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当我在Swift iOS上绘制时，ImageView的坐标发生了变化

iosswiftimageviewimage-resizing
3
我将遵循这个教程，在应用程序启动时，一切都很好，imagView设置在我设置的位置。但是问题在于，当我开始在imageView上绘画时，imageView的大小会调整到模糊的坐标，并且它会变大并占用太多空间，导致视图不清晰，即使我已经设置了自动布局。 也许我漏掉了什么，以下是代码：
import UIKit
import CoreImage

class ViewController: UIViewController {

let imageNameIs = "BradPitImage"
var lastPoint = CGPoint.zero
var red: CGFloat = 0.0
var green: CGFloat = 0.0
var blue: CGFloat = 0.0
var brushWidth: CGFloat = 10.0
var opacity: CGFloat = 1.0
var swiped = false

@IBOutlet weak var tempImageView: UIImageView!
var tempImageViewtemp : UIImageView = UIImageView()

@IBOutlet weak var resetButton: UIButton!
@IBOutlet weak var saveButton: UIButton!

@IBAction func resetAct(_ sender: Any) {
    tempImageView.image = nil
    tempImageView.image = UIImage(named: imageNameIs)
}

override func viewDidLoad() {
    super.viewDidLoad()
    self.tempImageView.image = UIImage(named: imageNameIs)
}

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    swiped = false
    if let touch = touches.first {
        lastPoint = touch.location(in: self.tempImageView)//view)
    }
}

func drawLineFrom(fromPoint: CGPoint, toPoint: CGPoint) {
    // 1
    UIGraphicsBeginImageContext(view.frame.size)//(tempImageView.frame.size) makes lines coluored of image
    let context = UIGraphicsGetCurrentContext()
    tempImageView.image?.draw(in: CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height))

    // 3
    context!.move(to: fromPoint)
    context!.addLine(to: toPoint)
    context!.setLineCap(.round)
    context!.setLineWidth(brushWidth)
    context!.setStrokeColor(red: red, green: green, blue: blue, alpha: 1)
    context!.setBlendMode(.normal)

    // 4
    context!.strokePath()
    //CGContextStrokePath(context!)

    // 5
    tempImageView.image = UIGraphicsGetImageFromCurrentImageContext()
    tempImageView.alpha = opacity
    UIGraphicsEndImageContext()
}

override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
    swiped = true
    if let touch = touches.first {
        let currentPoint = touch.location(in: view)
        drawLineFrom(fromPoint: lastPoint, toPoint: currentPoint)
    // 7
    lastPoint = currentPoint
    }
}

 func touchesMoved(touches: Set<NSObject>, withEvent event: UIEvent) {
    // 6
    swiped = true
    if let touch = touches.first as? UITouch {
        let currentPoint = touch.location(in: view)
        drawLineFrom(fromPoint: lastPoint, toPoint: currentPoint)
        // 7
        lastPoint = currentPoint
    }
}

override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
    if !swiped {
        //draw a single point
        drawLineFrom(fromPoint: lastPoint, toPoint: lastPoint)
    }
    UIGraphicsBeginImageContext(tempImageViewtemp.frame.size)
    tempImageViewtemp.image?.draw(in: CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height), blendMode: .normal, alpha: 1)
    tempImageView.image?.draw(in: CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height), blendMode: .normal, alpha: opacity)
    tempImageViewtemp.image = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
  }
}

以下是图片：
1）启动时： enter image description here 2）当我开始绘图时： enter image description here **根据DonMag的答案更新，仍有模糊不清的坐标**
它仅适用于纵向方向，问题是当我切换到横向模式并开始绘图时，图像大小会减小到顶部，并在底部增加一定的空白区域，然后我转换到纵向模式时，图像从顶部到底部变得更窄并居中。以下是按照您的代码添加的新截图：
1）从纵向到横向首次转换时： enter image description here 2）当我开始绘图时，它会缩小图像并使绘图变得模糊： enter image description here 现在，从横向启动时，它看起来像这样，并且绘图既不会缩小也不会变模糊： enter image description here 但是，当切换到纵向时，图像会缩小如下： enter image description here
2
这很可能不是你问题的根源，但是当它明显是汤姆·克鲁斯的照片时，将其称为“BradPitImage”似乎是一个问题。 - Ian MacDonald
哈哈哈哈 @IanMacDonald 我不小心做了那件事 :) - Xcodian Solangi
2个回答
3

有几个事情需要注意...

