您好我在一个应用程序中构建，允许用户使用他们的手指在图像上绘制一条线，我的问题是，当用户触摸屏幕开始绘制图像扩展，使图像成为扭曲。
以下是ViewController的代码：
更新：代码已更新，尝试使用第二张图片视图以及来自MailE的建议
import UIKit
import MobileCoreServices
class NewAutographViewControler: UIViewController, UINavigationControllerDelegate, UIImagePickerControllerDelegate, UIGestureRecognizerDelegate {
var signEditMode: Bool = false
@IBOutlet var btnEdit: UIBarButtonItem!
@IBOutlet var textFieldAlbum: UITextField!
@IBOutlet var imageView: UIImageView!
@IBOutlet var signImageView: UIImageView!
@IBAction func btnBackClick(sender: AnyObject) {
self.navigationController?.popViewControllerAnimated(true)
}
@IBAction func btnEditClick(sender: AnyObject) {
if signEditMode {
signEditMode = false
signImageView.backgroundColor = nil
btnEdit.title = "Edit"
signImageView.gestureRecognizers?.removeAll()
}
else {
signEditMode = true
btnEdit.title = "Done"
signImageView.backgroundColor = UIColor(white: 1, alpha: 0.5)
let tap = UIPanGestureRecognizer(target: self, action: Selector("handleTap:"))
tap.delegate = self
signImageView.userInteractionEnabled = true
signImageView.addGestureRecognizer(tap)
}
}
func handleTap(sender: UIPanGestureRecognizer? = nil) {
let recognizer:UIPanGestureRecognizer = sender!
let translation = recognizer.translationInView(self.view)
if let view = recognizer.view {
view.center = CGPoint(x:view.center.x + translation.x,
y:view.center.y + translation.y)
}
recognizer.setTranslation(CGPointZero, inView: self.view)
}
func getSaveResponse( response: Bool){
dispatch_async(dispatch_get_main_queue()) {
print("getSaveResponse")
print(response)
if response {
let alert = UIAlertController(title: "Save", message: "Autograph Saved!", preferredStyle: .Alert)
let save = UIAlertAction(title: "New", style: .Default) { (alertAction: UIAlertAction!) ->
Void in
self.newPhoto()
}
let done = UIAlertAction(title: "Done", style: .Default) { (alertAction: UIAlertAction!) ->
Void in
self.btnBackClick(self)
}
alert.addAction(save)
alert.addAction(done)
self.presentViewController(alert, animated: true, completion: nil)
}
else {
let alert = UIAlertController(title: "Save", message: "Uh Oh! Autograph could not be save!", preferredStyle: .Alert)
alert.addAction(UIAlertAction(title: "Ok", style: .Default, handler: nil))
self.presentViewController(alert, animated: true, completion: nil)
}
}
}
@IBAction func btnSaveClick(sender: AnyObject) {
print("save click")
mergeImages()
let newPhotoAlbum = PhotoAlbum()
let validate = newPhotoAlbum.saveImage(imageView.image!, funParam: getSaveResponse)
if validate == false {
getSaveResponse(false)
}
}
//drawing variables
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
var imageSize: CGSize = CGSize(width: 0,height: 0)
//end-drawing variables
override func viewDidLoad() {
super.viewDidLoad()
newPhoto()
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func newPhoto() {
if (UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.Camera)){
let picker = UIImagePickerController()
picker.delegate = self
picker.sourceType = UIImagePickerControllerSourceType.Camera
//picker.mediaTypes = [kUTTypeImage as String]
//picker.allowsEditing = true
self.presentViewController(picker, animated: true, completion: nil)
}
else {
let alertController = UIAlertController(title: "Camera Error", message: "No Camera Detected!", preferredStyle: UIAlertControllerStyle.Alert)
//alertController.addAction(UIAlertAction(title: "Dismiss", style: UIAlertActionStyle.Default,handler: nil))
let dismiss = UIAlertAction(title: "Dismiss", style: UIAlertActionStyle.Default) { (alertAction: UIAlertAction!) ->
Void in
self.navigationController?.popViewControllerAnimated(true)
}
alertController.addAction(dismiss)
self.presentViewController(alertController, animated: true, completion: nil)
}
}
func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]){
print("Received image from camera")
//let mediaType = info[UIImagePickerControllerMediaType] as! String
var originalImage:UIImage? //, editedImage:UIImage?, imageToSave:UIImage?
//let compResult:CFComparisonResult = CFStringCompare(mediaType as NSString!, kUTTypeImage, CFStringCompareFlags.CompareCaseInsensitive)
//if ( compResult == CFComparisonResult.CompareEqualTo ) {
//editedImage = info[UIImagePickerControllerEditedImage] as! UIImage?
originalImage = info[UIImagePickerControllerOriginalImage] as! UIImage?
