Iphone 为选项卡栏设置背景图像

我正在尝试以编程方式为我的应用程序中的选项卡栏设置背景图像。我的代码如下：

RootViewController.h

IBOutlet UITabBar *mainTabBar;
    IBOutlet UITabBarItem *settingsBarItem;
    IBOutlet UITabBarItem *infoBarItem;
    IBOutlet UITabBarItem *aboutBarItem;

#import <UIKit/UIKit.h>

@interface CustomTabBarController : UITabBarController {
    UIButton *settingsButton;
    UIButton *infoButton;
    UIButton *aboutUsButton;
}

@property (nonatomic, retain) UIButton *settingsButton;
@property (nonatomic, retain) UIButton *infoButton;
@property (nonatomic, retain) UIButton *aboutUsButton;

-(void) addCustomElements;
-(void) selectTab:(int)tabID;

@end

RootViewController.m

-(void)viewDidLoad {

    UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"smallMenuBackground.png"]];    
    [mainTabBar insertSubview:imageView atIndex:0];
    [imageView release];

    [super viewDidLoad];
}

#import "CustomTabBarController.h"

@implementation CustomTabBarController

@synthesize settingsButton, infoButton, aboutUsButton;

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];


}
-(void)viewDidLoad
{
    [super viewDidLoad];
    [self addCustomElements];
}

-(void)addCustomElements
{
    // Background
    UIImageView* bgView = [[[UIImageView alloc] initWithImage:[UIImage imageNamed:@"tabBarBackground.png"]] autorelease];
    bgView.frame = CGRectMake(0, 420, 320, 60);
    [self.view addSubview:bgView];

    // Initialise our two images
    UIImage *btnImage = [UIImage imageNamed:@"settings.png"];
    UIImage *btnImageSelected = [UIImage imageNamed:@"settingsSelected.png"];

    self.settingsButton = [UIButton buttonWithType:UIButtonTypeCustom]; //Setup the button
    settingsButton.frame = CGRectMake(10, 426, 100, 54); // Set the frame (size and position) of the button)
    [settingsButton setBackgroundImage:btnImage forState:UIControlStateNormal]; // Set the image for the normal state of the button
    [settingsButton setBackgroundImage:btnImageSelected forState:UIControlStateHighlighted]; // Set the image for the selected state of the button
    [settingsButton setBackgroundImage:btnImageSelected forState:UIControlStateSelected]; // Set the image for the selected state of the button
    [settingsButton setBackgroundImage:btnImageSelected forState:UIControlStateDisabled];
    [settingsButton setImage:btnImageSelected forState:(UIControlStateHighlighted|UIControlStateSelected)];
    [settingsButton setTag:101]; // Assign the button a "tag" so when our "click" event is called we know which button was pressed.
    [settingsButton setSelected:true]; // Set this button as selected (we will select the others to false as we only want Tab 1 to be selected initially

    // Now we repeat the process for the other buttons
    btnImage = [UIImage imageNamed:@"info.png"];
    btnImageSelected = [UIImage imageNamed:@"infoSelected.png"];
    self.infoButton = [UIButton buttonWithType:UIButtonTypeCustom];
    infoButton.frame = CGRectMake(110, 426, 100, 54);
    [infoButton setBackgroundImage:btnImage forState:UIControlStateNormal];
    [infoButton setBackgroundImage:btnImageSelected forState:UIControlStateSelected];
    [infoButton setBackgroundImage:btnImageSelected forState:UIControlStateHighlighted];
    [infoButton setImage:btnImageSelected forState:(UIControlStateHighlighted|UIControlStateSelected)];

    [infoButton setTag:102];

    btnImage = [UIImage imageNamed:@"aboutUs.png"];
    btnImageSelected = [UIImage imageNamed:@"aboutUsSelected.png"];
    self.aboutUsButton = [UIButton buttonWithType:UIButtonTypeCustom];
    aboutUsButton.frame = CGRectMake(210, 426, 100, 54);
    [aboutUsButton setBackgroundImage:btnImage forState:UIControlStateNormal];
    [aboutUsButton setBackgroundImage:btnImageSelected forState:UIControlStateSelected];
    [aboutUsButton setBackgroundImage:btnImageSelected forState:UIControlStateHighlighted];
    [aboutUsButton setImage:btnImageSelected forState:(UIControlStateHighlighted|UIControlStateSelected)];

    [aboutUsButton setTag:103];

    // Add my new buttons to the view
    [self.view addSubview:settingsButton];
    [self.view addSubview:infoButton];
    [self.view addSubview:aboutUsButton];

    // Setup event handlers so that the buttonClicked method will respond to the touch up inside event.
    [settingsButton addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
    [infoButton addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
    [aboutUsButton addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
}

- (void)buttonClicked:(id)sender
{
    int tagNum = [sender tag];
    [self selectTab:tagNum];
}

- (void)selectTab:(int)tabID
{
    switch(tabID)
    {
        case 101:
            [settingsButton setSelected:true];
            [infoButton setSelected:false];
            [aboutUsButton setSelected:false];
            break;
        case 102:
            [settingsButton setSelected:false];
            [infoButton setSelected:true];
            [aboutUsButton setSelected:false];
            break;
        case 103:
            [settingsButton setSelected:false];
            [infoButton setSelected:false];
            [aboutUsButton setSelected:true];
            break;
    }   
    self.selectedIndex = tabID;
}

- (void)dealloc {
    [settingsButton release];
    [infoButton release];
    [aboutUsButton release];

    [super dealloc];
}

@end

这对我不起作用

更新

2012年1月23日更新

好的，我已经取得了一些进展。这只是在我升级到Xcode 4.2和IOS5之后才停止工作。我设法使用Interface Builder中的选项将其恢复，但现在它只适用于IOS5。理想情况下，我希望能够以编程的方式工作，但我现在会接受IB解决方案

我只是不能让它在以前的版本中工作

注意：我的选项卡栏仅在我的RootViewController上，它是我的应用程序的主屏幕

理想情况下，如果我能让Nithin建议的代码正常工作，那就太好了：

UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"tabBG.png"]];

if ([[[UIDevice currentDevice] systemVersion] floatValue] > 4.9) {
    //iOS 5
    [self.tabBarController.tabBar insertSubview:imageView atIndex:1];
}
else {
    //iOS 4.whatever and below
    [self.tabBarController.tabBar insertSubview:imageView atIndex:0];
}

[imageView release];

任何帮助都将不胜感激

问候,，

---

Stephen

获取自定义视图并将其添加到UITaB栏上。现在在该视图上添加按钮，并提供指向选项卡栏按钮的方法链接。现在你可以通过添加图像或任何东西在该视图上执行任何操作。它的工作原理类似于自定义选项卡栏。

您需要根据操作系统版本有条件地对其进行编码

如果您只支持iOS 5，只需使用选项卡栏的

backgroundImage

属性即可。如果你需要支持低于5的iOS版本，你应该添加一些条件代码来“破解”它。有几种方法可以做到这一点，这里有一种：

---

我过去所做的是创建自己的TabbarController来加载不同的

UIViewController

。使用此控制器，我可以操纵选项卡栏的外观以及其中的选项卡栏项。

我觉得这很好，但最初需要做一些工作。因为您必须“模拟”UITabBarController，因为您实际上没有使用“本机”UITabBar，所以您可以为UITabBarController使用自定义类并覆盖您的tabBarController。在那里，您可以设置所需的按钮和它们的图像操作

这就是自定义选项卡栏控制器类的外观：

//CustomTabBarController.h

IBOutlet UITabBar *mainTabBar;
    IBOutlet UITabBarItem *settingsBarItem;
    IBOutlet UITabBarItem *infoBarItem;
    IBOutlet UITabBarItem *aboutBarItem;

#import <UIKit/UIKit.h>

@interface CustomTabBarController : UITabBarController {
    UIButton *settingsButton;
    UIButton *infoButton;
    UIButton *aboutUsButton;
}

@property (nonatomic, retain) UIButton *settingsButton;
@property (nonatomic, retain) UIButton *infoButton;
@property (nonatomic, retain) UIButton *aboutUsButton;

-(void) addCustomElements;
-(void) selectTab:(int)tabID;

@end

---

希望这将对您有很大帮助。

就像之前在iOS 5上提到的那样，我建议您使用背景图像：

 jUst call these two methods
   hideTabBar;
   addCustomElements;

  hideTabBar method hides the original tabbar
  And addCustomElements method will add the custom tabbar image as well as custom tabbar button also 


- (void)hideTabBar
{
    for(UIView *view in self.tabBarController.view.subviews)
    {
        //      if([view isKindOfClass:[UITabBar class]])
        //      {
        //          view.hidden = YES;
        //          break;
        //      }

        if([view isKindOfClass:[UITabBar class]])
        {
            [view setFrame:CGRectMake(view.frame.origin.x, 480, view.frame.size.width, view.frame.size.height)];
        } 
        else 
        {
            [view setFrame:CGRectMake(view.frame.origin.x, view.frame.origin.y, view.frame.size.width, 480)];
        }