  1. 看起来你的图像视图设置为Aspect Fit缩放。这意味着你的图像与图像视图本身的大小不同。

  2. 你混合了图像视图和根视图的框架大小。

以下是您的代码，经过一些修改。请查看// ---标注的注释。您应该能够替换您当前的代码并直接运行：

import UIKit
import CoreImage

extension UIView {
    // return content of view as a UIImage
    // can be used to get a copy of the rendered image view
    // e.g. the result of scaling setting

    func asImage() -> UIImage {
        let renderer = UIGraphicsImageRenderer(bounds: bounds)
        return renderer.image { rendererContext in
            layer.render(in: rendererContext.cgContext)
        }
    }

}

class ViewController: UIViewController {

    let imageNameIs = "BradPitImage"
    var lastPoint = CGPoint.zero
    var red: CGFloat = 0.0
    var green: CGFloat = 0.0
    var blue: CGFloat = 0.0
    var brushWidth: CGFloat = 10.0
    var opacity: CGFloat = 1.0
    var swiped = false

    @IBOutlet weak var tempImageView: UIImageView!
    var tempImageViewtemp : UIImageView = UIImageView()

    // ---
    // --- this will hold a copy of the resized image (for reset)
    var resizedImage: UIImage!

    @IBOutlet weak var resetButton: UIButton!
    @IBOutlet weak var saveButton: UIButton!

    @IBAction func resetAct(_ sender: Any) {
        // ---
        // --- reset using the resized image from viewDidAppear
        tempImageView.image = resizedImage
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        self.tempImageView.image = UIImage(named: imageNameIs)
    }

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)

        // ---
        // --- create a resized copy of the original image
        // --- (handles aspect fit scale)
        resizedImage = tempImageView.asImage()
        tempImageView.image = resizedImage

    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        swiped = false
        if let touch = touches.first {
            // ---
            // --- get point ** in tempImageView **
            lastPoint = touch.location(in: self.tempImageView)  //view)
        }
    }

    func drawLineFrom(fromPoint: CGPoint, toPoint: CGPoint) {
        // 1

        // ---
        // --- get the bounds of tempImageView
        let rect = tempImageView.bounds

        // ---
        // --- use the bounds for the image context size
        UIGraphicsBeginImageContext(rect.size)

        let context = UIGraphicsGetCurrentContext()

        // ---
        // --- draw the image into the bounds rect
        tempImageView.image?.draw(in: rect)

        // 3
        context!.move(to: fromPoint)
        context!.addLine(to: toPoint)
        context!.setLineCap(.round)
        context!.setLineWidth(brushWidth)
        context!.setStrokeColor(red: red, green: green, blue: blue, alpha: 1)
        context!.setBlendMode(.normal)

        // 4
        context!.strokePath()
        //CGContextStrokePath(context!)

        // 5
        tempImageView.image = UIGraphicsGetImageFromCurrentImageContext()
        tempImageView.alpha = opacity
        UIGraphicsEndImageContext()
    }

    override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
        swiped = true
        if let touch = touches.first {

            // ---
            // --- get point ** in tempImageView **
            let currentPoint = touch.location(in: self.tempImageView)

            drawLineFrom(fromPoint: lastPoint, toPoint: currentPoint)

            // 7
            lastPoint = currentPoint
        }
    }

    override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
        if !swiped {
            //draw a single point
            drawLineFrom(fromPoint: lastPoint, toPoint: lastPoint)
        }

