我的应用程序中有一个场景,我想在两个滑块和用户选择的分段控件之间进行基本数学运算.我试图在分段控件下的变量之间进行数学运算,但是Xcode给了我一个(!)说明
使用未解析的标识符"xxxx"
无论我想添加什么变量.我的代码是:
import UIKit
class DopamineCalculator: UIViewController {
//slider outlets
@IBOutlet weak var slider: UISlider!
@IBOutlet weak var sliderone: UISlider!
//segmentoutlet
@IBOutlet weak var segmentoutlet: UISegmentedControl!
//LABELS
//weight label
@IBOutlet weak var weightlabel: UILabel!
//dosage label
@IBOutlet weak var dosagemg: UILabel!
//Drip Rate Answer Label
@IBOutlet weak var dripanswer: UILabel!
//ACTIONS!!
//weight slider action
@IBAction func weightslider(sender: UISlider) {
let weight = Int(sender.value)
//converts to kgs
let kgs = Int(sender.value) / Int(2.2)
weightlabel.text = "\(weight) lbs"
}
//Dosage Desired …Run Code Online (Sandbox Code Playgroud) 我有一个应用程序,当用户从文本列表视图屏幕按下按钮时,它会显示一堆图片。我有一个特定的子类,允许用户捏合和放大,但我很好奇我需要在我的特定 swift 文件中输入什么代码以允许用户双击放大和缩小。使用此代码时出现三个错误。两个说“'ZoomingScrollView'类型的值没有成员'scrollview'或'imageview'”以及“'CGRectZero'在Swift中不可用”我允许用户放大的子类代码和我的代码一起在下面我正在使用双击缩放。
import UIKit
class ZoomingScrollView: UIScrollView, UIScrollViewDelegate {
@IBOutlet weak var viewForZooming: UIView? = nil {
didSet {
self.delegate = self
} }
func viewForZoomingInScrollView(scrollView: UIScrollView) -> UIView? {
return viewForZooming }
@IBAction func userDoubleTappedScrollview(recognizer: UITapGestureRecognizer) {
if let scrollV = self.scrollview {
if (scrollV.zoomScale > scrollV.minimumZoomScale) {
scrollV.setZoomScale(scrollV.minimumZoomScale, animated: true)
}
else {
//(I divide by 3.0 since I don't wan't to zoom to the max upon the double tap)
let zoomRect = self.zoomRectForScale(scrollV.maximumZoomScale / 3.0, center: …Run Code Online (Sandbox Code Playgroud)