/*if ( editedImage != nil ) {
imageToSave = editedImage
} else {
imageToSave = originalImage
}
imageView.image = imageToSave
imageView.reloadInputViews()
}*/
imageView.image = originalImage
picker.dismissViewControllerAnimated(true, completion: nil)
imageSize = (originalImage?.size)!
//print(imageView.frame.size)
}
func imagePickerControllerDidCancel(picker: UIImagePickerController) {
picker.dismissViewControllerAnimated(true, completion: nil)
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
//drawing-functions
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
if signEditMode {
return
}
swiped = false
if let touch:UITouch = touches.first! as UITouch {
//lastPoint = touch.locationInView(self.view)
lastPoint = touch.locationInView(signImageView)
}
}
func drawLineFrom(fromPoint: CGPoint, toPoint: CGPoint) {
/*var scale: CGFloat = 1.0;
if UIScreen.mainScreen().respondsToSelector(Selector("scale")) {
let tmp: CGFloat = UIScreen.mainScreen().scale
if (tmp > 1.5) {
scale = 2.0;
}
}
if(scale > 1.5) {
UIGraphicsBeginImageContextWithOptions(view.frame.size, false, scale);
} else {
UIGraphicsBeginImageContext(view.frame.size);
}
print(imageView.frame.size)
*/
// 1
//UIGraphicsBeginImageContext(view.frame.size)
//UIGraphicsBeginImageContext(self.imageView.frame.size)
UIGraphicsBeginImageContextWithOptions(self.signImageView.bounds.size, false, 0)
let context = UIGraphicsGetCurrentContext()
//tempImageView.image?.drawInRect(CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height))
//imageView.image?.drawInRect(CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height))
signImageView.image?.drawInRect(CGRect(x: 0, y: 0, width: self.signImageView.bounds.size.width, height: self.signImageView.bounds.size.height))
// 2
CGContextMoveToPoint(context, fromPoint.x, fromPoint.y)
CGContextAddLineToPoint(context, toPoint.x, toPoint.y)
// 3
CGContextSetLineCap(context, .Round)
CGContextSetLineWidth(context, brushWidth)
CGContextSetRGBStrokeColor(context, red, green, blue, 1.0)
CGContextSetBlendMode(context, .Normal)
// 4
CGContextStrokePath(context)
// 5
//tempImageView.image = UIGraphicsGetImageFromCurrentImageContext()
//tempImageView.alpha = opacity
//imageView.autoresizingMask = [.FlexibleRightMargin, .FlexibleLeftMargin, .FlexibleBottomMargin, .FlexibleTopMargin]
//Change from Fit to Fill
//imageView.contentMode = UIViewContentMode.ScaleAspectFill
signImageView.image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
}
override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
// 6
swiped = true
if let touch:UITouch = touches.first! as UITouch {
//let currentPoint = touch.locationInView(view)
let currentPoint = touch.locationInView(signImageView)
drawLineFrom(lastPoint, toPoint: currentPoint)
// 7
lastPoint = currentPoint
}
}
override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
if signEditMode {
return
}
if !swiped {
// draw a single point
drawLineFrom(lastPoint, toPoint: lastPoint)
}
// Merge tempImageView into mainImageView
/*UIGraphicsBeginImageContext(imageView.frame.size)
imageView.image?.drawInRect(CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height), blendMode: .Normal, alpha: 1.0)
imageView.image?.drawInRect(CGRect(x: 0, y: 0, width: view.frame.size.width, height: view.frame.size.height), blendMode: .Normal, alpha: opacity)
imageView.image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
tempImageView.image = nil*/
}
//end-drawing-functions
//To Merge Sign and Image
func mergeImages(){
UIGraphicsBeginImageContextWithOptions(imageView.bounds.size, false, 0)
imageView.image?.drawInRect(CGRect(x: 0, y: 0, width: imageView.bounds.size.width, height: imageView.bounds.size.height), blendMode: .Normal, alpha: 1.0)
signImageView.image?.drawInRect(CGRect(x: 0, y: 0, width: imageView.bounds.size.width, height: imageView.bounds.size.height), blendMode: .Normal, alpha: opacity)
//added contentMode
imageView.contentMode = UIViewContentMode.ScaleAspectFill
imageView.image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
signImageView.image = nil
}
}
请问代码有什么问题？
答案 0 :(得分：0)
当您的设备支持视网膜或UIScreen.mainScreen（）。nativeScale＆gt;时，可能会出现问题。 1
尝试
UIGraphicsBeginImageContextWithOptions(self.imageView.bounds.size, false, 0.0)
而不是
UIGraphicsBeginImageContext(self.imageView.frame.size)