Swift：基於IF更改UIImageView

Question

我想根據我顯示的應用程序的哪一部分來更改UIImageView。

在我的視圖控制器，這個工程設置圖像：

let screenSize = UIScreen.main.bounds 
let screenWidth = screenSize.width 
let screenHeight = screenSize.height 

let imageName = "sectionOneBackground" 
let image = UIImage(named: imageName) 
let imageView = UIImageView(image: image!) 
imageView.frame = CGRect(x: 0, y: 0, width: screenWidth, height: screenHeight) 
view.addSubview(imageView) 

但是，如果我換了圖像中的，如果像這樣：

var imageName = "" 

if (section == "one") { 
    imageName = "sectionOneBackground" 
} 

if (section == "two") { 
    imageName = "sectionTwoBackground" 
} 

if (section == "three") { 
    imageName = "sectionThreeBackground" 
} 

然後，它只是不出現在視圖。我完全錯過了些什麼。沒有這個更簡單的方法來改變視圖的背景嗎？

在此先感謝。

Answer 1

創建ImageView的一個字符串名稱作爲全球

class ViewController: UIViewController 
{ 
var imageView : UIImageView! 
var imageName : String! 

} 

您viewDidLoad中創建的ImageView像

override func viewDidLoad() { 
    super.viewDidLoad() 

    let screenSize = UIScreen.main.bounds 
    let screenWidth = screenSize.width 
    let screenHeight = screenSize.height 

    imageName = "sectionOneBackground" 
    imageView = UIImageView(image: UIImage(named: imageName)!) 
    imageView.frame = CGRect(x: 0, y: 0, width: screenWidth, height: screenHeight) 
    view.addSubview(imageView) 

} 

終於

每當變更ImageView的名稱

if (section == "one") { 
imageName = "sectionOneBackground" 
} 

else if (section == "two") { 
imageName = "sectionTwoBackground" 
} 

else if (section == "three") { 
imageName = "sectionThreeBackground" 
} 
imageView.image = UIImage(named: imageName) 

設定的最終圖像名稱圖像視圖

imageView.image = UIImage(named: imageName)