Question

我在段落中添加了解更多/更少文字时遇到问题。该文需要iPod，但不需要iPad。请查看下面的附件。

<第一个问题是指在点击＆＃34; Read More＆＃34;之前按钮，左上角有一个空格。当我点击“阅读更多”按钮时，标签将转到顶部并且没有空格。

第二个问题是，如果设备 iPad ，则“阅读更多”按钮不需要，因为屏幕尺寸很大并且显示所有文本。
对于 iPod ，它需要有该按钮。

这是我的代码。

func getLabelHeight(text: String, width: CGFloat, font: UIFont) -> CGFloat {
    let lbl = UILabel(frame: .zero)
    lbl.frame.size.width = width
    lbl.font = font
    lbl.numberOfLines = 0
    lbl.text = text
    lbl.sizeToFit()

    return lbl.frame.size.height
}

@IBAction func btnReadMore(_ sender: Any) {
    if isLabelAtMaxHeight {
        btnReadmore.setTitle("Read more", for: .normal)
        isLabelAtMaxHeight = false
        lblReviewHeight.constant = 93
    }
    else {
        btnReadmore.setTitle("Read less", for: .normal)
        isLabelAtMaxHeight = true
        lblReviewHeight.constant = getLabelHeight(text: lblReview.text!, width: view.bounds.width, font: lblReview.font)

    }

}

如果需要阅读按钮，我该如何检查？请帮我。我不想添加任何其他库文件。

Answer 1

您可以使用以下代码识别设备（从here获取）

import UIKit

public extension UIDevice {

    var modelName: String {
        var systemInfo = utsname()
        uname(&systemInfo)
        let machineMirror = Mirror(reflecting: systemInfo.machine)
        let identifier = machineMirror.children.reduce("") { identifier, element in
            guard let value = element.value as? Int8, value != 0 else { return identifier }
            return identifier + String(UnicodeScalar(UInt8(value)))
        }

        switch identifier {
        case "iPod5,1":                                 return "iPod Touch 5"
        case "iPod7,1":                                 return "iPod Touch 6"
        case "iPhone3,1", "iPhone3,2", "iPhone3,3":     return "iPhone 4"
        case "iPhone4,1":                               return "iPhone 4s"
        case "iPhone5,1", "iPhone5,2":                  return "iPhone 5"
        case "iPhone5,3", "iPhone5,4":                  return "iPhone 5c"
        case "iPhone6,1", "iPhone6,2":                  return "iPhone 5s"
        case "iPhone7,2":                               return "iPhone 6"
        case "iPhone7,1":                               return "iPhone 6 Plus"
        case "iPhone8,1":                               return "iPhone 6s"
        case "iPhone8,2":                               return "iPhone 6s Plus"
        case "iPhone9,1", "iPhone9,3":                  return "iPhone 7"
        case "iPhone9,2", "iPhone9,4":                  return "iPhone 7 Plus"
        case "iPhone8,4":                               return "iPhone SE"
        case "iPad2,1", "iPad2,2", "iPad2,3", "iPad2,4":return "iPad 2"
        case "iPad3,1", "iPad3,2", "iPad3,3":           return "iPad 3"
        case "iPad3,4", "iPad3,5", "iPad3,6":           return "iPad 4"
        case "iPad4,1", "iPad4,2", "iPad4,3":           return "iPad Air"
        case "iPad5,3", "iPad5,4":                      return "iPad Air 2"
        case "iPad2,5", "iPad2,6", "iPad2,7":           return "iPad Mini"
        case "iPad4,4", "iPad4,5", "iPad4,6":           return "iPad Mini 2"
        case "iPad4,7", "iPad4,8", "iPad4,9":           return "iPad Mini 3"
        case "iPad5,1", "iPad5,2":                      return "iPad Mini 4"
        case "iPad6,3", "iPad6,4", "iPad6,7", "iPad6,8":return "iPad Pro"
        case "AppleTV5,3":                              return "Apple TV"
        case "i386", "x86_64":                          return "Simulator"
        default:                                        return identifier
        }
    }

}

// Swift 3 let modelName = UIDevice.current.modelName

然后你可以使用if，else ..

if(modelName == iPad 3 || modelName == iPad 4 ||modelName == iPad Air){

   // No Read More button

}else{
  // Add Read More button
}

如何使用Swift 3在段落中添加更多/更少？

1 个答案: