在iOS设备和iOS模拟器上测试时，有一个小问题。看起来模拟器(XCode 6.0.1)在[[UIScreen mainScreen] bounds]中给出了宽度和高度的切换值。大小，取决于设备方向。

因此，在确定正确的物理屏幕尺寸时，这可能是一个问题。此代码还有助于区分所有2014年。iPhone型号:

iPhone4s iPhone5(和iPhone5s) iPhone6(及iPhone6+)

它也可以很容易地改变，使区别，如iPhone6从iPhone6+。

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    CGSize iOSDeviceScreenSize = [[UIScreen mainScreen] bounds].size;

    if ([UIDevice currentDevice].userInterfaceIdiom == UIUserInterfaceIdiomPhone)
    {
        if (iOSDeviceScreenSize.width > 568 || // for iOS devices
            iOSDeviceScreenSize.height > 568) // for iOS simulator
        {   // iPhone 6 and iPhone 6+

            // Instantiate a new storyboard object using the storyboard file named Storyboard_iPhone6
            storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard_iPhone6" bundle:nil];

            NSLog(@"loaded iPhone6 Storyboard");
        }
        else if (iOSDeviceScreenSize.width == 568 || // for iOS devices
                 iOSDeviceScreenSize.height == 568) // for iOS simulator
        {   // iPhone 5 and iPod Touch 5th generation: 4 inch screen (diagonally measured)

            // Instantiate a new storyboard object using the storyboard file named Storyboard_iPhone5
            storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard_iPhone5" bundle:nil];

            NSLog(@"loaded iPhone5 Storyboard");
        }
        else
        {   // iPhone 3GS, 4, and 4S and iPod Touch 3rd and 4th generation: 3.5 inch screen (diagonally measured)

                // Instantiate a new storyboard object using the storyboard file named Storyboard_iPhone4
            storyboard = [UIStoryboard story    boardWithName:@"MainStoryboard_iPhone" bundle:nil];

                NSLog(@"loaded iPhone4 Storyboard");
        }
    }
    else if ([UIDevice currentDevice].userInterfaceIdiom == UIUserInterfaceIdiomPad)
    {   // The iOS device = iPad

        storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard_iPadnew" bundle:nil];

        NSLog(@"loaded iPad Storyboard");
    }

    // rest my code
}

I never faced such an issue with any device as I've had one codebase for all, without any hardcoded values. What I do is to have the maximum sized image as resource instead of one for each device. For example, I would have one for retina display and show it as aspect fit so it will be views as is on every device. Coming to deciding the frame of button, for instance, at run time. For this I use the % value of the patent view, example , if I want the width to be half of parent view take 50 % of parent and same applies for height and center.

有了这个，我甚至不需要xib。

在单例类中尝试下面的方法:

-(NSString *)typeOfDevice
    {
        if(UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone)
        {
            CGSize result = [[UIScreen mainScreen] bounds].size;
            if(result.height == 480)
            {
                return @"Iphone";
            }
            if(result.height == 568)
            {
                return @"Iphone 5";
            }
        }
        else{
            return @"Ipad";;
        }


        return @"Iphone";
    }

Download and install latest version of Xcode. Set a Launch Screen File for your app (in the general tab of your target settings). This is how you get to use the full size of any screen, including iPad split view sizes in iOS 9. Test your app, and hopefully do nothing else, since everything should work magically if you had set auto resizing masks properly, or used Auto Layout. If you didn't, adjust your view layouts, preferably with Auto Layout. If there is something you have to do for the larger screens specifically, then it looks like you have to check height of [[UIScreen mainScreen] bounds] as there seems to be no specific API for that. As of iOS 8 there are also size classes that abstract screen sizes into regular or compact vertically and horizontally and are recommended way to adapt your UI.

我想，它不是在所有情况下都能工作，但在我的特定项目中，它避免了我对nib文件的重复:

在common.h中，你可以根据屏幕高度来做这些定义:

#define HEIGHT_IPHONE_5 568
#define IS_IPHONE   ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone)
#define IS_IPHONE_5 ([[UIScreen mainScreen] bounds ].size.height == HEIGHT_IPHONE_5)

在你的基本控制器中:

- (void)viewDidLoad
{
    [super viewDidLoad];
    if (IS_IPHONE_5) {
        CGRect r = self.view.frame;
        r.size.height = HEIGHT_IPHONE_5 - 20;
        self.view.frame = r;
    }
    // now the view is stretched properly and not pushed to the bottom
    // it is pushed to the top instead...

    // other code goes here...
}

According to me the best way of dealing with such problems and avoiding couple of condition required for checking the the height of device, is using the relative frame for views or any UI element which you are adding to you view for example: if you are adding some UI element which you want should at the bottom of view or just above tab bar then you should take the y origin with respect to your view's height or with respect to tab bar (if present) and we have auto resizing property as well. I hope this will work for you