关于NavigationBar背景图片和颜色的设置

第一种：直接在你的UIViewController中设置

//颜色设置，采用RGB格式

UIColor *bgcolor = [UIColorcolorWithRed:255.0f/255.0f green:0.0f/255.0f blue:0.0f/255.0f alpha:1.0f];

self.navigationController.navigationBar.tintColor = bicolor;

//设置navigationBar的背景图片

UIImage *navBarImage = [UIImageimageNamed:@"banner1.jpg"];

navigationbaritembackgroundView=[[UIImageViewalloc] initWithImage:navBarImage];

[self.navigationController.navigationBarinsertSubview:navigationbaritembackgroundViewatIndex:1];//将背景图片设置在你想要的atIndex处

[self.navigationController.navigationBar adduSubview:navigationbaritembackgroundView];//这条指令将会让背景图片出现在最顶层，如果你开始在navigationBar设置得有其它的ui控件的话，它们将会被覆盖隐藏掉；

上面的图片是直接加进去的，无法调整图片的大小，那么你的图片最好先制作为适合你预期的效果样式

第二种：扩展UINavigationBar

这里我先给链接，http://wsqwsq000.iteye.com/blog/1145172

这个我认为说得是最清楚的

what?不知道怎么扩展，那么看下面

选中UINavigationBar，然后命名你想要的名称

添加完成后，出现两个文件

后然在这个类中进行添加函数，后面的看那个链接

 //CustomNavigationBar.h
 @interface UINavigationBar (UINavigationBarCategory)
 UIImageView *backgroundView;
 - (void)setBackgroundImage:(UIImage*)image;
 - (void)insertSubview:(UIView *)view atIndex:(NSInteger)index;
 @end

 //CustomNavigationBar.m
 @implementation UINavigationBar (UINavigationBarCategory)
 -(void)setBackgroundImage:(UIImage*)image
 {
     if(image == nil)
     {
         [backgroundView removeFromSuperview];
     }
     else
     {
         backgroundView = [[UIImageView alloc] initWithImage:image];
         backgroundView.tag = 1;
         backgroundView.frame = CGRectMake(0.f, 0.f, self.frame.size.width, self.frame.size.height);
         backgroundView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
         [self addSubview:backgroundView];
         [self sendSubviewToBack:backgroundView];
         [backgroundView release];
     }
 }

 //for other views
 - (void)insertSubview:(UIView *)view atIndex:(NSInteger)index
 {
     [super insertSubview:view atIndex:index];
     [self sendSubviewToBack:backgroundView];
 }
 @end

 //YourViewController.m
 - (void)viewWillAppear:(BOOL)animated
 {
     [super viewWillAppear:animated];
     [self.navigationController.navigationBar
         setBackgroundImage:[UIImage imageNamed:@"navigation_bar_bg.png"]];
 }

综合了网上其它一些方法，有些没测试出效果

#import <UIKit/UIKit.h>

@interface UINavigationBar (CustomImage)
- (void)setBackgroundImage:(UIImage*)image;
@end

#import "UINavigationBar+CustomImage.h"
UIImageView *backgroundView; 
@implementation UINavigationBar (CustomImage)
- (void)setBackgroundImage:(UIImage*)image
{
    if(image == nil)  
    {  
        UIColor *bgcolor = [UIColor colorWithRed:46.0f/255.0f green:87.0f/255.0f blue:29.0f/255.0f alpha:1.0f];
        self.tintColor = bgcolor;
        [backgroundView removeFromSuperview];  
    }  
    else  
    {  
        backgroundView = [[UIImageView alloc] initWithImage:image];  
        //backgroundView.tag = 1;  
        backgroundView.frame = CGRectMake(0.f, 0.f, self.frame.size.width, self.frame.size.height);  
        backgroundView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;  
        [self insertSubview:backgroundView atIndex:1];//这条指令atIndex：1达到了预期的效果
        [backgroundView release];  
    }  
}

/*
- (void)drawRect:(BOOL)color { 
    //颜色填充
    if(color==YES )
    {
        UIColor *bgcolor = [UIColor colorWithRed:46.0f/255.0f green:87.0f/255.0f blue:29.0f/255.0f alpha:1.0f];
        self.tintColor = bgcolor;
        return;
    }
    UIImageView *backgroundView; 
    UIImage *navBarImage = [UIImage imageNamed:@"banner1.jpg"];
    
    backgroundView = [[UIImageView alloc] initWithImage:navBarImage]; 
    [self insertSubview:backgroundView atIndex:1];//这条指令atIndex：1达到了预期的效果 
    [backgroundView release];
    
    /*
    //第一种：颜色填充
    	UIColor *color = [UIColor blueColor];
    	CGContextRef context = UIGraphicsGetCurrentContext();
    	CGContextSetFillColor(context, CGColorGetComponents( [color CGColor]));
    	CGContextFillRect(context, rect);
    	self.tintColor = color;
    */
    
	//第二种：图片填充
    /*
	UIImage *img	= [UIImage imageNamed: @"net.png"];
	[img drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];	
     */
    /*第三种：
    UIImage *img = [UIImage imageNamed: @"net.png"];
    CGPoint point = {0,0};
    [img drawAtPoint:point];
     */
    
    //[self addSubview:backgroundView]; 这条指令addSubview：会让背景图显示在最前面，覆盖掉工程里的搜索按钮 
    //[self sendSubviewToBack:backgroundView];这条指令加上在这个工程里背景图就无法显示了
    
    //第四种：加入旋转坐标系代码
    // Drawing code
    /*
     CGContextRef context = UIGraphicsGetCurrentContext();
     CGContextTranslateCTM(context, 0.0, self.frame.size.height);
     CGContextScaleCTM(context, 1.0, -1.0);
     CGPoint center=self.center;
     
     CGImageRef cgImage= CGImageCreateWithImageInRect(navBarImage.CGImage,CGRectMake(0, 0, 1, 44));
     CGContextDrawImage(context, CGRectMake(center.x-160-80, 0, 80,self.frame.size.height), cgImage);
     CGContextDrawImage(context, CGRectMake(center.x-160, 0, 320,self.frame.size.height), navBarImage.CGImage);
     CGContextDrawImage(context, CGRectMake(center.x+160, 0, 80,self.frame.size.height), cgImage);
    
} 
 */
@end