Swift Constant File

//Update 0729

`dlog` 更新：[http://www.jianshu.com/p/e65d7c661741]

整理下 Swift 中常用的 Constant.swift 文件

import UIKit

extension String {

var floatValue: Float {

return (self as NSString).floatValue

}

}

extension String {

func stringByAppendingPathComponent(path: String) -> String {

let nsSt = self as NSString

return nsSt.stringByAppendingPathComponent(path)

}

}

//MARK: Screen

let SCREEN_BOUNDS = UIScreen.mainScreen().bounds

let SCREEN_SCALE = UIScreen.mainScreen().scale

let SCREEN_WIDTH = UIScreen.mainScreen().bounds.size.width

let SCREEN_HEIGHT = UIScreen.mainScreen().bounds.size.height

let SCREEN_MAX_LENGTH = max(SCREEN_WIDTH, SCREEN_HEIGHT)

let SCREEN_MIN_LENGTH = min(SCREEN_WIDTH, SCREEN_HEIGHT)

//MARK: Device

let IS_IPAD = UIDevice.currentDevice().userInterfaceIdiom == UIUserInterfaceIdiom.Pad

let IS_IPHONE = UIDevice.currentDevice().userInterfaceIdiom == UIUserInterfaceIdiom.Phone

let IS_IPHONE_4_OR_LESS = (IS_IPHONE && SCREEN_MAX_LENGTH < 568.0)

let IS_IPHONE_5 = (IS_IPHONE && SCREEN_MAX_LENGTH == 568.0)

let IS_IPHONE_6 = (IS_IPHONE && SCREEN_MAX_LENGTH == 667.0)

let IS_IPHONE_6P = (IS_IPHONE && SCREEN_MAX_LENGTH == 736.0)

//MARK: System Version

let IS_OS_7_OR_LATER = (UIDevice.currentDevice().systemVersion as String).floatValue >= 7.0

let IS_OS_8_OR_LATER = (UIDevice.currentDevice().systemVersion as String).floatValue >= 8.0

let IS_OS_9_OR_LATER = (UIDevice.currentDevice().systemVersion as String).floatValue >= 9.0

//MARK: Macros

/**

dLog macros to abbreviate NSLog.

Use like this:

dLog(“Log this!”)

**/

#if DEBUG

func dLog(@autoclosure message:  () -> String, filename: String = __FILE__, function: String = __FUNCTION__, line: Int = __LINE__) {

NSLog(“[\(filename.stringByAppendingPathComponent):\(line)] \(function) – %@”, message())

}

#else

func dLog(@autoclosure message:  () -> String, filename: String = __FILE__, function: String = __FUNCTION__, line: Int = __LINE__) {

}

#endif

整理的时候发现，下面的两行代码如果一起放到 Constant.swift  中会导致编辑失败

let IS_IPAD = UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.Pad

let IS_OS_7_OR_LATER = (UIDevice.currentDevice().systemVersion as String).floatValue >= 7.0

错误提示：

IR generation failure: program too clever: variable collides with existing symbol OBJC_CLASS_$_UIDevice

解决方法是将 UI_USER_INTERFACE_IDIOM() 方法替换为

let IS_IPAD = UIDevice.currentDevice().userInterfaceIdiom == UIUserInterfaceIdiom.Pad

因为苹果关于 UI_USER_INTERFACE_IDIOM() 的文档有描述

The UI_USER_INTERFACE_IDIOM() function is provided for use when deploying to a version of the iOS less than 3.2. If the earliest version of iPhone/iOS that you will be deploying for is 3.2 or greater, you may use -[UIDevice userInterfaceIdiom] directly.

另外，dlog 生效需要在 Build Settings – Swift Compiler – Custom Flags – Other Swift Flags 中，Debug 一栏，增加

-D DEBUG

才可以生效

以上