如何在Objective-C中更改标签栏的背景图像？

I am develop in objective-C. I want to change the tab bar background like the following picture:

我是在Objective-C中发展的。我想更改标签栏背景，如下图所示：

And the code is like the following:

代码如下：

UIImage *tabBarBackground = [UIImage imageNamed:@"tabbaritem_background.png"];
[[UITabBar appearance] setBackgroundImage:tabBarBackground];

But after setting the background image , the background is not at the correct place like the following:

但是在设置背景图像后，背景不在正确的位置，如下所示：

The background image should be place at the bottom like the background in above picture.

背景图像应该像上图中的背景一样放在底部。

Did I missing something ? Can someone help me ?

我错过了什么吗？有人能帮我吗 ？

Thanks in advance.

提前致谢。

4 个解决方案

#1

I think is somewhere you go wrong, check if is this steps:

我认为是你出错的地方，检查这是否是这个步骤：

1. In the storyboard change the ViewController's background color for test.
2. 在故事板中更改ViewController的背景颜色以进行测试。

2. Embed the ViewController in Tab Bar Controller
3. 在窗口栏控制器中嵌入ViewController

3. In the ViewController.m you can set the tabbar bacground color:

   在ViewController.m中，您可以设置tabbar bacground颜色：

   - (void)viewDidLoad {
       [super viewDidLoad];
       // Do any additional setup after loading the view, typically from a nib.
   
       [[UITabBar appearance] setBackgroundColor:[UIColor grayColor]]; // Here you can set the converted color form image, make sure the imageSize fit.
   }
   

4. The result is below:

   结果如下：

#2

I think the method - (UIImage *)resizableImageWithCapInsets:(UIEdgeInsets)capInsets resizingMode:(UIImageResizingMode)resizingMode you can try, because your backgroudimage's size is not equal to tabbar'size.

我认为方法 - （UIImage *）resizableImageWithCapInsets：（UIEdgeInsets）capInsets resizingMode：（UIImageResizingMode）resizingMode你可以尝试，因为你的backgroudimage的大小不等于tabbar'size。

#3

Try this method to change your image to a ScaleImage.

尝试使用此方法将图像更改为ScaleImage。

+(UIImage *)getScaleImageNamed:(NSString *)name{
    UIImage *nomalImage = [UIImage imageNamed:name];

    CGFloat hInset = floorf(nomalImage.size.width / 2);
    CGFloat vInset = floorf(nomalImage.size.height / 2);

    UIImage *res = [nomalImage resizableImageWithCapInsets:UIEdgeInsetsMake(vInset, hInset, vInset, hInset)];

    return res;
}

#4

Steps you may miss, hope that can help.

您可能会错过的步骤，希望可以提供帮助。

1. Make sure you have imported the background image (e.g. in Assets.xcassets)
2. 确保已导入背景图像（例如，在Assets.xcassets中）
3. Use resizableImageWithCapInsets: to resize the background image
4. 使用resizableImageWithCapInsets：调整背景图像的大小

5. Put the UIAppearance settings in AppDelegate.m:

   将UIAppearance设置放在AppDelegate.m中：

   [[UITabBar appearance] setBackgroundImage:[[UIImage imageNamed:@"tabbaritem_background.png"] resizableImageWithCapInsets:UIEdgeInsetsMake(0, 0, 0, 0)]];