Swift:如何从其他视图更改视图的背景 [英] Swift: How to change views' background from other views
问题描述
我的任务是创建一个可以更改和保存背景的应用程序.我想做些更复杂的事情，所以我决定创建一个颜色菜单，让我可以更改所有视图的背景.现在，我有了菜单，而且我知道如何在背景中设置和保存图片/颜色.但是我不知道如何从视图控制器到另一个.现在，我的代码更改了其自己的视图背景.这是我的代码(我知道很多...):
My task is to create an app where I can change and save the background. I wanted to do something more elaborate, so I decided to create a color menu that allows me to change all of the views' backgrounds. Now, I have the menu, and I know how to set and save pictures/ colours in the background. But I don't know how to do it from a view controller to another. Right now my code changes its own view's background. This is my code (I know it's a lot...):
首先，我有2个扩展名，这些扩展名使我可以:1)使用用户默认值保存UIColor； 2)使用rgb颜色:
First of all I have 2 extensions that allows me to 1) save the UIColor with user defaults; 2) use rgb colours:
//MARK: - Extension for rgb
extension UIColor {
convenience init(red: Int, green: Int, blue: Int) {
assert(red >= 0 && red <= 255, "Invalid red component")
assert(green >= 0 && green <= 255, "Invalid green component")
assert(blue >= 0 && blue <= 255, "Invalid blue component")
self.init(red: CGFloat(red) / 255.0, green: CGFloat(green) / 255.0, blue: CGFloat(blue) / 255.0, alpha: 1.0)
}
convenience init(rgb: Int) {
self.init(
red: (rgb >> 16) & 0xFF,
green: (rgb >> 8) & 0xFF,
blue: rgb & 0xFF
)
}
}
//MARK: - Extension to save colors
extension UserDefaults {
func setColor(color: UIColor?, forKey key: String) {
var colorData: NSData?
if let color = color {
do {
colorData = try NSKeyedArchiver.archivedData(withRootObject: color, requiringSecureCoding: false) as NSData?
set(colorData, forKey: key)
} catch let error {
print("error archiving color data", error)
}
}
}
func colorForKey(key: String) -> UIColor? {
var color: UIColor?
if let colorData = data(forKey: "Background") {
do{
color = try NSKeyedUnarchiver.unarchivedObject(ofClass: UIColor.self, from: colorData)
} catch let error {
print("error unarchivig color data", error)
}
}
return color
}
}
我的viewDidLoad:
My viewDidLoad:
var defaults = UserDefaults.standard
private let backgroundKey = "backg"
override func viewDidLoad() {
super.viewDidLoad()
//MARK: - Background Settings
let color = defaults.colorForKey(key: backgroundKey)
view.backgroundColor = color
if let backgroundImage = self.getSavedBackgroundImage() {
self.backgroundImageView.image = backgroundImage
}
}
允许我将图片设置为背景的代码
Code that allows me to set a picture as background
@IBOutlet weak var backgroundImageView: UIImageView!
//I KNOW THIS HAS TO BE PUT IN THE VC WHERE I WANT THE BACKGROUND TO BE CHANGED
@IBAction func pictureButton(_ sender: Any) {
let imagePicker = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = .photoLibrary
imagePicker.allowsEditing = false
present(imagePicker, animated: true, completion: nil)
}
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
if let image = info[UIImagePickerController.InfoKey.originalImage] as? UIImage {
backgroundImageView.image = image
let _ = self.saveBackgroundImage(image: image)
}
self.dismiss(animated: true, completion: nil)
}
func saveBackgroundImage(image: UIImage) -> Bool {
guard let data = image.pngData() ?? backgroundImageView.image?.pngData() else {
return false
}
guard let directory = FileManager.default.urls(for: .documentDirectory,
in: .userDomainMask).first else {
return false
}
do {
try data.write(to: directory.appendingPathComponent("MainBackgroound.png"))
return true
} catch {
print(error.localizedDescription)
return false
}
}
func getSavedBackgroundImage() -> UIImage? {
if let dir = FileManager.default.urls(for: .documentDirectory,
in: .userDomainMask).first {
return UIImage(contentsOfFile: URL(fileURLWithPath: dir.absoluteString).appendingPathComponent("MainBackgroound.png").path)
}
return nil
}
func deleteImage() {
let fileManager = FileManager.default
let yourProjectImagesPath = (NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] as NSString).appendingPathComponent("MainBackgroound.png")
if fileManager.fileExists(atPath: yourProjectImagesPath) {
try! fileManager.removeItem(atPath: yourProjectImagesPath)
}
let yourProjectDirectoryPath = (NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] as NSString).appendingPathComponent("MainBackgroound.png")
if fileManager.fileExists(atPath: yourProjectDirectoryPath) {
try! fileManager.removeItem(atPath: yourProjectDirectoryPath)
}
}
允许我更改背景颜色的代码
Code that allows me to change background's color
@IBAction func lightPinkButton(_ sender: Any) {
self.deleteImage()
let lightPink = UIColor(red: 255, green: 215, blue: 214).withAlphaComponent(1)
defaults.setColor(color: lightPink, forKey: backgroundKey)
view.backgroundColor = lightPink
}
推荐答案
如何创建基本视图控制器(类似于ColorViewController)，并在其中引用背景色，然后从中继承并更新随时随地都可以.
How about you create a base view controller, something like ColorViewController and in there you have a reference to the background color and then just inherit from that and update it wherever you need.
赞
class ColorViewController: UIViewController {
var myBackgroundColor: UIColor = .white
override func viewDidLoad() {
super.viewDidLoad()
}
}
ViewControllerOne
class ViewControllerOne: ColorViewController {
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
view.backgroundColor = myBackgroundColor
}
@IBAction func blueButtonTapped(_ sender: Any) {
myBackgroundColor = .blue
view.backgroundColor = myBackgroundColor
}
}
ViewControllerTwo
class ViewControllerTwo: ColorViewController {
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
view.backgroundColor = myBackgroundColor
}
@IBAction func purpleButton(_ sender: Any) {
myBackgroundColor = .purple
view.backgroundColor = myBackgroundColor
}
}
这篇关于Swift:如何从其他视图更改视图的背景的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
