Mixing
Draw straight line swift 4
-1
maybe a simple question. I am trying to make an app where you can draw straight lines: horizontal vertical and diagonal.
I am also trying to give measurements to the lines (don`t get this working yet..)
I have fixed that I can draw lines but not straight (like a pencil without ruler
can't find any documentation on the web to draw straight lines)
import UIKit
import Foundation
class tekengedeelte: UIViewController, UITextFieldDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
@IBOutlet weak var tekenview: UIView!
var path = UIBezierPath()
var startPoint = CGPoint()
var touchPoint = CGPoint()
var setSigImage: ((_ data: UIImage) -> ())?
var setcameraimage: ((_ data: UIImage) -> ())?
override func viewDidLoad() {
super.viewDidLoad()
tekenview.layer.shadowOpacity = 1
tekenview.layer.shadowRadius = 10
tekenview.layer.shadowOffset = CGSize(width: 1, height: 1)
tekenview.layer.shadowColor = UIColor.black.cgColor
//tekenview.layer.shadowPath = UIBezierPath(rect: tekenview.bounds).cgPath
tekenview.layer.shadowPath = CGPath(rect: tekenview.bounds, transform: nil)
tekenview.layer.shouldRasterize = true
tekenview.clipsToBounds = true
tekenview.isMultipleTouchEnabled = false
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
if let point = touch?.location(in: tekenview) {
startPoint = point
}
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
if let point = touch?.location(in: tekenview) {
touchPoint = point
}
path.move(to: startPoint)
path.addLine(to: touchPoint)
startPoint = touchPoint
draw()
}
func draw() {
let strokeLayer = CAShapeLayer()
strokeLayer.fillColor = UIColor.black.cgColor
strokeLayer.lineWidth = 5
strokeLayer.strokeColor = UIColor.black.cgColor
strokeLayer.path = path.cgPath
tekenview.layer.addSublayer(strokeLayer)
tekenview.setNeedsDisplay()
}
@IBAction func clearPressed(_ sender: UIButton) {
path.removeAllPoints()
tekenview.layer.sublayers = nil
tekenview.setNeedsDisplay()
}
@IBAction func setPressed(_ sender: UIButton) {
// Convert CanvasView to UIImage
let renderer = UIGraphicsImageRenderer(size: tekenview.bounds.size)
let image = renderer.image { ctx in
view.drawHierarchy(in: view.bounds, afterScreenUpdates: true)
}
// Send image back to onboarding screen
setSigImage?(image)
// Rotate device back to portrait mode
//let appDelegate = UIApplication.shared.delegate as! AppDelegate
//appDelegate.r = .portrait
// Close modal window
dismiss(animated: true)
}
//foto maken
@IBAction func camera(_ sender: UIButton) {
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerController.SourceType.camera){
let imagePicker = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = UIImagePickerController.SourceType.camera;
imagePicker.allowsEditing = false
self.present(imagePicker, animated: true, completion: nil)
}
}
@IBAction func photolibraryaction(_ sender: UIButton) {
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerController.SourceType.photoLibrary) {
let imagepicker = UIImagePickerController()
imagepicker.delegate = self
imagepicker.sourceType = UIImagePickerController.SourceType.photoLibrary;
imagepicker.allowsEditing = true
self.present(imagepicker, animated: true, completion: nil)
}
}
}
swift swift4.2
edited Nov 21 '18 at 9:52
Govind Kumawat
715410
asked Nov 20 '18 at 21:47
pepijn Dikpepijn Dik
1
add a comment |
-1
maybe a simple question. I am trying to make an app where you can draw straight lines: horizontal vertical and diagonal.
I am also trying to give measurements to the lines (don`t get this working yet..)
I have fixed that I can draw lines but not straight (like a pencil without ruler
can't find any documentation on the web to draw straight lines)
import UIKit
import Foundation
class tekengedeelte: UIViewController, UITextFieldDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
@IBOutlet weak var tekenview: UIView!
var path = UIBezierPath()
var startPoint = CGPoint()
var touchPoint = CGPoint()
var setSigImage: ((_ data: UIImage) -> ())?
var setcameraimage: ((_ data: UIImage) -> ())?
override func viewDidLoad() {
super.viewDidLoad()
tekenview.layer.shadowOpacity = 1
tekenview.layer.shadowRadius = 10
tekenview.layer.shadowOffset = CGSize(width: 1, height: 1)
tekenview.layer.shadowColor = UIColor.black.cgColor
//tekenview.layer.shadowPath = UIBezierPath(rect: tekenview.bounds).cgPath
tekenview.layer.shadowPath = CGPath(rect: tekenview.bounds, transform: nil)
tekenview.layer.shouldRasterize = true
tekenview.clipsToBounds = true
tekenview.isMultipleTouchEnabled = false
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
if let point = touch?.location(in: tekenview) {
startPoint = point
}
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
if let point = touch?.location(in: tekenview) {
touchPoint = point
}
path.move(to: startPoint)
path.addLine(to: touchPoint)
startPoint = touchPoint
draw()
}
func draw() {
let strokeLayer = CAShapeLayer()
strokeLayer.fillColor = UIColor.black.cgColor
strokeLayer.lineWidth = 5
strokeLayer.strokeColor = UIColor.black.cgColor
strokeLayer.path = path.cgPath
tekenview.layer.addSublayer(strokeLayer)
tekenview.setNeedsDisplay()
}
@IBAction func clearPressed(_ sender: UIButton) {
path.removeAllPoints()
tekenview.layer.sublayers = nil
tekenview.setNeedsDisplay()
}
@IBAction func setPressed(_ sender: UIButton) {
// Convert CanvasView to UIImage
let renderer = UIGraphicsImageRenderer(size: tekenview.bounds.size)
let image = renderer.image { ctx in
view.drawHierarchy(in: view.bounds, afterScreenUpdates: true)
}
// Send image back to onboarding screen
setSigImage?(image)
// Rotate device back to portrait mode
//let appDelegate = UIApplication.shared.delegate as! AppDelegate
//appDelegate.r = .portrait
// Close modal window
dismiss(animated: true)
}
//foto maken
@IBAction func camera(_ sender: UIButton) {
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerController.SourceType.camera){
let imagePicker = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = UIImagePickerController.SourceType.camera;
imagePicker.allowsEditing = false
self.present(imagePicker, animated: true, completion: nil)
}
}
@IBAction func photolibraryaction(_ sender: UIButton) {
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerController.SourceType.photoLibrary) {
let imagepicker = UIImagePickerController()
imagepicker.delegate = self
imagepicker.sourceType = UIImagePickerController.SourceType.photoLibrary;
imagepicker.allowsEditing = true
self.present(imagepicker, animated: true, completion: nil)
}
}
}
swift swift4.2
edited Nov 21 '18 at 9:52
Govind Kumawat
715410
asked Nov 20 '18 at 21:47
pepijn Dikpepijn Dik
1
add a comment |
-1
-1
-1
1
maybe a simple question. I am trying to make an app where you can draw straight lines: horizontal vertical and diagonal.
I am also trying to give measurements to the lines (don`t get this working yet..)
I have fixed that I can draw lines but not straight (like a pencil without ruler
can't find any documentation on the web to draw straight lines)
import UIKit
import Foundation
class tekengedeelte: UIViewController, UITextFieldDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
@IBOutlet weak var tekenview: UIView!
var path = UIBezierPath()
var startPoint = CGPoint()
var touchPoint = CGPoint()
var setSigImage: ((_ data: UIImage) -> ())?
var setcameraimage: ((_ data: UIImage) -> ())?
