How does one get UI_USER_INTERFACE_IDIOM() to work with iPhone OS SDK < 3.2

Question

Apple advises using the following code to detect whether running on an iPad or iPhone/iPod Touch:

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
  // The device is an iPad running iPhone 3.2 or later.
  // [for example, load appropriate iPad nib file]
}
else {
  // The device is an iPhone or iPod touch.
  // [for example, load appropriate iPhone nib file]
}

The problem is that UI_USER_INTERFACE_IDIOM() and UIUserInterfaceIdiomPad are NOT defined in the SDKs prior to 3.2. This seems to completely defeat the purpose of such a function. They can only be compiled and run on iPhone OS 3.2 (iPhone OS 3.2 can only be run on iPad). So if you can use UI_USER_INTERFACE_IDIOM(), the result will always be to indicate an iPad.

If you include this code and target OS 3.1.3 (the most recent iPhone/iPod Touch OS) in order to test your iPhone-bound universal app code, you will get compiler errors since the symbols are not defined in 3.1.3 or earlier, when compiling for iPhone simulator 3.1.3.

If this is the recommended-by-Apple approach to runtime device-detection, what am I doing wrong? Has anyone succeeded using this approach to device-detection?

Answer 1

I do this to get the code to compile in both 3.1.3 and 3.2:

BOOL iPad = NO;
#ifdef UI_USER_INTERFACE_IDIOM
iPad = (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad);
#endif
if (iPad) {
// iPad specific code here
} else {
// iPhone/iPod specific code here
}

I also wrote a quick blog post about it here: http://www.programbles.com/2010/04/03/compiling-conditional-code-in-universal-iphone-ipad-applications/

Answer 2

This is what I use:

- (BOOL) amIAnIPad {
    #if (__IPHONE_OS_VERSION_MAX_ALLOWED >= 30200)
        if ([[UIDevice currentDevice] respondsToSelector: @selector(userInterfaceIdiom)])
            return ([UIDevice currentDevice].userInterfaceIdiom == UIUserInterfaceIdiomPad);
    #endif
    return NO;
}

This conditionally compiles, so you can still build for the 3.0 sim. It then checks to see if the UIDevice class responds to the selector. If either of these fail, it's not an iPad.

Answer 3

GitHub-issues 서비스에서 답변을 받았습니다.그 이유는 httpd 사용자 가이 기능을 호출 할 수 없다는 것이 었습니다. 여기서는 $ PATH 경로 환경을 확장하는 샘플입니다.myconfig.conf.php 파일에 이것을 추가했습니다.

'environment.append-paths' => array('/usr/local/bin'),

.

경로에 대한 비경화로 경로를 추가하는 것이 좋습니다.

Answer 4

I believe the answer is simply do not attempt to run the code on iPhone simulator 3.1.3 or earlier. Always compile with a 3.2 SDK. The iPhone simulator 3.2 will get you the iPad simulator, or compile for iPhone Device 3.2 and put the app on a phone to test it.

There is no way to compile against 3.2 SDK and use a 3.1.3 or earlier simulator.

Answer 5

Instead of any compiler based stuff I use:

- (BOOL)deviceIsAnIPad {
if ([[UIDevice currentDevice] respondsToSelector:@selector(userInterfaceIdiom)])
    //We can test if it's an iPad. Running iOS3.2+
    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad)
        return YES; //is an iPad
    else 
        return NO; //is an iPhone
else 
    return NO; //does not respond to selector, therefore must be < iOS3.2, therefore is an iPhone
}

Answer 6

나는 당신이 이것을 원한다고 생각할 것입니다 :

$('#rows').on('mouseenter', "div.row div:nth-child(1), div.row div:nth-child(2)", this , function() {
    $('img', this).stop().animate({"bottom":"0px"}, "fast");

    // when placed inside, the value of this makes more sense?
    $('div', this).off("mouseleave").on("mouseleave", function() {
        $('img',this).stop().animate({"bottom":"94px"}, "fast");    
    }); 
});

.

쓴이 문에서 this의 값은 window가 아마도 $('div', this)가 페이지의 모든 div를 대상으로합니다.

$('div', this).off("mouseleave").on("mouseleave", function() {
    $('img',this).stop().animate({"bottom":"94px"}, "fast");    
}); 

.

Answer 7

This seems to completely defeat the purpose of such a function. They can only be compiled and run on iPhone OS 3.2 (iPhone OS 3.2 can only be run on iPad). So if you can use UI_USER_INTERFACE_IDIOM(), the result will always be to indicate an iPad.

This is completely incorrect. It can be compiled on Base SDK of 3.2, but it can be run on any OS, if you set the deployment target appropriately.

Answer 8

UI_USER_INTERFACE_IDIOM() and UIUserInterfaceIdiomPad can be used on iOS3.2 and upwards, the important part being the 'upwards'. Sure. iOS3.2 is only for iPad, but iOS4.0 and beyond run on both iPhones and iPads, so the check isn't as pointless as you think.