        // ---
        // don't know what you're doing with tempImageViewtemp,
        // but you probably want to change the sizing here to match elsewhere
        UIGraphicsBeginImageContext(tempImageViewtemp.frame.size)
        tempImageViewtemp.image?.draw(in: CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height), blendMode: .normal, alpha: 1)
        tempImageView.image?.draw(in: CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height), blendMode: .normal, alpha: opacity)
        tempImageViewtemp.image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
    }
}

编辑：

这里有一种略微不同的方法，可以让您更进一步。

不要修改您的图像，而是改变imageView的大小以匹配图像的比例。

故事板布局：

enter image description here

ImageView具有保持在白色superview中心的约束，并将受到其宽度和高度的限制，保持比例（纵横比）。

白色视图有约束，使其大小/位置位于按钮上方。

结果-肖像方向，左眼周围画了一个圆圈：

enter image description here

结果-设备旋转到横向方向，右眼周围画了另一个圆圈：

enter image description here

您还可以在代码/注释中注意到，“brushWidth”必须根据图像高度进行调整...仅使用10个点作为宽度会导致当图像较短（横向）时线条变“粗”。

这是代码：

//
//  DrawOnViewController.swift
//
//  Created by Don Mag on 11/7/18.
//

import UIKit

extension NSLayoutConstraint {
    /**
    Change multiplier constraint

    - parameter multiplier: CGFloat
    - returns: NSLayoutConstraint
    */
    func setMultiplier(multiplier:CGFloat) -> NSLayoutConstraint {

        NSLayoutConstraint.deactivate([self])

        let newConstraint = NSLayoutConstraint(
            item: firstItem as Any,
            attribute: firstAttribute,
            relatedBy: relation,
            toItem: secondItem,
            attribute: secondAttribute,
            multiplier: multiplier,
            constant: constant)

        newConstraint.priority = priority
        newConstraint.shouldBeArchived = self.shouldBeArchived
        newConstraint.identifier = self.identifier

        NSLayoutConstraint.activate([newConstraint])
        return newConstraint
    }
}

class DrawOnViewController: UIViewController {

    let imageNameIs = "BradPitImage"
    var lastPoint = CGPoint.zero
    var red: CGFloat = 0.0
    var green: CGFloat = 0.0
    var blue: CGFloat = 0.0
    var brushWidth: CGFloat = 10.0
    var opacity: CGFloat = 1.0
    var swiped = false

    @IBOutlet weak var tempImageView: UIImageView!
    var tempImageViewtemp : UIImageView = UIImageView()

    // ---
    // --- this will hold a reference to the image view's aspect ratio constraint
    @IBOutlet var imageViewAspectRatioConstraint: NSLayoutConstraint!

    // ---
    // --- this will be used to allow "brushWidth" to remain
    // --- constant when device is rotated
    var loadedImageHeight: CGFloat = 0.0

    // ---
    // --- this will be the "brushWidth" relative to
    // --- to the image's originial height
    var adjustedBrushWidth: CGFloat = 0.0

    @IBOutlet weak var resetButton: UIButton!
    @IBOutlet weak var saveButton: UIButton!

    @IBAction func resetAct(_ sender: Any) {
        if let img = UIImage(named: imageNameIs) {
            // ---
            // --- reset the imageView's image
            tempImageView.image = img
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        if let img = UIImage(named: imageNameIs) {

            let imgSize = img.size

            // ---
            // --- calculate the aspect ratio of the image
            let ratio = imgSize.width / imgSize.height

            // ---
            // --- change the image view's aspect ratio to match the image
            imageViewAspectRatioConstraint = imageViewAspectRatioConstraint.setMultiplier(multiplier: ratio)

            // ---
            // --- save original image height for brushWidth adjustment
            loadedImageHeight = imgSize.height

            // ---
            // --- set the imageView's image
            self.tempImageView.image = img

        }

    }

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)