override func viewDidLoad() {
super.viewDidLoad()
tekenview.layer.shadowOpacity = 1
tekenview.layer.shadowRadius = 10
tekenview.layer.shadowOffset = CGSize(width: 1, height: 1)
tekenview.layer.shadowColor = UIColor.black.cgColor
//tekenview.layer.shadowPath = UIBezierPath(rect: tekenview.bounds).cgPath
tekenview.layer.shadowPath = CGPath(rect: tekenview.bounds, transform: nil)
tekenview.layer.shouldRasterize = true
tekenview.clipsToBounds = true
tekenview.isMultipleTouchEnabled = false
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
if let point = touch?.location(in: tekenview) {
startPoint = point
}
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
if let point = touch?.location(in: tekenview) {
touchPoint = point
}
path.move(to: startPoint)
path.addLine(to: touchPoint)
startPoint = touchPoint
draw()
}
func draw() {
let strokeLayer = CAShapeLayer()
strokeLayer.fillColor = UIColor.black.cgColor
strokeLayer.lineWidth = 5
strokeLayer.strokeColor = UIColor.black.cgColor
strokeLayer.path = path.cgPath
tekenview.layer.addSublayer(strokeLayer)
tekenview.setNeedsDisplay()
}
@IBAction func clearPressed(_ sender: UIButton) {
path.removeAllPoints()
tekenview.layer.sublayers = nil
tekenview.setNeedsDisplay()
}
@IBAction func setPressed(_ sender: UIButton) {
// Convert CanvasView to UIImage
let renderer = UIGraphicsImageRenderer(size: tekenview.bounds.size)
let image = renderer.image { ctx in
view.drawHierarchy(in: view.bounds, afterScreenUpdates: true)
}
// Send image back to onboarding screen
setSigImage?(image)
// Rotate device back to portrait mode
//let appDelegate = UIApplication.shared.delegate as! AppDelegate
//appDelegate.r = .portrait
// Close modal window
dismiss(animated: true)
}
//foto maken
@IBAction func camera(_ sender: UIButton) {
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerController.SourceType.camera){
let imagePicker = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = UIImagePickerController.SourceType.camera;
imagePicker.allowsEditing = false
self.present(imagePicker, animated: true, completion: nil)
}
}
@IBAction func photolibraryaction(_ sender: UIButton) {
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerController.SourceType.photoLibrary) {
let imagepicker = UIImagePickerController()
imagepicker.delegate = self
imagepicker.sourceType = UIImagePickerController.SourceType.photoLibrary;
imagepicker.allowsEditing = true
self.present(imagepicker, animated: true, completion: nil)
}
}
}
swift swift4.2
edited Nov 21 '18 at 9:52
Govind Kumawat
715410
asked Nov 20 '18 at 21:47
pepijn Dikpepijn Dik
1
maybe a simple question. I am trying to make an app where you can draw straight lines: horizontal vertical and diagonal.
I am also trying to give measurements to the lines (don`t get this working yet..)
I have fixed that I can draw lines but not straight (like a pencil without ruler
can't find any documentation on the web to draw straight lines)
import UIKit
import Foundation
class tekengedeelte: UIViewController, UITextFieldDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
@IBOutlet weak var tekenview: UIView!
var path = UIBezierPath()
var startPoint = CGPoint()
var touchPoint = CGPoint()
var setSigImage: ((_ data: UIImage) -> ())?
var setcameraimage: ((_ data: UIImage) -> ())?
