导航视图的背景图像

Question

我在正确显示导航视图的背景图像时遇到问题.这是图片:

这是代码:

- (id)initWithStyle:(UITableViewStyle)style {
    if (self = [super initWithStyle:style]) {

        UIImage *image = [UIImage imageNamed: @"bg_table_active.png"];
        UIImageView *imageview = [[UIImageView alloc] initWithImage: image];
        UIBarButtonItem *addButton = [[UIBarButtonItem alloc]
                                       initWithTitle:NSLocalizedString(@"Settings", @"")
                                       style:UIBarButtonItemStyleDone
                                       target:self
                                       action:@selector(GoToSettings)];
        self.navigationItem.titleView = imageview;
        self.navigationItem.rightBarButtonItem = addButton;
        self.navigationItem.hidesBackButton = TRUE;
    }
    return self;
}

如何将图片拉伸到整个导航视图？

Answer 1

我在我的应用程序中这样做.在AppDelegate中我有这个代码:

@implementation UINavigationBar (CustomImage)
- (void)drawRect:(CGRect)rect
{
  UIImage *image = [UIImage imageNamed: @"custom_nav_bar.png"];
  [image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
}
@end

Answer 2

我修改了Mike Rundle的版本,以便在必要时设置自定义图像.我还合并了40lb-suit-of-bees建议的改变.初始化期间需要调用initImageDictionary:

//UINavigationBar+CustomImage.h
#import <Foundation/Foundation.h>

@interface UINavigationBar(CustomImage)
+ (void) initImageDictionary;
- (void) drawRect:(CGRect)rect;
- (void) setImage:(UIImage*)image;
@end


//UINavigationBar+CustomImage.m    
#import "UINavigationBar+CustomImage.h"
//Global dictionary for recording background image
static NSMutableDictionary *navigationBarImages = NULL;

@implementation UINavigationBar(CustomImage)
//Overrider to draw a custom image

+ (void)initImageDictionary
{
    if(navigationBarImages==NULL){
        navigationBarImages=[[NSMutableDictionary alloc] init];
    }   
}

- (void)drawRect:(CGRect)rect
{
    NSString *imageName=[navigationBarImages objectForKey:[NSValue valueWithNonretainedObject: self]];
    if (imageName==nil) {
        imageName=@"header_bg.png";
    }
    UIImage *image = [UIImage imageNamed: imageName];
    [image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
}

//Allow the setting of an image for the navigation bar
- (void)setImage:(UIImage*)image
{
    [navigationBarImages setObject:image forKey:[NSValue valueWithNonretainedObject: self]];
}
@end