如何为UINavigationBar设置背景图片

//////////////////////////////////////////////////////////* input: The image and a tag to later identify the view */@implementation UINavigationBar (CustomImage)- (void)drawRect:(CGRect)rect {UIImage *image = [UIImage imageNamed: @"title_bg.png"];[image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];}@end/////////////////////////////////////////////////////////@implementation FriendsPageViewController// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.- (void)viewDidLoad {self.navigationBar.tintColor = [UIColor purpleColor];[self initWithRootViewController:[[RegPageViewController alloc] init]];    [super viewDidLoad];}......

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实现的效果如下图:

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