override func viewDidLoad() {
super.viewDidLoad()
tekenview.layer.shadowOpacity = 1
tekenview.layer.shadowRadius = 10
tekenview.layer.shadowOffset = CGSize(width: 1, height: 1)
tekenview.layer.shadowColor = UIColor.black.cgColor
//tekenview.layer.shadowPath = UIBezierPath(rect: tekenview.bounds).cgPath
tekenview.layer.shadowPath = CGPath(rect: tekenview.bounds, transform: nil)
tekenview.layer.shouldRasterize = true
tekenview.clipsToBounds = true
tekenview.isMultipleTouchEnabled = false
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
if let point = touch?.location(in: tekenview) {
startPoint = point
}
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
if let point = touch?.location(in: tekenview) {
touchPoint = point
}
path.move(to: startPoint)
path.addLine(to: touchPoint)
startPoint = touchPoint
draw()
}
func draw() {
let strokeLayer = CAShapeLayer()
strokeLayer.fillColor = UIColor.black.cgColor
strokeLayer.lineWidth = 5
strokeLayer.strokeColor = UIColor.black.cgColor
strokeLayer.path = path.cgPath
tekenview.layer.addSublayer(strokeLayer)
tekenview.setNeedsDisplay()
}
@IBAction func clearPressed(_ sender: UIButton) {
path.removeAllPoints()
tekenview.layer.sublayers = nil
tekenview.setNeedsDisplay()
}
@IBAction func setPressed(_ sender: UIButton) {
// Convert CanvasView to UIImage
let renderer = UIGraphicsImageRenderer(size: tekenview.bounds.size)
let image = renderer.image { ctx in
view.drawHierarchy(in: view.bounds, afterScreenUpdates: true)
}
// Send image back to onboarding screen
setSigImage?(image)
// Rotate device back to portrait mode
//let appDelegate = UIApplication.shared.delegate as! AppDelegate
//appDelegate.r = .portrait
// Close modal window
dismiss(animated: true)
}
//foto maken
@IBAction func camera(_ sender: UIButton) {
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerController.SourceType.camera){
let imagePicker = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = UIImagePickerController.SourceType.camera;
imagePicker.allowsEditing = false
self.present(imagePicker, animated: true, completion: nil)
}
}
@IBAction func photolibraryaction(_ sender: UIButton) {
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerController.SourceType.photoLibrary) {
let imagepicker = UIImagePickerController()
imagepicker.delegate = self
imagepicker.sourceType = UIImagePickerController.SourceType.photoLibrary;
imagepicker.allowsEditing = true
self.present(imagepicker, animated: true, completion: nil)
}
}
}
swift swift4.2
swift swift4.2
edited Nov 21 '18 at 9:52
Govind Kumawat
715410
asked Nov 20 '18 at 21:47
pepijn Dikpepijn Dik
1
edited Nov 21 '18 at 9:52
Govind Kumawat
715410
asked Nov 20 '18 at 21:47
pepijn Dikpepijn Dik
1
edited Nov 21 '18 at 9:52
Govind Kumawat
715410
edited Nov 21 '18 at 9:52
Govind Kumawat
715410
edited Nov 21 '18 at 9:52
Govind Kumawat
715410
715410
asked Nov 20 '18 at 21:47
pepijn Dikpepijn Dik
1
asked Nov 20 '18 at 21:47
pepijn Dikpepijn Dik
1
asked Nov 20 '18 at 21:47
pepijn Dikpepijn Dik
1
1
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
0
As Reinier Melian explained drawing straight line using core graphics. When the touch ended draw the save image using CGContext to show in UIImageView.
You need keep the current context until the line draw process has ended, after that you need keep the current image and clear the context, draw the saved image again, and draw the new line. When the touch ended is called clean the current context and save the current image, after that start the new line draw process again.
import UIKit
class ViewController2: UIViewController {
@IBOutlet weak var drawingPlace: UIImageView!
var startTouch : CGPoint?
var secondTouch : CGPoint?
var currentContext : CGContext?
var prevImage : UIImage?
override func viewDidLoad() {
super.viewDidLoad()
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
startTouch = touch?.location(in: drawingPlace)
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
for touch in touches{
secondTouch = touch.location(in: drawingPlace)
if(self.currentContext == nil){
UIGraphicsBeginImageContext(drawingPlace.frame.size)
self.currentContext = UIGraphicsGetCurrentContext()
}else{
self.currentContext?.clear(CGRect(x: 0, y: 0, width: drawingPlace.frame.width, height: drawingPlace.frame.height))
}
self.prevImage?.draw(in: self.drawingPlace.bounds)
let bezier = UIBezierPath()
bezier.move(to: startTouch!)
bezier.addLine(to: secondTouch!)
bezier.close()
UIColor.blue.set()
self.currentContext?.setLineWidth(4)
self.currentContext?.addPath(bezier.cgPath)
self.currentContext?.strokePath()
let img2 = self.currentContext?.makeImage()
drawingPlace.image = UIImage.init(cgImage: img2!)
