 2436), [[UIScreen mainScreen] currentMode].size) : NO)

@interface CYTabBarViewController ()
@property(nonatomic,assign) NSInteger index;
@end

@implementation CYTabBarViewController

- (void)viewDidLoad {
    [super viewDidLoad];

}
-(void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item{
    NSInteger index = [self.tabBar.items indexOfObject:item];
    if (index != _index) {
        //执行动画
        NSMutableArray *arry = [NSMutableArray array];
        for (UIView *btn in self.tabBar.subviews) {
            if ([btn isKindOfClass:NSClassFromString(@"UITabBarButton")]) {
                [arry addObject:btn];
                
            }
        }
        if(arry == nil || arry.count == 0){
            return;
        }
        // 控制器如果这么写标题 self.title = @"aaa"; 这个会同时改变 navigationController的title 和 tabBarItem的title,而且tabBarButton的对象也发生了改变(遍历的UITabBarButton顺序可能发生改变了)。所以保险起见 在此加个排序。
        for (int i = 1; i < arry.count; i++) {
            for (int j = 0; j < arry.count - i; j++) {
                int x0 = [arry[j]frame].origin.x;
                int x1 = [arry[j+1]frame].origin.x;
                if (x0>x1) {
                    [arry exchangeObjectAtIndex:j withObjectAtIndex:j+1];
                }
                
            }
        }
        
        CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"transform.scale"];
        //速度控制函数
        animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
        animation.repeatCount = 1;      //次数
        animation.duration = 0.25;       //时间
        animation.fromValue = [NSNumber numberWithFloat:0.8];   //伸缩倍数
        animation.toValue = [NSNumber numberWithFloat:1];     //结束伸缩倍数
        [[arry[index] layer] addAnimation:animation forKey:nil];
        //记录当前的显示的Tabbar的index
        _index = index;
    }
}



//隐藏显示tabbar
+ (void)setTabBarHidden:(BOOL)hidden TabBarVC:(UITabBarController*)tabbarVC

{
    //打印的数据为 iPhone7 测试
    
    UIView *tab = tabbarVC.view; //UILayoutContainerView: 0x145d10390; frame = (0 0; 375 667);
    
    CGRect tabRect = tabbarVC.tabBar.frame;//tabRect = (origin = (x = 0, y = 618), size = (width = 375, height = 49))
    
    if ([tab.subviews count] < 2) {// tab.subviews[0] = UITransitionView ;  tab.subviews[1] = UITabbar
        
        return;
        
    }
    
    UIView *view; //UITransitionView  frame 等于 全屏
    
    if ([[tab.subviews objectAtIndex:0] isKindOfClass:[UITabBar class]]) {
        
        view = [tab.subviews objectAtIndex:1];
        
    } else {
        
        view = [tab.subviews objectAtIndex:0];
        
    }
    
    
    if (hidden) {
        //隐藏
        view.frame = tab.bounds;
        
        tabRect.origin.y=[[UIScreen mainScreen]bounds].size.height+tabbarVC.tabBar.frame.size.height;
        
    } else {
        //显示
        view.frame = CGRectMake(tab.bounds.origin.x, tab.bounds.origin.y, tab.bounds.size.width, tab.bounds.size.height);
        
        tabRect.origin.y=[[UIScreen mainScreen] bounds].size.height-tabbarVC.tabBar.frame.size.height;
        
    }
    
    
    [UIView animateWithDuration:0.3f animations:^{
        
        tabbarVC.tabBar.frame=tabRect;
        
    }completion:^(BOOL finished) {
        
    }];
    
}
@end

ps:关于self.title的问题我在这篇里有介绍:传送门

调用代码如下:

 //显示
    [CYTabBarViewController setTabBarHidden:NO TabBarVC:self.tabBarController];
}
//隐藏
    [CYTabBarViewController setTabBarHidden:YES TabBarVC:self.tabBarController];
}
@end