Xcode 5和资产目录：如何引用LaunchImage？

Question

我正在使用Xcode 5的资产目录，并且我想用我的LaunchImage作为我的主页视图的背景图像（从“加载”到“加载”的过渡看起来非常平常）。

我想在资产目录中使用相同的条目来节省空间，而不必在两个不同的图像集中复制图像。

但是，调用：

UIImage *image = [UIImage imageNamed:@"LaunchImage"]; //returns nil 

Answer 1

的LaunchImages是特殊的，而实际上不是在设备上的资产类别。如果您使用iFunBox/iExplorer/etc（或者在模拟器或编译目录中），您可以看到最终名称，然后编写代码来使用它们 - 例如。对于仅iOS7的iPhone专用项目，这将设置正确的启动图像：

NSString *launchImage; 
if ((UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone) && 
    ([UIScreen mainScreen].bounds.size.height > 480.0f)) { 
    launchImage = @"LaunchImage-700-568h"; 
} else { 
    launchImage = @"LaunchImage-700"; 
} 

[self.launchImageView setImage:[UIImage imageNamed:launchImage]]; 

我把它放到viewDidLoad中。

这不是很理想，如果苹果会给我们一个很好的API来做到这一点，那将是非常好的。

Answer 2

这是LaunchImage的（几乎）完整列表（不包括没有状态栏iPad的图片）：

• LaunchImage-568h@2x.png
• LaunchImage-700-568h @ 2倍。 PNG
• LaunchImage-700-Landscape@2x~ipad.png
• LaunchImage-700 - 风景〜ipad.png
• LaunchImage-700-Portrait@2x~ipad.png
• LaunchImag E-700-肖像〜ipad.png
• LaunchImage-700@2x.png
• LaunchImage-Landscape@2x~ipad.png
• LaunchImage - 风景〜ipad.png
• LaunchImage画像@ 2倍〜 ipad.png
• LaunchImage画像〜ipad.png
• LaunchImage.png
• LaunchImage@2x.png
• LaunchImage-800-667h@2x.png（iPhone 6）
• LaunchImage-800-Portrait-736h@3x.png（iPhone 6加人像）
• LaunchImage-800-Landscape-736h@3x.png（iPhone 6加横向）
• LaunchImage-1100-肖像-2436h @ 3X巴纽（iPhone X人像）
• LaunchImage-1100-Landscape-2436h@3x.png（iPhone X风景）

Answer 3

继@ Pichirich的回答，我引用我的launchimage InterfaceBuilder下为：

“ LaunchImage.png“

...和Xcode 5.0.2，它会自动从资产目录中直接提取适当的图像。

这是我所期待 - 除了苹果的默默重命名“为Default.png”到“LaunchImage.png”恶毒肮脏举动:)

Answer 4

在documentation有明确规定：

“资产目录中的每个集合都有一个名称名称您可以使用该名称以编程方式加载集合中包含的任何单个图像要加载图像，请调用UIImage：ImageNamed：方法，传递名称包含图像的集合“。

使用Pichirichi的列表有助于解决这种不一致问题。

Answer 5

我刚刚写了一个通用的方法来获取iPhone和iPad的飞溅图像名称（横向，纵向），它为我工作，希望它也可以帮助你。我在其他SO答案的帮助下写了这篇文章，感谢@Pichirichi的整个列表。

+(NSString*)getLaunchImageName 
{ 

NSArray* images= @[@"LaunchImage.png", @"LaunchImage@2x.png",@"LaunchImage-700@2x.png",@"LaunchImage-568h@2x.png",@"LaunchImage-700-568h@2x.png",@"LaunchImage-700-Portrait@2x~ipad.png",@"LaunchImage-Portrait@2x~ipad.png",@"LaunchImage-700-Portrait~ipad.png",@"LaunchImage-Portrait~ipad.png",@"LaunchImage-Landscape@2x~ipad.png",@"LaunchImage-700-Landscape@2x~ipad.png",@"LaunchImage-Landscape~ipad.png",@"LaunchImage-700-Landscape~ipad.png"]; 