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
self.currentContext = nil
self.prevImage = self.drawingPlace.image
}
}
answered Nov 21 '18 at 13:31
Govind KumawatGovind Kumawat
715410
add a comment |
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1 Answer
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1 Answer
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As Reinier Melian explained drawing straight line using core graphics. When the touch ended draw the save image using CGContext to show in UIImageView.
You need keep the current context until the line draw process has ended, after that you need keep the current image and clear the context, draw the saved image again, and draw the new line. When the touch ended is called clean the current context and save the current image, after that start the new line draw process again.
import UIKit
class ViewController2: UIViewController {
@IBOutlet weak var drawingPlace: UIImageView!
var startTouch : CGPoint?
var secondTouch : CGPoint?
var currentContext : CGContext?
var prevImage : UIImage?
override func viewDidLoad() {
super.viewDidLoad()
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
startTouch = touch?.location(in: drawingPlace)
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
for touch in touches{
secondTouch = touch.location(in: drawingPlace)
if(self.currentContext == nil){
UIGraphicsBeginImageContext(drawingPlace.frame.size)
self.currentContext = UIGraphicsGetCurrentContext()
}else{
self.currentContext?.clear(CGRect(x: 0, y: 0, width: drawingPlace.frame.width, height: drawingPlace.frame.height))
}
self.prevImage?.draw(in: self.drawingPlace.bounds)
let bezier = UIBezierPath()
bezier.move(to: startTouch!)
bezier.addLine(to: secondTouch!)
bezier.close()
UIColor.blue.set()
self.currentContext?.setLineWidth(4)
self.currentContext?.addPath(bezier.cgPath)
self.currentContext?.strokePath()
let img2 = self.currentContext?.makeImage()
drawingPlace.image = UIImage.init(cgImage: img2!)
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
self.currentContext = nil
self.prevImage = self.drawingPlace.image
}
}
answered Nov 21 '18 at 13:31
Govind KumawatGovind Kumawat
715410
add a comment |
0
As Reinier Melian explained drawing straight line using core graphics. When the touch ended draw the save image using CGContext to show in UIImageView.
You need keep the current context until the line draw process has ended, after that you need keep the current image and clear the context, draw the saved image again, and draw the new line. When the touch ended is called clean the current context and save the current image, after that start the new line draw process again.
import UIKit
class ViewController2: UIViewController {
@IBOutlet weak var drawingPlace: UIImageView!
var startTouch : CGPoint?
var secondTouch : CGPoint?
var currentContext : CGContext?
var prevImage : UIImage?
override func viewDidLoad() {
super.viewDidLoad()
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
startTouch = touch?.location(in: drawingPlace)
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
for touch in touches{
secondTouch = touch.location(in: drawingPlace)
if(self.currentContext == nil){
UIGraphicsBeginImageContext(drawingPlace.frame.size)
self.currentContext = UIGraphicsGetCurrentContext()
}else{
self.currentContext?.clear(CGRect(x: 0, y: 0, width: drawingPlace.frame.width, height: drawingPlace.frame.height))
}
self.prevImage?.draw(in: self.drawingPlace.bounds)
let bezier = UIBezierPath()
bezier.move(to: startTouch!)
bezier.addLine(to: secondTouch!)
bezier.close()
UIColor.blue.set()
self.currentContext?.setLineWidth(4)
self.currentContext?.addPath(bezier.cgPath)
self.currentContext?.strokePath()
let img2 = self.currentContext?.makeImage()
drawingPlace.image = UIImage.init(cgImage: img2!)