    }
}

-(void)addCustomElements
{
    // Initialise our two images
    UIImage *btnImage = [UIImage imageNamed:@"homet.png"];
    UIImage *btnImageSelected = [UIImage imageNamed:@"homehovert.png"];

    self.btn1 = [UIButton buttonWithType:UIButtonTypeCustom]; //Setup the button
    btn1.frame = CGRectMake(28, 446, 25,28); // Set the frame (size and position) of the button)
    [btn1 setBackgroundImage:btnImage forState:UIControlStateNormal]; // Set the image for the normal state of the button
    [btn1 setBackgroundImage:btnImageSelected forState:UIControlStateSelected]; // Set the image for the selected state of the button
    [btn1 setTag:0]; // Assign the button a "tag" so when our "click" event is called we know which button was pressed.
    [btn1 setSelected:true]; // Set this button as selected (we will select the others to false as we only want Tab 1 to be selected initially

    // Now we repeat the process for the other buttons
    btnImage = [UIImage imageNamed:@"blogt.png"];
    btnImageSelected = [UIImage imageNamed:@"bloghovert.png"];
    self.btn2 = [UIButton buttonWithType:UIButtonTypeCustom];
    btn2.frame = CGRectMake(107, 448, 22,28);
    [btn2 setBackgroundImage:btnImage forState:UIControlStateNormal];
    [btn2 setBackgroundImage:btnImageSelected forState:UIControlStateSelected];
    [btn2 setTag:1];

    btnImage = [UIImage imageNamed:@"networkt.png"];
    btnImageSelected = [UIImage imageNamed:@"networkhovert.png"];
    self.btn3 = [UIButton buttonWithType:UIButtonTypeCustom];
    btn3.frame = CGRectMake(180, 446, 35,29);
    [btn3 setBackgroundImage:btnImage forState:UIControlStateNormal];
    [btn3 setBackgroundImage:btnImageSelected forState:UIControlStateSelected];
    [btn3 setTag:2];

    btnImage = [UIImage imageNamed:@"contactt.png"];
    btnImageSelected = [UIImage imageNamed:@"contacthovert.png"];
    self.btn4 = [UIButton buttonWithType:UIButtonTypeCustom];
    btn4.frame = CGRectMake(262, 447, 32,28);
    [btn4 setBackgroundImage:btnImage forState:UIControlStateNormal];
    [btn4 setBackgroundImage:btnImageSelected forState:UIControlStateSelected];
    [btn4 setTag:3];

    self.img1 = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"tabbar.png"]] ;
    img1.frame = CGRectMake(0, 440, 320, 40); 




    [self.tabBarController.view addSubview:img1];
    // Add my new buttons to the view
    [self.tabBarController.view addSubview:btn1];
    [self.tabBarController.view addSubview:btn2];
    [self.tabBarController.view addSubview:btn3];
    [self.tabBarController.view addSubview:btn4];

    // Setup event handlers so that the buttonClicked method will respond to the touch up inside event.
    [btn1 addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
    [btn2 addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
    [btn3 addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
    [btn4 addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
}

UITabBar *tabBar = tabController.tabBar;
if ([tabBar respondsToSelector:@selector(setBackgroundImage:)]) {
    tabBar.backgroundImage = [UIImage imageNamed:@"TabBackground.png"];
}

始终使用类似于

respondsToSelector

的检查，而不是显式的版本检查。这将产生更安全、更具未来证明的代码

在iOS 4上，我建议您使用

-[uitabar drawRect:

方法，最好在子类中使用。然后在Interface Builder中，将

UITabBarController

s

UITabBar

自定义类（通常在MainWindow.xib中）设置为自定义子类

但是，如果您不使用MainWindow.xib，并且与在代码中生成

uitabarcontroller

的iOS 5代码模板一样，您只能使用

uitabar

上的类别覆盖

drawRect:

方法

// UITabBar+CustomBackground.h
@interface UITabBar (CustomBackground)
@end

// UITabBar+CustomBackground.m
@implementation UITabBar (CustomBackground)
- (void) drawRect:(CGRect)frame {
    [[UIColor redColor] set];

    CGContextRef ctx = UIGraphicsGetCurrentContext();
    CGContextFillRect(ctx, [self bounds]);
}
@end

---

这只适用于iOS 4.x及更早版本的系统，但这没关系，因为我们已经介绍了iOS 5。

您只需识别每个案例，使用Vinodh所说的

-respondToSelector检查版本。我建议您在UITabBar上创建一个类别，并轻松完成。因此，代码将具有以下形式：

    // UITabBar+Custom.h

    #import <UIKit/UIKit.h>
    #import <QuartzCore/QuartzCore.h>

    @interface UITabBar (Custom)
    -(void)setTabBarBackground:(UIImage *)backgroundImage;
    @end