UIImage *splashImage; 

if ([self isDeviceiPhone]) 
{ 
    if ([self isDeviceiPhone4] && [self isDeviceRetina]) 
    { 
     splashImage = [UIImage imageNamed:images[1]]; 
     if (splashImage.size.width!=0) 
      return images[1]; 
     else 
      return images[2]; 
    } 
    else if ([self isDeviceiPhone5]) 
    { 
     splashImage = [UIImage imageNamed:images[1]]; 
     if (splashImage.size.width!=0) 
      return images[3]; 
     else 
      return images[4]; 
    } 
    else 
     return images[0]; //Non-retina iPhone 
} 
else if ([[UIDevice currentDevice] orientation]==UIDeviceOrientationPortrait || [[UIDevice currentDevice] orientation] == UIDeviceOrientationPortraitUpsideDown)//iPad Portrait 
{ 
    if ([self isDeviceRetina]) 
    { 
     splashImage = [UIImage imageNamed:images[5]]; 
     if (splashImage.size.width!=0) 
      return images[5]; 
     else 
      return images[6]; 
    } 
    else 
    { 
     splashImage = [UIImage imageNamed:images[7]]; 
     if (splashImage.size.width!=0) 
      return images[7]; 
     else 
      return images[8]; 
    } 

} 
else 
{ 
    if ([self isDeviceRetina]) 
    { 
     splashImage = [UIImage imageNamed:images[9]]; 
     if (splashImage.size.width!=0) 
      return images[9]; 
     else 
      return images[10]; 
    } 
    else 
    { 
     splashImage = [UIImage imageNamed:images[11]]; 
     if (splashImage.size.width!=0) 
      return images[11]; 
     else 
      return images[12]; 
    } 
} 
} 

其他实用的方法是

+(BOOL)isDeviceiPhone 
{ 
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone) 
{ 
    return TRUE; 
} 

return FALSE; 
} 

+(BOOL)isDeviceiPhone4 
{ 
if ([[UIScreen mainScreen] bounds].size.height==480) 
    return TRUE; 

return FALSE; 
} 


+(BOOL)isDeviceRetina 
{ 
if ([[UIScreen mainScreen] respondsToSelector:@selector(displayLinkWithTarget:selector:)] && 
    ([UIScreen mainScreen].scale == 2.0))  // Retina display 
{ 
    return TRUE; 
} 
else           // non-Retina display 
{ 
    return FALSE; 
} 
} 


+(BOOL)isDeviceiPhone5 
{ 
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone && [[UIScreen mainScreen] bounds].size.height>480) 
{ 
    return TRUE; 
} 
return FALSE; 
} 

Answer 6

我意识到，这不一定对每个人都是最好的解决方案，但最简单的（和最不容易出错的，恕我直言）的方式来做到这一点是通过使在Images.xcassets目录中单独输入。我称之为SplashImage。

当您添加新条目时，请确保不是以选择“新启动图像”作为选项。相反，请选择通用的“新建图像集”。接下来，打开检查员并选择相关选项。如果您正在为唯一视网膜显示设备上，因为我是，你可以选择以下内容：

这会使你的四个项目（iPhone 4S的，iPhone 5（S，C），iPhone 6 ，和iPhone 6 Plus）。是

相应的图像中的文件如下：

| Resolution (Xcode entry) | Launch Image name | Device   | 
|--------------------------|---------------------|------------------| 
| 1x      | Default-750.png  | iPhone 6   | 
| 2x      | Default@2x.png  | iPhone 4S  | 
| Retina 4 2x    | Default-568h@2x.png | iPhone 5, 5s, 5c | 
| 3x      | Default-1242.png | iPhone 6 Plus | 

当然，你已经这样做了之后，你可以简单地使用[UIImage imageNamed:@"SplashImage"]

Answer 7

我的应用程序目前只支持iOS版7和更高版本。

这是我从资产目录引用启动图像：

NSDictionary *dict = @{@"320x480" : @"LaunchImage-700", 
         @"320x568" : @"LaunchImage-700-568h", 
         @"375x667" : @"LaunchImage-800-667h", 
         @"414x736" : @"LaunchImage-800-Portrait-736h"}; 
NSString *key = [NSString stringWithFormat:@"%dx%d", 
    (int)[UIScreen mainScreen].bounds.size.width, 
    (int)[UIScreen mainScreen].bounds.size.height]; 
UIImage *launchImage = [UIImage imageNamed:dict[key]]; 