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
self.currentContext = nil
self.prevImage = self.drawingPlace.image
}
}
answered Nov 21 '18 at 13:31
Govind KumawatGovind Kumawat
715410
add a comment |
0
0
0
As Reinier Melian explained drawing straight line using core graphics. When the touch ended draw the save image using CGContext to show in UIImageView.
You need keep the current context until the line draw process has ended, after that you need keep the current image and clear the context, draw the saved image again, and draw the new line. When the touch ended is called clean the current context and save the current image, after that start the new line draw process again.
import UIKit
class ViewController2: UIViewController {
@IBOutlet weak var drawingPlace: UIImageView!
var startTouch : CGPoint?
var secondTouch : CGPoint?
var currentContext : CGContext?
var prevImage : UIImage?
override func viewDidLoad() {
super.viewDidLoad()
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
startTouch = touch?.location(in: drawingPlace)
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
for touch in touches{
secondTouch = touch.location(in: drawingPlace)
if(self.currentContext == nil){
UIGraphicsBeginImageContext(drawingPlace.frame.size)
self.currentContext = UIGraphicsGetCurrentContext()
}else{
self.currentContext?.clear(CGRect(x: 0, y: 0, width: drawingPlace.frame.width, height: drawingPlace.frame.height))
}
self.prevImage?.draw(in: self.drawingPlace.bounds)
let bezier = UIBezierPath()
bezier.move(to: startTouch!)
bezier.addLine(to: secondTouch!)
bezier.close()
UIColor.blue.set()
self.currentContext?.setLineWidth(4)
self.currentContext?.addPath(bezier.cgPath)
self.currentContext?.strokePath()
let img2 = self.currentContext?.makeImage()
drawingPlace.image = UIImage.init(cgImage: img2!)
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
self.currentContext = nil
self.prevImage = self.drawingPlace.image
}
}
answered Nov 21 '18 at 13:31
Govind KumawatGovind Kumawat
715410
As Reinier Melian explained drawing straight line using core graphics. When the touch ended draw the save image using CGContext to show in UIImageView.
You need keep the current context until the line draw process has ended, after that you need keep the current image and clear the context, draw the saved image again, and draw the new line. When the touch ended is called clean the current context and save the current image, after that start the new line draw process again.
import UIKit
class ViewController2: UIViewController {
@IBOutlet weak var drawingPlace: UIImageView!
var startTouch : CGPoint?
var secondTouch : CGPoint?
var currentContext : CGContext?
var prevImage : UIImage?
override func viewDidLoad() {
super.viewDidLoad()
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch = touches.first
startTouch = touch?.location(in: drawingPlace)
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
for touch in touches{
secondTouch = touch.location(in: drawingPlace)
if(self.currentContext == nil){
UIGraphicsBeginImageContext(drawingPlace.frame.size)
self.currentContext = UIGraphicsGetCurrentContext()
}else{
self.currentContext?.clear(CGRect(x: 0, y: 0, width: drawingPlace.frame.width, height: drawingPlace.frame.height))
}
self.prevImage?.draw(in: self.drawingPlace.bounds)
let bezier = UIBezierPath()
bezier.move(to: startTouch!)
bezier.addLine(to: secondTouch!)
bezier.close()
UIColor.blue.set()
self.currentContext?.setLineWidth(4)
self.currentContext?.addPath(bezier.cgPath)
self.currentContext?.strokePath()
let img2 = self.currentContext?.makeImage()
drawingPlace.image = UIImage.init(cgImage: img2!)
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
self.currentContext = nil
self.prevImage = self.drawingPlace.image
}
}
answered Nov 21 '18 at 13:31
Govind KumawatGovind Kumawat
715410
answered Nov 21 '18 at 13:31
Govind KumawatGovind Kumawat
715410
answered Nov 21 '18 at 13:31
Govind KumawatGovind Kumawat
715410
answered Nov 21 '18 at 13:31
Govind KumawatGovind Kumawat
715410
715410
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