        // ---
        // --- calculate brushWidth relative to image height scaled to image view height
        adjustedBrushWidth = brushWidth * loadedImageHeight / tempImageView.frame.height
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        swiped = false
        if let touch = touches.first {
            // ---
            // --- get point ** in tempImageView **
            lastPoint = touch.location(in: self.tempImageView)
        }
    }

    func drawLineFrom(fromPoint: CGPoint, toPoint: CGPoint) {
        // 1

        // ---
        // --- get the bounds of tempImageView
        let rect = tempImageView.bounds

        // ---
        // --- use the bounds for the image context size
        UIGraphicsBeginImageContext(rect.size)

        let context = UIGraphicsGetCurrentContext()

        // ---
        // --- draw the image into the bounds rect
        tempImageView.image?.draw(in: rect)

        // 3
        context!.move(to: fromPoint)
        context!.addLine(to: toPoint)
        context!.setLineCap(.round)

        // ---
        // --- set line width proportional to current imageView height
        // --- use adjustedBrushWidth set in viewDidAppear
//      context!.setLineWidth(brushWidth * rect.height / loadedImageHeight)
        context!.setLineWidth(adjustedBrushWidth * rect.height / loadedImageHeight)

        context!.setStrokeColor(red: red, green: green, blue: blue, alpha: 1)
        context!.setBlendMode(.normal)

        // 4
        context!.strokePath()
        //CGContextStrokePath(context!)

        // 5
        tempImageView.image = UIGraphicsGetImageFromCurrentImageContext()
        tempImageView.alpha = opacity
        UIGraphicsEndImageContext()
    }

    override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
        swiped = true
        if let touch = touches.first {

            // ---
            // --- get point ** in tempImageView **
            let currentPoint = touch.location(in: self.tempImageView)

            drawLineFrom(fromPoint: lastPoint, toPoint: currentPoint)

            // 7
            lastPoint = currentPoint
        }
    }

    override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
        if !swiped {
            //draw a single point
            drawLineFrom(fromPoint: lastPoint, toPoint: lastPoint)
        }

        // ---
        // don't know what you're doing with tempImageViewtemp,
        // but you probably want to change the sizing here to match elsewhere
        //      UIGraphicsBeginImageContext(tempImageViewtemp.frame.size)
        //      tempImageViewtemp.image?.draw(in: CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height), blendMode: .normal, alpha: 1)
        //      tempImageView.image?.draw(in: CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height), blendMode: .normal, alpha: opacity)
        //      tempImageViewtemp.image = UIGraphicsGetImageFromCurrentImageContext()
        //      UIGraphicsEndImageContext()
    }
}