如果你想支持旧版本的IOS您可以添加更多的键值对。

Answer 8

可以通过一行代码轻松访问启动映像。

UIImage *myAppsLaunchImage = [UIImage launchImage]; 

请按照下面给出的步骤实现上述功能。

步骤1。通过创建类别&添加以下方法来扩展UIImage类。

+ (UIImage *)launchImage { 
    NSDictionary *dOfLaunchImage = [NSDictionary dictionaryWithObjectsAndKeys: 
            @"LaunchImage-568h@2x.png",@"568,320,2,8,p", // ios 8 - iphone 5 - portrait 
            @"LaunchImage-568h@2x.png",@"568,320,2,8,l", // ios 8 - iphone 5 - landscape 
            @"LaunchImage-700-568h@2x.png",@"568,320,2,7,p", // ios 7 - iphone 5 - portrait 
            @"LaunchImage-700-568h@2x.png",@"568,320,2,7,l", // ios 7 - iphone 5 - landscape 
            @"LaunchImage-700-Landscape@2x~ipad.png",@"1024,768,2,7,l", // ios 7 - ipad retina - landscape 
            @"LaunchImage-700-Landscape~ipad.png",@"1024,768,1,7,l", // ios 7 - ipad regular - landscape 
            @"LaunchImage-700-Portrait@2x~ipad.png",@"1024,768,2,7,p", // ios 7 - ipad retina - portrait 
            @"LaunchImage-700-Portrait~ipad.png",@"1024,768,1,7,p", // ios 7 - ipad regular - portrait 
            @"LaunchImage-700@2x.png",@"480,320,2,7,p", // ios 7 - iphone 4/4s retina - portrait 
            @"LaunchImage-700@2x.png",@"480,320,2,7,l", // ios 7 - iphone 4/4s retina - landscape 
            @"LaunchImage-Landscape@2x~ipad.png",@"1024,768,2,8,l", // ios 8 - ipad retina - landscape 
            @"LaunchImage-Landscape~ipad.png",@"1024,768,1,8,l", // ios 8 - ipad regular - landscape 
            @"LaunchImage-Portrait@2x~ipad.png",@"1024,768,2,8,p", // ios 8 - ipad retina - portrait 
            @"LaunchImage-Portrait~ipad.png",@"1024,768,1,8,l", // ios 8 - ipad regular - portrait 
            @"LaunchImage.png",@"480,320,1,7,p", // ios 6 - iphone 3g/3gs - portrait 
            @"LaunchImage.png",@"480,320,1,7,l", // ios 6 - iphone 3g/3gs - landscape 
            @"LaunchImage@2x.png",@"480,320,2,8,p", // ios 6,7,8 - iphone 4/4s - portrait 
            @"LaunchImage@2x.png",@"480,320,2,8,l", // ios 6,7,8 - iphone 4/4s - landscape 
            @"LaunchImage-800-667h@2x.png",@"667,375,2,8,p", // ios 8 - iphone 6 - portrait 
            @"LaunchImage-800-667h@2x.png",@"667,375,2,8,l", // ios 8 - iphone 6 - landscape 
            @"LaunchImage-800-Portrait-736h@3x.png",@"736,414,3,8,p", // ios 8 - iphone 6 plus - portrait 
            @"LaunchImage-800-Landscape-736h@3x.png",@"736,414,3,8,l", // ios 8 - iphone 6 plus - landscape 
            nil]; 
    NSInteger width = ([UIScreen mainScreen].bounds.size.width>[UIScreen mainScreen].bounds.size.height)?[UIScreen mainScreen].bounds.size.width:[UIScreen mainScreen].bounds.size.height; 
    NSInteger height = ([UIScreen mainScreen].bounds.size.width>[UIScreen mainScreen].bounds.size.height)?[UIScreen mainScreen].bounds.size.height:[UIScreen mainScreen].bounds.size.width; 
    NSInteger os = [[[[[UIDevice currentDevice] systemVersion] componentsSeparatedByString:@"."] objectAtIndex:0] integerValue]; 
    NSString *strOrientation = UIDeviceOrientationIsLandscape([[UIDevice currentDevice] orientation])?@"l":@"p"; 
    NSString *strImageName = [NSString stringWithFormat:@"%li,%li,%li,%li,%@",width,height,(NSInteger)[UIScreen mainScreen].scale,os,strOrientation]; 
    UIImage *imageToReturn = [UIImage imageNamed:[dOfLaunchImage valueForKey:strImageName]]; 
    if([strOrientation isEqualToString:@"l"] && [strImageName rangeOfString:@"Landscape"].length==0) { 
     imageToReturn = [UIImage rotate:imageToReturn orientation:UIImageOrientationRight]; 
    } 
    return imageToReturn; 
} 

