iOS自定义导航栏形状

很多时候，系统自带的导航不能满足我们的项目需求，我们需要自定，来满足需求。
主要代码：
baseNavigationViewController.h

#import <UIKit/UIKit.h>@interface baseNavigationViewController : UINavigationController@end

baseNavigationViewController.m

#import "baseNavigationViewController.h"#import "SecondViewController.h"@interface baseNavigationViewController ()@end@implementation baseNavigationViewController- (void)viewDidLoad {    [super viewDidLoad];    [self loadThemeImage];    [self customNavigationBar];}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}- (void)loadThemeImage{    UIImage *image = [UIImage imageNamed:@"top_bar_bkg_6"];    [self.navigationBar setBackgroundImage:image                             forBarMetrics:UIBarMetricsDefault];////    UIButton *buton = [[UIButton alloc]initWithFrame:CGRectMake(5, 0, 60, 44)];////    buton.backgroundColor = [UIColor colorWithRed:0.2955 green:0.2599 blue:1.0 alpha:1.0];////    [buton setTitle:@"点击" forState:UIControlStateNormal];////    [buton setTitle:@"ok" forState:UIControlStateHighlighted];////    buton.layer.cornerRadius = 5;//    buton.layer.masksToBounds = YES;//    [buton addTarget:self action:@selector(click:) forControlEvents:UIControlEventTouchUpInside];//    [self.navigationBar addSubview:buton];}-(void)click:(UIButton *)b{    SecondViewController *sec = [[SecondViewController alloc]init];    [self pushViewController:sec animated:YES];}- (void)customNavigationBar {    if ([self respondsToSelector:@selector(setBackgroundImage:forBarMetrics:)]) {        [self.navigationBar setBackgroundImage:[UIImage imageNamed:@"Title"] forBarMetrics:UIBarMetricsDefault];    } else {        [self drawRect:self.navigationBar.bounds];    }    [self drawRoundCornerAndShadow];}- (void)drawRect:(CGRect)rect {    [[UIImage imageNamed:@"Title"] drawInRect:rect];}- (void)drawRoundCornerAndShadow {    CGRect bounds = self.navigationBar.bounds;    bounds.size.height +=10;    UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:bounds                                                   byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerTopRight)                                                         cornerRadii:CGSizeMake(10.0, 10.0)];    CAShapeLayer *maskLayer = [CAShapeLayer layer];    maskLayer.frame = bounds;    maskLayer.path = maskPath.CGPath;    [self.navigationBar.layer addSublayer:maskLayer];     self.navigationBar.layer.mask = maskLayer;     self.navigationBar.layer.shadowOffset = CGSizeMake(3, 3);    self.navigationBar.layer.shadowOpacity = 0.7;    self.navigationBar.layer.shadowPath = [UIBezierPath bezierPathWithRect:self.navigationBar.bounds].CGPath;}@end

RootViewController.m

#import "RootViewController.h"@interface RootViewController ()@end@implementation RootViewController- (void)viewDidLoad {    [super viewDidLoad];    self.title = @"自定义导航栏";    UIBarButtonItem *menu = [[UIBarButtonItem alloc]initWithTitle:@"xsac" style:UIBarButtonItemStylePlain target:self action:@selector(click)];    self.navigationItem.rightBarButtonItem = menu;    UISegmentedControl *SegmentedControl = [[UISegmentedControl alloc] initWithItems:                                            [NSArray arrayWithObjects:                                             @"笑话",                                             @"论坛",                                             @"段子",nil]];    [SegmentedControl addTarget:self action:@selector(clicks:)               forControlEvents:UIControlEventValueChanged];    SegmentedControl.frame = CGRectMake(0, 0, 80, 30);    SegmentedControl.momentary = YES;    SegmentedControl.tintColor = [UIColor purpleColor];    self.navigationItem.titleView =SegmentedControl;}-(void)clicks:(UISegmentedControl *)seg{    switch (seg.selectedSegmentIndex) {        case 0:            NSLog(@"111111");            break;        case 1:            NSLog(@"222222");            break;        case 2:           NSLog(@"3333333");            break;        default:            break;    }}-(void)click{    NSLog(@"cdcds");}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}/*#pragma mark - Navigation// In a storyboard-based application, you will often want to do a little preparation before navigation- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {    // Get the new view controller using [segue destinationViewController].    // Pass the selected object to the new view controller.}*/@end

效果图