什么是等价的UI_USER_INTERFACE_IDIOM()在Swift检测之间的iPhone和iPad?
我得到一个使用未解决的标识符错误时,在Swift编译。
什么是等价的UI_USER_INTERFACE_IDIOM()在Swift检测之间的iPhone和iPad?
我得到一个使用未解决的标识符错误时,在Swift编译。
当前回答
如果你想检查当前设备是iPad还是iPhone,那么你可以使用这些代码行:
if(UIDevice.currentDevice().userInterfaceIdiom == .Pad){
}else if(UIDevice.currentDevice().userInterfaceIdiom == .Phone){
}
其他回答
Swift 4.2 - 5.1扩展
public extension UIDevice {
class var isPhone: Bool {
return UIDevice.current.userInterfaceIdiom == .phone
}
class var isPad: Bool {
return UIDevice.current.userInterfaceIdiom == .pad
}
class var isTV: Bool {
return UIDevice.current.userInterfaceIdiom == .tv
}
class var isCarPlay: Bool {
return UIDevice.current.userInterfaceIdiom == .carPlay
}
}
使用
if UIDevice.isPad {
// Do something
}
当使用Swift时,你可以使用enum UIUserInterfaceIdiom,定义为:
enum UIUserInterfaceIdiom : Int {
case unspecified
case phone // iPhone and iPod touch style UI
case pad // iPad style UI (also includes macOS Catalyst)
}
所以你可以这样使用它:
UIDevice.current.userInterfaceIdiom == .pad
UIDevice.current.userInterfaceIdiom == .phone
UIDevice.current.userInterfaceIdiom == .unspecified
或者使用Switch语句:
switch UIDevice.current.userInterfaceIdiom {
case .phone:
// It's an iPhone
case .pad:
// It's an iPad (or macOS Catalyst)
@unknown default:
// Uh, oh! What could it be?
}
UI_USER_INTERFACE_IDIOM()是一个Objective-C宏,它被定义为:
#define UI_USER_INTERFACE_IDIOM() \ ([[UIDevice currentDevice] respondsToSelector:@selector(userInterfaceIdiom)] ? \ [[UIDevice currentDevice] userInterfaceIdiom] : \ UIUserInterfaceIdiomPhone)
还要注意,即使在使用Objective-C时,UI_USER_INTERFACE_IDIOM()宏也只在针对iOS 3.2及以下时才需要。当部署到iOS 3.2及以上版本时,可以直接使用[UIDevice userInterfaceIdiom]。
如果寇/换:
if UIDevice.current.userInterfaceIdiom == .pad {
// iPad
} else {
// not iPad (iPhone, mac, tv, carPlay, unspecified)
}
你可以在Swift 5上使用新的方式:
switch traitCollection.userInterfaceIdiom {
case .unspecified:
// do something
case .phone:
// do something
case .pad:
// do something
case .tv:
// do something
case .carPlay:
// do something
case .mac:
// do something
@unknown default:
// do something
}
试试这个检查当前设备是iPhone还是iPad:
斯威夫特5
struct Device {
static let IS_IPAD = UIDevice.current.userInterfaceIdiom == .pad
static let IS_IPHONE = UIDevice.current.userInterfaceIdiom == .phone
}
Use:
if(Device.IS_IPHONE){
// device is iPhone
}if(Device.IS_IPAD){
// device is iPad (or a Mac running under macOS Catalyst)
}else{
// other
}