ios Xcode 5 和资产目录：如何引用 LaunchImage？

Xcode 5 & Asset Catalog: How to reference the LaunchImage?

提问by toblerpwn

I am using Xcode 5's Asset Catalog, and I would like to use my LaunchImageas the background image of my home view (a pretty common practice to make the transition from 'loading' to 'loaded' look smooth).

我正在使用 Xcode 5 的资产目录，我想使用我的LaunchImage作为我的主视图的背景图像（一种非常常见的做法，使从“加载”到“加载”的过渡看起来很平滑）。

I would like to use the same entry in the Asset Catalog to save space and not have to replicate the image in two different Image Sets.

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。

However, calling:

但是，调用：

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

回答by Pichirichi

This is the (almost) complete list of the LaunchImage (excluding the iPad images with no status bar):

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

• [email protected]
• [email protected]
• LaunchImage-700-Landscape@2x~ipad.png
• LaunchImage-700-Landscape~ipad.png
• LaunchImage-700-Portrait@2x~ipad.png
• LaunchImage-700-Portrait~ipad.png
• [email protected]
• LaunchImage-Landscape@2x~ipad.png
• LaunchImage-Landscape~ipad.png
• LaunchImage-Portrait@2x~ipad.png
• LaunchImage-Portrait~ipad.png
• LaunchImage.png
• [email protected]
• [email protected] (iPhone 6)
• [email protected] (iPhone 6 Plus Portrait)
• [email protected] (iPhone 6 Plus Landscape)
• [email protected] (iPhone X Portrait)
• [email protected] (iPhone X Landscape)

• [email protected]
• [email protected]
• LaunchImage-700-Landscape@2x~ipad.png
• LaunchImage-700-Landscape~ipad.png
• LaunchImage-700-Portrait@2x~ipad.png
• LaunchImage-700-Portrait~ipad.png
• [email protected]
• LaunchImage-Landscape@2x~ipad.png
• LaunchImage-Landscape~ipad.png
• LaunchImage-Portrait@2x~ipad.png
• LaunchImage-Portrait~ipad.png
• 启动图片.png
• [email protected]
• [email protected] (iPhone 6)
• [email protected] (iPhone 6 Plus 人像)
• [email protected] (iPhone 6 Plus Landscape)
• [email protected]（iPhone X 人像）
• [email protected] (iPhone X Landscape)

回答by Cherpak Evgeny

- (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;
}

回答by JosephH

The LaunchImages are special, and aren't actually an asset catalog on the device. If you look using iFunBox/iExplorer/etc (or on the simulator, or in the build directory) you can see the final names, and then write code to use them - eg. for an iOS7-only iPhone-only project, this will set the right launch image:

LaunchImages 很特别，实际上并不是设备上的资产目录。如果您查看使用 iFunBox/iExplorer/etc（或在模拟器上，或在构建目录中），您可以看到最终名称，然后编写代码来使用它们 - 例如。对于仅限 iOS7 的仅限 iPhone 的项目，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]];

I put this into viewDidLoad.

我把它放到 viewDidLoad 中。

This isn't really ideal, it would be great if Apple would give us a nice API to do this.

这不是很理想，如果 Apple 能给我们一个很好的 API 来做到这一点，那就太好了。

回答by nonamelive

My app currently only supports iOS 7 and later.

我的应用目前仅支持 iOS 7 及更高版本。

This is how I reference the launch image from the asset catalog:

这是我从资产目录中引用启动图像的方式：

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]];

You can add more key value pairs if you want to support older iOS versions.

如果您想支持较旧的 iOS 版本，您可以添加更多键值对。

回答by vilanovi

Here a category on UIImage based on the solution provided by Cherpak Evgeny above.

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

UIImage+SplashImage.h:

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

UIImage+SplashImage.m:

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

回答by Anthony Scott

@codeman's answer updated for Swift 1.2:

@codeman 为 Swift 1.2 更新了答案：

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

}

To call it, and to support rotation for iOS 8:

调用它，并支持 iOS 8 的旋转：

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)
    }

}

Just what I needed, thanks!

正是我需要的，谢谢！

回答by codeman

Swift version of Cherpak Evgeny's answer:

Cherpak Evgeny 答案的 Swift 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 ""
    }

回答by zaheer

I just wrote a general method to get the splash image name for iPhone and iPad (Landscape, Portrait), It worked for me, Hope It helps you as well. I wrote this with help of other SO answers, thanks @Pichirichi for whole list.

我刚刚写了一个通用方法来获取 iPhone 和 iPad（横向、纵向）的初始图像名称，它对我有用，希望它也能帮助你。我在其他 SO 答案的帮助下写了这篇文章，感谢 @Pichirichi 提供整个列表。

+(NSString*)getLaunchImageName
{

 NSArray* images= @[@"LaunchImage.png", @"[email protected]",@"[email protected]",@"[email protected]",@"[email protected]",@"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];
    }
 }
}

Other utility methods are

其他实用方法是

+(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;
}

回答by Adam

Following @Pichirich's answer, I referenced my launchimage in InterfaceBuilder as:

按照@Pichirich 的回答，我在 InterfaceBuilder 中引用了我的启动图像：

"LaunchImage.png"

“启动图像.png”

...and with Xcode 5.0.2, it's automatically plucking the appropriate image straight out of the Asset Catalog.

...使用 Xcode 5.0.2，它会自动直接从资产目录中提取适当的图像。

This is what I'd expect - except for Apple's viciously nasty move of silently renaming "Default.png" to "LaunchImage.png" :)

这就是我所期望的 - 除了 Apple 将“Default.png”默默地重命名为“LaunchImage.png”的恶毒举动：）

回答by Vladimír Slavík

In the documentationthere is clearly stated:

在文档中有明确的说明：

"Each set in an asset catalog has a name. You can use that nameto programmatically load any individual image contained in the set. To load an image, call the UIImage:ImageNamed:method, passing the name of the set that contains the image."

“资产目录中的每个集合都有一个名称。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，传递包含图像的集合的名称.”

Using Pichirichi's list helps to solve this inconsistency.

使用 Pichirichi 的列表有助于解决这种不一致。