以下是带有必要约束条件的故事板：

<?xml version="1.0" encoding="UTF-8"?>
<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="14109" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="bvb-cu-Gcn">
    <device id="retina4_7" orientation="portrait">
        <adaptation id="fullscreen"/>
    </device>
    <dependencies>
        <deployment identifier="iOS"/>
        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="14088"/>
        <capability name="Aspect ratio constraints" minToolsVersion="5.1"/>
        <capability name="Safe area layout guides" minToolsVersion="9.0"/>
        <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
    </dependencies>
    <scenes>
        <!--Draw On View Controller-->
        <scene sceneID="b4T-Zn-uEk">
            <objects>
                <viewController id="bvb-cu-Gcn" customClass="DrawOnViewController" customModule="SW4Temp" customModuleProvider="target" sceneMemberID="viewController">
                    <view key="view" contentMode="scaleToFill" id="fif-yb-Cf8">
                        <rect key="frame" x="0.0" y="0.0" width="375" height="667"/>
                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                        <subviews>
                            <view contentMode="scaleToFill" translatesAutoresizingMaskIntoConstraints="NO" id="GU5-HP-5fd">
                                <rect key="frame" x="8" y="28" width="359" height="593"/>
                                <subviews>
                                    <imageView clipsSubviews="YES" userInteractionEnabled="NO" contentMode="scaleToFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" translatesAutoresizingMaskIntoConstraints="NO" id="1MQ-UT-8dQ">
                                        <rect key="frame" x="0.5" y="117.5" width="358.5" height="358.5"/>
                                        <color key="backgroundColor" red="1" green="0.1857388616" blue="0.57339501380000002" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                                        <constraints>
                                            <constraint firstAttribute="width" secondItem="1MQ-UT-8dQ" secondAttribute="height" multiplier="1:1" id="xD6-8c-1AI"/>
                                        </constraints>
                                    </imageView>
                                </subviews>
                                <color key="backgroundColor" white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
                                <constraints>
                                    <constraint firstItem="1MQ-UT-8dQ" firstAttribute="height" secondItem="GU5-HP-5fd" secondAttribute="height" priority="750" id="14p-DB-cE1"/>
                                    <constraint firstAttribute="bottom" relation="greaterThanOrEqual" secondItem="1MQ-UT-8dQ" secondAttribute="bottom" id="9A8-ey-EzV"/>
                                    <constraint firstItem="1MQ-UT-8dQ" firstAttribute="leading" relation="greaterThanOrEqual" secondItem="GU5-HP-5fd" secondAttribute="leading" id="DbB-Mv-lEx"/>
                                    <constraint firstItem="1MQ-UT-8dQ" firstAttribute="top" relation="greaterThanOrEqual" secondItem="GU5-HP-5fd" secondAttribute="top" id="Eq0-pn-RKN"/>
                                    <constraint firstItem="1MQ-UT-8dQ" firstAttribute="centerY" secondItem="GU5-HP-5fd" secondAttribute="centerY" id="d9A-Un-06B"/>
                                    <constraint firstAttribute="trailing" relation="greaterThanOrEqual" secondItem="1MQ-UT-8dQ" secondAttribute="trailing" id="dDp-HC-4pn"/>
                                    <constraint firstItem="1MQ-UT-8dQ" firstAttribute="centerX" secondItem="GU5-HP-5fd" secondAttribute="centerX" id="mqJ-4L-wQR"/>
                                </constraints>
                            </view>
                            <button opaque="NO" contentMode="scaleToFill" horizontalHuggingPriority="1000" verticalHuggingPriority="1000" horizontalCompressionResistancePriority="1000" verticalCompressionResistancePriority="1000" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="QmC-N4-hsp">
                                <rect key="frame" x="20" y="629" width="39" height="30"/>
                                <color key="backgroundColor" red="0.99953407049999998" green="0.98835557699999999" blue="0.47265523669999998" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                                <state key="normal" title="Reset"/>
                                <connections>
                                    <action selector="resetAct:" destination="bvb-cu-Gcn" eventType="touchUpInside" id="5ug-cY-v6A"/>
                                </connections>
                            </button>
                            <button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="BWU-rw-ePF">