第2步：以上方法应该加入以下代码也成UIImage

static inline double radians (double degrees) {return degrees * M_PI/180;} 

+ (UIImage *)rotate:(UIImage*)src orientation:(UIImageOrientation) orientation { 
    UIGraphicsBeginImageContext(src.size); 
    CGContextRef context = UIGraphicsGetCurrentContext(); 
    if (orientation == UIImageOrientationRight) { 
     CGContextRotateCTM (context, radians(90)); 
    } else if (orientation == UIImageOrientationLeft) { 
     CGContextRotateCTM (context, radians(-90)); 
    } else if (orientation == UIImageOrientationDown) { 
     // NOTHING 
    } else if (orientation == UIImageOrientationUp) { 
     CGContextRotateCTM (context, radians(90)); 
    } 
    [src drawAtPoint:CGPointMake(0, 0)]; 
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); 
    UIGraphicsEndImageContext(); 
    return image; 
} 

Answer 9

随着Pichirichi的答案，我已经实现了以下类别的帮助同一类别来工作（iOS版7+）： UIImage+AssetLaunchImage

它实际上只是在fl上生成名称Ÿ，但可能会有所帮助。

Answer 10

- (NSString *)splashImageNameForOrientation:(UIInterfaceOrientation)orientation { 
    CGSize viewSize = self.view.bounds.size; 
    NSString* viewOrientation = @"Portrait"; 
    if (UIDeviceOrientationIsLandscape(orientation)) { 
     viewSize = CGSizeMake(viewSize.height, viewSize.width); 
     viewOrientation = @"Landscape"; 
    } 

    NSArray* imagesDict = [[[NSBundle mainBundle] infoDictionary] valueForKey:@"UILaunchImages"]; 
    for (NSDictionary* dict in imagesDict) { 
     CGSize imageSize = CGSizeFromString(dict[@"UILaunchImageSize"]); 
     if (CGSizeEqualToSize(imageSize, viewSize) && [viewOrientation isEqualToString:dict[@"UILaunchImageOrientation"]]) 
      return dict[@"UILaunchImageName"]; 
    } 
    return nil; 
} 

Answer 11

这里是基于上述Cherpak Evgeny提供的解决方案的UIImage类。

的UIImage + SplashImage.h：

#import <UIKit/UIKit.h> 

/** 
* Category on `UIImage` to access the splash image. 
**/ 
@interface UIImage (SplashImage) 

/** 
* Return the name of the splash image for a given orientation. 
* @param orientation The interface orientation. 
* @return The name of the splash image. 
**/ 
+ (NSString *)si_splashImageNameForOrientation:(UIInterfaceOrientation)orientation; 

/** 
* Returns the splash image for a given orientation. 
* @param orientation The interface orientation. 
* @return The splash image. 
**/ 
+ (UIImage*)si_splashImageForOrientation:(UIInterfaceOrientation)orientation; 

@end 

的UIImage + SplashImage.m：

#import "UIImage+SplashImage.h" 

@implementation UIImage (SplashImage) 