//uitabar+Custom.h
#进口
#进口
@接口UITabBar（自定义）
-（void）setTabBarBackground:（UIImage*）backgroundImage；
@结束

和.m文件：

    // UITabBar+Custom.m

    #import "UITabBar+Custom.h"
    #import <objc/runtime.h>

    static char *backgroundImageKey;

    -(void)setImage:(UIImage *)anImage  {
          objc_setAssociatedObject(self, &backgroundImageKey, 
                anImage, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
          [self setNeedsDisplay];
    }

    -(UIImage *)image  {
          return objc_getAssociatedObject(self, &backgroundImageKey);
    }

    -(void)setTabBarBackground:(UIImage *)backgroundImage  {
         if([self respondsToSelector:@selector(setBackgroundImage:)]) {
              [self setBackgroundImage:backgroundImage];
         }  else  {
              [self setImage:backgroundImage];
         }
    }

    -(void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx  {
        UIGraphicsPushContext(ctx);
        UIImage *currentImage = [self image];
        CGContextTranslateCTM(ctx, 0, currentImage.size.height);
        CGContextScaleCTM(ctx, 1.0, -1.0);

        CGContextDrawImage(ctx, self.bounds, currentImage.CGImage);
        UIGraphicsPopContext();
    }

//uitabar+Custom.m
#导入“uitabar+Custom.h”
#进口
静态字符*背景图像键；
-（void）setImage:（UIImage*）动画{
objc_setAssociatedObject（self和backgroundImageKey，
动物（非原子的）；
[自我设置需要显示]；
}
-（UIImage*）图像{
返回objc_getAssociatedObject（self和backgroundImageKey）；
}
-（void）setTabBarBackground:（UIImage*）backgroundImage{
if（[self respondsToSelector:@selector（setBackgroundImage:）]））{
[自我挫折图像：背景图像]；
}否则{
[自我设置图像：背景图像]；
}
}
-（void）drawLayer:（CALayer*）层inContext:（CGContextRef）ctx{
UIGraphicsPushContext（ctx）；
UIImage*currentImage=[自映像]；
CGContextTranslateCTM（ctx，0，currentImage.size.height）；
CGContextScaleCTM（ctx，1.0，-1.0）；
CGContextDrawImage（ctx，self.bounds，currentImage.CGImage）；
UIGraphicsPopContext（）；
}

-drawLayer:inContext
将快速绘制背景图像。
正如我上面回答的，不需要添加UIView，就可以将背景图像添加到UIAbbar，当调用
[tabBar setNeedsDisplay]
时，图像可能会消失，因此我想到在
-drawLayer:layer inContext:ctx
中绘制图像（未调用
-drawInRect:rect
）。但是，如果可以避免调用
[tabBar setNeedsDisplay]
，则有一种简单的方法：

// UITabBar+Custom.m

#import "UITabBar+Custom.h"
#import <QuartzCore/QuartzCore.h>

-(void)setTabBarBackground:(UIImage *)backgroundImage  {
     if([self respondsToSelector:@selector(setBackgroundImage:)]) {
          // ios 5+
          [self setBackgroundImage:backgroundImage];
     }  else  {
          // ios 3.x / 4.x
          self.layer.contents = (id)backgroundImage.CGImage;
     }
}

//uitabar+Custom.m
#导入“uitabar+Custom.h”
#进口
-（void）setTabBarBackground:（UIImage*）backgroundImage{
if（[self respondsToSelector:@selector（setBackgroundImage:）]））{
//ios 5+
[自我挫折图像：背景图像]；
}否则{
//ios 3.x/4.x
self.layer.contents=（id）backgroundImage.CGImage；
}
}
摘自：

@Stephen检查此链接中给出的方法再次感谢Nithin，我尝试了链接中的示例，但无法使其正常工作。感谢Erfan，我只想在我的RootViewController中使用tabbar，如何调用自定义类？在这种情况下，您可以如上所述调用自定义类……只是有点不同，在y中添加UIViewController我们的故事板/主窗口。在应用程序委派类中，在ApplicationIDFinishLaunching内部，将viewController添加为窗口中的子视图。然后，您的RootViewController将显示在viewContr内部的屏幕中
// Change the tab bar background
 UIImage* tabBarBackground = [UIImage imageNamed:@"tabbar.png"];
 [[UITabBar appearance] setBackgroundImage:tabBarBackground];

// Change the tab bar background
UIImage *tabBarBackground = [UIImage imageNamed:@"CustomUITabbar.png"];
[[UITabBar appearance] setBackgroundImage:tabBarBackground];
[[UITabBar appearance] setTintColor:[UIColor whiteColor]];