                                <rect key="frame" x="321" y="629" width="34" height="30"/>
                                <color key="backgroundColor" red="0.99953407049999998" green="0.98835557699999999" blue="0.47265523669999998" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                                <state key="normal" title="Save"/>
                                <connections>
                                    <action selector="resetAct:" destination="bvb-cu-Gcn" eventType="touchUpInside" id="JkQ-M7-brY"/>
                                </connections>
                            </button>
                            <button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="sia-an-mGC">
                                <rect key="frame" x="168.5" y="629" width="37" height="30"/>
                                <color key="backgroundColor" red="0.99953407049999998" green="0.98835557699999999" blue="0.47265523669999998" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                                <state key="normal" title="Color"/>
                            </button>
                        </subviews>
                        <color key="backgroundColor" red="1" green="0.83234566450000003" blue="0.47320586440000001" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                        <constraints>
                            <constraint firstItem="mdN-5j-gOT" firstAttribute="bottom" secondItem="sia-an-mGC" secondAttribute="bottom" constant="8" id="33Q-9r-cik"/>
                            <constraint firstItem="mdN-5j-gOT" firstAttribute="bottom" secondItem="BWU-rw-ePF" secondAttribute="bottom" constant="8" id="9Xw-wi-cSH"/>
                            <constraint firstItem="mdN-5j-gOT" firstAttribute="trailing" secondItem="BWU-rw-ePF" secondAttribute="trailing" constant="20" id="Bwp-Uu-Qt7"/>
                            <constraint firstItem="GU5-HP-5fd" firstAttribute="top" secondItem="mdN-5j-gOT" secondAttribute="top" constant="8" id="E63-DW-lHC"/>
                            <constraint firstItem="mdN-5j-gOT" firstAttribute="trailing" secondItem="GU5-HP-5fd" secondAttribute="trailing" constant="8" id="GDF-yb-Zhr"/>
                            <constraint firstItem="GU5-HP-5fd" firstAttribute="leading" secondItem="mdN-5j-gOT" secondAttribute="leading" constant="8" id="Pw9-SO-lkd"/>
                            <constraint firstItem="mdN-5j-gOT" firstAttribute="bottom" secondItem="QmC-N4-hsp" secondAttribute="bottom" constant="8" id="TKU-Ht-CmQ"/>
                            <constraint firstItem="QmC-N4-hsp" firstAttribute="leading" secondItem="mdN-5j-gOT" secondAttribute="leading" constant="20" id="Uwc-k4-TP4"/>
                            <constraint firstItem="QmC-N4-hsp" firstAttribute="top" secondItem="GU5-HP-5fd" secondAttribute="bottom" constant="8" id="ute-8t-Q2P"/>
                            <constraint firstItem="sia-an-mGC" firstAttribute="centerX" secondItem="fif-yb-Cf8" secondAttribute="centerX" id="zXd-nm-Goa"/>
                        </constraints>
                        <viewLayoutGuide key="safeArea" id="mdN-5j-gOT"/>
                    </view>
                    <connections>
                        <outlet property="imageViewAspectRatioConstraint" destination="xD6-8c-1AI" id="KWT-aA-gtN"/>
                        <outlet property="tempImageView" destination="1MQ-UT-8dQ" id="brX-iu-UgX"/>
                    </connections>
                </viewController>
                <placeholder placeholderIdentifier="IBFirstResponder" id="zoz-eV-W9h" userLabel="First Responder" sceneMemberID="firstResponder"/>
            </objects>
            <point key="canvasLocation" x="48.799999999999997" y="624.73763118440786"/>
        </scene>
    </scenes>
</document>
亲爱的，我已经实现了您建议的解决方案，但它只适用于纵向方向。问题是当我切换到横向模式并开始绘图时，图像尺寸会缩小到顶部，并且底部会出现越来越多的空白区域。然后我再切换回纵向模式时，图像从上到下变得更窄，居中显示。我已根据您的代码添加了新的截图。 - Xcodian Solangi
@XcodianSolangi - 这并不是“最终代码”的意图。它只是为了解释为什么你的代码无法工作。你需要做额外的工作来处理设备旋转（和其他任务）。 - DonMag
@XcodianSolangi - 我添加了另一种方法，希望能让你更进一步。请查看我的编辑后的答案。 - DonMag
你好 @DonMag，我遇到了一个错误：“由于未捕获的异常NSUnknownKeyException，应用程序终止，原因是“[<UIViewController 0x7fa4175086c0>] setValue:forUndefinedKey:]：这个类没有为key imageViewAspectRatioConstraint编写键值编码兼容性。” - Xcodian Solangi
@XcodianSolangi - 你是否使用我发布的类代码和Storyboard源文件？如果是这样，它应该可以直接运行。如果你正在编辑另一个Storyboard，请确保已经为你的ImageView添加了一个Aspect Ratio约束，并将其连接到@IBOutlet var imageViewAspectRatioConstraint: NSLayoutConstraint!。 - DonMag
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tempImageView.image?.draw(in: CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height))

这行代码指定使用self.view的尺寸进行绘制。这将导致图像失真，因为图像的宽高比与self.view不同。

用下面的代码替换以上代码应该可以解决问题。

 tempImageView.image?.draw(in: tempImageView.bounds)

在你使用“draw”方法的任何地方进行类似的更改。
已经在各处进行了更改，但仍然发现ImageView坐标以相同的方式更改。 - Xcodian Solangi
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