iOS SDK是否提供了一种简单的方法来检查currentDevice是否具有高分辨率的显示器(retina) ?

我现在发现的最好的方法是:

    if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)] == YES && [[UIScreen mainScreen] scale] == 2.00) {
         // RETINA DISPLAY
    }

当前回答

primulaveris's的修改版本,以简化最常见的用例。我用的是swift 2.2,但这应该没有关系。

extension UIScreen {
    static var isRetina: Bool {
        return screenScale >= 2.0
    }

    static var isRetinaHD: Bool {
        return screenScale >= 3.0
    }

    static var screenScale:CGFloat {
        return UIScreen.mainScreen().scale
    }
}

然后像这样简单地使用它们

print(UIScreen.isRetina)
print(UIScreen.isRetinaHD)
print(UIScreen.screenScale)

其他回答

@sickp的答案是正确的。为了简化操作,将这一行添加到共享中。pch文件:

#define IS_RETINA ([[UIScreen mainScreen] respondsToSelector:@selector(displayLinkWithTarget:selector:)] && ([UIScreen mainScreen].scale >= 2.0))

然后在任何文件中你都可以这样做:

if(IS_RETINA)
{
   // etc..
}
// .h
UIKIT_EXTERN bool isRetinaDisplay();

// .m
bool isRetinaDisplay()
{
    static bool flag;
#ifdef __BLOCKS__
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        if([[UIScreen mainScreen] respondsToSelector:@selector(scale)])
        {
            flag = [[UIScreen mainScreen] scale] > 1.0;
        }
        else
        {
            flag = false;
        }
    });
#else
    static bool onceToken;
    if(onceToken == false)
    {
        onceToken = true;
        if([[UIScreen mainScreen] respondsToSelector:@selector(scale)])
        {
            flag = [[UIScreen mainScreen] scale] > 1.0;
        }
        else
        {
            flag = false;
        }
    }
#endif
    return flag;
}

试试这个

if ([[UIScreen mainScreen] respondsToSelector:@selector(displayLinkWithTarget:selector:)] &&
    ([UIScreen mainScreen].scale == 2.0))
{
    // Retina display
    NSLog(@"---------------Retina display");
} else {
    // non-Retina display
    NSLog(@"---------------non-Retina display");
}

比较浮点值是否相等总是让人感觉有点不可靠。 两者我都喜欢

[UIScreen mainScreen].scale > 1.0;

or

[UIScreen mainScreen].scale < 2.0;
+(BOOL)iPhoneRetina{
    return ([[UIScreen mainScreen] respondsToSelector:@selector(displayLinkWithTarget:selector:)] && ([UIScreen mainScreen].scale == 2.0))?1:0;
}