TabBarViewController的创建以及渐变隐藏

//  CustomTabBarViewController.h

#import <UIKit/UIKit.h>
@interface CustomTabBarViewController : UITabBarController

+ (void)deallocTabbar;
+ (id)defaultsTabBar;

- (void)selectBUttonWithIndex:(NSInteger)index;
-(void)setTabBarHidden:(BOOL)Bool;
@end

//
//  CustomTabBarViewController.m
#import "CustomTabBarViewController.h"
#import "DJSHomeViewController.h"
#import "DJSStudioViewController.h"
#import "DJSAppointmentViewController.h"
#import "DJSMineViewController.h"
#import "Header.h"
#define btnBaseTag 100

static CustomTabBarViewController *defaults;
@interface CustomTabBarViewController ()
{
    BOOL tabBarIsShow;
}
@property (nonatomic, strong) UIImageView *baceGroundImage;
@property (nonatomic, strong) NSMutableArray *btnArray;

@end

@implementation CustomTabBarViewController
@synthesize baceGroundImage, btnArray;
+ (void)deallocTabbar
{
    defaults = nil;
}
+ (id)defaultsTabBar
{
    if (defaults == nil) {
        defaults = [[CustomTabBarViewController alloc] init];
    }
    return defaults;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    
    tabBarIsShow = YES;
    self.view.backgroundColor = [UIColor colorWithRed:242/255.0 green:242/255.0 blue:242/255.0 alpha:1];
    self.tabBar.hidden = YES;
    DJSHomeViewController *home = [[DJSHomeViewController alloc]init];
    UINavigationController *nav = [[UINavigationController alloc]initWithRootViewController:home];
    DJSStudioViewController *produce = [[DJSStudioViewController alloc]init];
    UINavigationController *nav1 = [[UINavigationController alloc] initWithRootViewController:produce];

    DJSAppointmentViewController *appoint = [[DJSAppointmentViewController alloc]init];
    UINavigationController *nav2 = [[UINavigationController alloc] initWithRootViewController:appoint];

    DJSMineViewController *mine = [[DJSMineViewController alloc]init];
    UINavigationController *nav3 = [[UINavigationController alloc] initWithRootViewController:mine];

    
    self.viewControllers = @[nav, nav1, nav2, nav3];
    
    btnArray = [[NSMutableArray alloc] init];
    [self setCustomTabbarItem];
}
- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
}
- (void)setCustomTabbarItem
{
    [btnArray removeAllObjects];
    baceGroundImage = [[UIImageView alloc] initWithFrame:CGRectMake(0, Main_height-54, Main_Width, 54)];
    baceGroundImage.backgroundColor = [UIColor whiteColor];

    baceGroundImage.image = [UIImage imageNamed:@"wireframe_bottom@2x"];
    baceGroundImage.userInteractionEnabled = YES;
    [self.view addSubview:baceGroundImage];
    
    
//    UIView *lineView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, Main_Width, 0.5)];
//    lineView.backgroundColor = [UIColor cyanColor];
//    [baceGroundImage addSubview:lineView];
    NSArray *imageNameArr = @[@"home_unicorn_unpress", @"home_project_unpress", @"home_studio_unpress",@"home_my_unpress"];
    NSArray *selecNameArr = @[@"home_unicorn_press", @"home_project_press", @"home_studio_press",@"home_my_press"];
    CGFloat space = Main_Width/4;
    for (NSInteger i = 0; i < 4; i++) {
        UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake(i * space, 0, space, 54)];
//        btn.backgroundColor = [UIColor cyanColor];
        [btn setImage:[UIImage imageNamed:imageNameArr[i]] forState:UIControlStateNormal];
        [btn setImage:[UIImage imageNamed:selecNameArr[i]] forState:UIControlStateSelected];
        btn.tag = btnBaseTag + i;
        if (i == 0)
        {
            btn.selected = YES;
        }
        [btn addTarget:self action:@selector(pressBtn:) forControlEvents:UIControlEventTouchUpInside];
        [baceGroundImage addSubview:btn];
        [btnArray addObject:btn];
    }
}
- (void)selectBUttonWithIndex:(NSInteger)index
{
    UIButton *btn = (UIButton *)btnArray[index];
    [self pressBtn:btn];
}

-(void)setTabBarHidden:(BOOL)Bool
{
    
    if (Bool) {
        [self hideTabBar];
    }
    else{
        [self showTabBar];
    }
}

- (void)hideTabBar {
    if (!tabBarIsShow)
    { //already hidden
        return;
    }
    [UIView animateWithDuration:0.35 animations:^{
        baceGroundImage.frame = CGRectMake(0, Main_height, Main_Width, 54);
    }];
    tabBarIsShow = NO;
}

- (void)showTabBar {
    if (tabBarIsShow)
    { // already showing
        return;
    }
    [UIView animateWithDuration:0.35 animations:^{
        baceGroundImage.frame = CGRectMake(0, Main_height-54, Main_Width, 54);
    }];

    tabBarIsShow = YES;
}

-(void)pressBtn:(id)sender
{
    UIButton *btn=(UIButton *)sender;
    
    if (btn.tag - btnBaseTag >= self.viewControllers.count) {
        return;
    }
    self.selectedIndex = btn.tag - btnBaseTag;
    for (UIButton *tempBtn in btnArray)
    {
        if (tempBtn.tag == btn.tag)
        {
            tempBtn.selected=YES;
        }
        else
        {
            tempBtn.selected=NO;
        }
    }
}
@end

1、创建

@interface AppDelegate ()
{
    CustomTabBarViewController *tabbar;
}

    tabbar=[CustomTabBarViewController defaultsTabBar];

    self.window.rootViewController = tabbar;
2、隐藏

    CustomTabBarViewController * tabBar =[CustomTabBarViewController defaultsTabBar];
    [tabBar setTabBarHidden:YES];