+ (NSString *)si_splashImageNameForOrientation:(UIInterfaceOrientation)orientation 
{ 
    CGSize viewSize = [UIScreen mainScreen].bounds.size; 

    NSString *viewOrientation = @"Portrait"; 

    if (UIDeviceOrientationIsLandscape(orientation)) 
    { 
     viewSize = CGSizeMake(viewSize.height, viewSize.width); 
     viewOrientation = @"Landscape"; 
    } 

    NSArray* imagesDict = [[[NSBundle mainBundle] infoDictionary] valueForKey:@"UILaunchImages"]; 

    for (NSDictionary *dict in imagesDict) 
    { 
     CGSize imageSize = CGSizeFromString(dict[@"UILaunchImageSize"]); 
     if (CGSizeEqualToSize(imageSize, viewSize) && [viewOrientation isEqualToString:dict[@"UILaunchImageOrientation"]]) 
      return dict[@"UILaunchImageName"]; 
    } 
    return nil; 
} 

+ (UIImage*)si_splashImageForOrientation:(UIInterfaceOrientation)orientation 
{ 
    NSString *imageName = [self si_splashImageNameForOrientation:orientation]; 
    UIImage *image = [UIImage imageNamed:imageName]; 
    return image; 
} 

@end 

Answer 12

Cherpak叶夫根的答案的斯威夫特版本：

func splashImageForOrientation(orientation: UIInterfaceOrientation) -> String { 
     var viewSize = self.view.bounds.size 
     var viewOrientation = "Portrait" 
     if UIInterfaceOrientationIsLandscape(orientation) { 
      viewSize = CGSizeMake(viewSize.height, viewSize.width) 
      viewOrientation = "Landscape" 
     } 
     let imagesDict = NSBundle.mainBundle().infoDictionary as Dictionary<NSObject,AnyObject>! 
     let imagesArray = imagesDict["UILaunchImages"] as NSArray 
     for dict in imagesArray { 
      let dictNSDict = dict as NSDictionary 
      let imageSize = CGSizeFromString(dictNSDict["UILaunchImageSize"] as String) 
      if CGSizeEqualToSize(imageSize, viewSize) && viewOrientation == (dictNSDict["UILaunchImageOrientation"] as String) { 
       return dictNSDict["UILaunchImageName"] as String 
      } 
     } 
     return "" 
    } 

Answer 13

@ codeman的答案更新f或雨燕1.2：

func splashImageForOrientation(orientation: UIInterfaceOrientation, size: CGSize) -> String? { 
    var viewSize  = size 
    var viewOrientation = "Portrait" 

    if UIInterfaceOrientationIsLandscape(orientation) { 
     viewSize  = CGSizeMake(size.height, size.width) 
     viewOrientation = "Landscape" 
    } 

    if let imagesDict = NSBundle.mainBundle().infoDictionary as? [String: AnyObject] { 
     if let imagesArray = imagesDict["UILaunchImages"] as? [[String: String]] { 
      for dict in imagesArray { 
       if let sizeString = dict["UILaunchImageSize"], let imageOrientation = dict["UILaunchImageOrientation"] { 
        let imageSize = CGSizeFromString(sizeString) 
        if CGSizeEqualToSize(imageSize, viewSize) && viewOrientation == imageOrientation { 
         if let imageName = dict["UILaunchImageName"] { 
          return imageName 
         } 
        } 
       } 
      } 
     } 
    } 

    return nil 

} 

调用它，并支持旋转为iOS 8：

override func viewWillAppear(animated: Bool) { 
    if let img = splashImageForOrientation(UIApplication.sharedApplication().statusBarOrientation, size: self.view.bounds.size) { 
     backgroundImage.image = UIImage(named: img) 
    } 
} 

override func viewWillTransitionToSize(size: CGSize, withTransitionCoordinator coordinator: UIViewControllerTransitionCoordinator) { 
    let orientation = size.height > size.width ? UIInterfaceOrientation.Portrait : UIInterfaceOrientation.LandscapeLeft 

    if let img = splashImageForOrientation(orientation, size: size) { 
     backgroundImage.image = UIImage(named: img) 
    } 

} 

这正是我需要的，谢谢！