如何在xcode中的图像上叠加图像？答案

【问题标题】：how to overlay an image over an image in xcode?如何在xcode中的图像上叠加图像？
【发布时间】：2016-01-09 05:47:15
【问题描述】：

我正在尝试制作一个应用程序，用户可以在其中从他们的图片库中选择一张将用作背景的图片，然后是他们的徽标，他们也可以从他们的（照片）库中选择...

目前我还没有找到可以帮助我的教程，主要是因为用户必须能够设置自己的图像而不是默认图像。另外，你们中的任何人是否也知道我如何拥有多个 UIImagePickerControllers，因为这段代码会同时影响两个图像而不是每个选择器一个？

我使用/拥有什么：
我用 swift
我使用 xcode 7.0.1
这是 the storyboard i currently use.

我的快速文件：

class ViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {

  @IBOutlet weak var logo: UIImageView!
  @IBOutlet weak var bgimg: UIImageView!

  override func viewDidLoad() {
    super.viewDidLoad()
  }

  @IBAction func selectbg(sender: AnyObject) {
    let bgPicker = UIImagePickerController()
    bgPicker.delegate = self
    bgPicker.sourceType = .PhotoLibrary
    self.presentViewController(bgPicker, animated: true, completion: nil)
  }

  @IBAction func selectlogo(sender: AnyObject) {
    let logoPicker = UIImagePickerController()
    logoPicker.delegate = self
    logoPicker.sourceType = .PhotoLibrary
    self.presentViewController(logoPicker, animated: true, completion: nil)
  }

  func imagePickerController(picker: UIImagePickerController, didFinishPickingImage image: UIImage, editingInfo: [String : AnyObject]?) {
    logo.image = image
    bgimg.image = image
    self.dismissViewControllerAnimated(false, completion: nil)
  }


  @IBAction func addImage(sender: AnyObject) {

    let ActionAlert = UIAlertController(title: nil, message: "What image do you want to add/edit?", preferredStyle: .ActionSheet)

    let bgimage = UIAlertAction(title: "Background", style: .Default, handler: { (Alert:UIAlertAction!) -> Void in
        print("Edit background image")
    })
    let logo = UIAlertAction(title: "Logo", style: .Default) { (Alert:UIAlertAction!) -> Void in
        print("Edit logo")
    }
    let cancel = UIAlertAction(title: "Cancel", style: .Cancel) { (Alert:UIAlertAction!) -> Void in
        print("remove menu")
    }

    ActionAlert.addAction(bgimage)
    ActionAlert.addAction(logo)
    ActionAlert.addAction(cancel)

    self.presentViewController(ActionAlert, animated: true, completion: nil)
}

}

如果我不清楚我的问题，请随时询问更多信息

【问题讨论】：

标签： ios image swift overlay photolibrary

【解决方案1】：

为每个图像创建两个 UIImageView，并将前景的一个作为子视图添加到父级。

类似这样的：

let bgimg = UIImage(named: "image-name") // The image used as a background
let bgimgview = UIImageView(image: bgimg) // Create the view holding the image
bgimgview.frame = CGRect(x: 0, y: 0, width: 500, height: 500) // The size of the background image

let frontimg = UIImage(named: "front-image") // The image in the foreground
let frontimgview = UIImageView(image: frontimg) // Create the view holding the image
frontimgview.frame = CGRect(x: 150, y: 300, width: 50, height: 50) // The size and position of the front image

bgimgview.addSubview(frontimgview) // Add the front image on top of the background

【讨论】：

美丽。谢谢你的回答！

【解决方案2】：

这是将页脚图像合并到原始图像的示例代码

extension UIImage{
    func merge(mergewith:UIImage) -> UIImage {
        
        UIGraphicsBeginImageContextWithOptions(size, false, 0.0)
        let actualArea = CGRect(x: 0, y: 0, width: size.width, height: size.height)
        let mergeArea = CGRect(x: 0, y: size.height - mergewith.size.height, width: size.width, height: mergewith.size.height)
        self.draw(in: actualArea)
        mergewith.draw(in: mergeArea)
        let merged = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()
        return merged
    }
}

【讨论】：