Swift newbie here.
I've been having trouble with a task that should be trivial. All I want to do is get the x,y coordinates of the mouse cursor on-demand. I would prefer not to wait for a mouse movement event to fire before I can grab the pointer's coords.
Would appreciate any help!
You should take a look at NSEvent method mouseLocation
edit/update: Xcode 11 • Swift 5.1
If you would like to monitor events on any window when your app is active, you can add a LocalMonitorForEvents matching mouseMoved mask and if it is not active a GlobalMonitorForEvents. Note that you need set to your window property acceptsMouseMovedEvents to true
import Cocoa
class ViewController: NSViewController {
lazy var window: NSWindow = self.view.window!
var mouseLocation: NSPoint { NSEvent.mouseLocation }
var location: NSPoint { window.mouseLocationOutsideOfEventStream }
override func viewDidLoad() {
super.viewDidLoad()
NSEvent.addLocalMonitorForEvents(matching: [.mouseMoved]) {
print("mouseLocation:", String(format: "%.1f, %.1f", self.mouseLocation.x, self.mouseLocation.y))
print("windowLocation:", String(format: "%.1f, %.1f", self.location.x, self.location.y))
return $0
}
NSEvent.addGlobalMonitorForEvents(matching: [.mouseMoved]) { _ in
print(String(format: "%.0f, %.0f", self.mouseLocation.x, self.mouseLocation.y))
}
}
override func viewWillAppear() {
super.viewWillAppear()
window.acceptsMouseMovedEvents = true
}
}
Sample project
You can get the current mouse location in this way:
Declare this in your view controller class:
var mouseLocation: NSPoint? { self.view.window?.mouseLocationOutsideOfEventStream }
Then, you can get the current mouse location and convert in your desired view coordinates:
if let currentMouseLocation = self.mouseLocation{
let pointInTargetView = self.**targetView**.convert(currentMouseLocation, from: self.view)
}
Related
I have been experimenting with mouse clicks. I am ok with left mouse clicks getting raw values etc etc. I now want to add right mouse clicks. I have setup a basic example. What i would like to achieve if there is one mouse right click it performs one function, and if there is two mouse right clicks it performs a different function. The problem is if you do two mouse clicks it obviously cannot differentiate between the two and so fire the one mouse click function before performing the second mouse function.
I was thinking of maybe using a timer of some sort to record the number of click. But i end up going round in circles as i just seem to start the timers over and over. I'm hoping some one might help. thanks for reading here is the code.
Xcode 8 Swift 3 Mac OSX Sierra NOT IOS.. NOT IOS
import Cocoa
class MainWindowController: NSWindowController {
#IBOutlet weak var MyView: NSView!
override func windowDidLoad() {
super.windowDidLoad()
//Initialize mouse for Right Click numberOfClicksRequired = 1
let recogRightClick1 = NSClickGestureRecognizer(target: self, action: #selector(oneMouseClick))
recogRightClick1.buttonMask = 0x2
recogRightClick1.numberOfClicksRequired = 1
MyView.addGestureRecognizer(recogRightClick1)
//Initialize mouse for Right ClicknumberOfClicksRequired = 2
let recogRightClick2 = NSClickGestureRecognizer(target: self, action: #selector(twoMouseClick(myrec:myRightClick:)))
recogRightClick2.buttonMask = 0x2
recogRightClick2.numberOfClicksRequired = 2
MyView.addGestureRecognizer(recogRightClick2)
}//EO Overide
func oneMouseClick(myrec: NSPanGestureRecognizer,myRightClick:NSClickGestureRecognizer){
let rightClick = myRightClick.state.rawValue
print("oneMouseClick",rightClick)
}
func twoMouseClick(myrec: NSPanGestureRecognizer,myRightClick:NSClickGestureRecognizer){
let rightClick = myRightClick.state.rawValue
print("twoMouseClick",rightClick)
}
}//EnD oF thE wORld
UPDATE
I have re generated the code following the advice given. Now the code reflects more of what i wanted to do. My only problem is that I would like all the mouse operations to be triggered only inside 'myView' rather than within the main window. I thought it might have something to do with first responder but that doesn't seem to work. Again any thought would be appreciated. Please excuse any bad code i'm self taught.
Xcode 8 Swift 3 Mac OSX Sierra NOT IOS.. NOT IOS
import Cocoa
class MainWindowController: NSWindowController {
#IBOutlet weak var myView: NSView!
var mouseX:CGFloat = 0
var mouseY:CGFloat = 0
override func windowDidLoad() {
myView.window?.becomeFirstResponder()
myView.window?.acceptsMouseMovedEvents = true
super.windowDidLoad()
myView.wantsLayer = true
myView.layer?.backgroundColor = CGColor(red: 0.05, green: 0.57, blue: 0.80, alpha: 0.6)
NSEvent.addLocalMonitorForEvents(matching:.leftMouseDown){
self.mouseEventFunction(data: 1)
return $0
}
NSEvent.addLocalMonitorForEvents(matching:.leftMouseUp){
self.mouseEventFunction(data:2)
return $0
}
NSEvent.addLocalMonitorForEvents(matching:.rightMouseDown){
self.mouseEventFunction(data: 3)
return $0
}
NSEvent.addLocalMonitorForEvents(matching:.rightMouseUp){
self.mouseEventFunction(data: 4)
return $0
}
NSEvent.addLocalMonitorForEvents(matching:.mouseMoved) {
self.mouseX = NSEvent.mouseLocation().x
self.mouseY = NSEvent.mouseLocation().y
return $0 }
}//EO Overide
func mouseEventFunction (data: Int){
switch data{
case 1 :
print("LeftMouseDown")
case 2 :
print("LeftMouseUp")
case 3 :
print("RightMouseDown")
case 3 :
print("RightMouseUP")
default: break
}
if data == 1 {print("mouseX",mouseX,"mouseY",mouseY)}
}//eo mouseEvent
}//EnD oF thE wORld
UPDATE 2
I have now updated subClassing the view controller, so the mouse clicks are now only working in myView. I'm still having problems with 'func mouseDragged' What i need to achieve is the bottom left of my view is x = 0 and Y = 0. I had a try with converting but thats not working. hoping someone might guide me. thanks for reading here is the updated code.
Xcode 8 Swift 3 Mac OSX Sierra NOT IOS.. NOT IOS
import Cocoa
class MainWindowController: NSWindowController {
#IBOutlet weak var myView: NSView!
override func windowDidLoad() {
myView.window?.becomeFirstResponder()
myView.window?.acceptsMouseMovedEvents = true
window?.contentView?.addSubview(myView)
super.windowDidLoad()
}//EO Overide
}//EnD oF thE wORld
class testView: NSView {
override func draw(_ dirtyRect: NSRect) {
let backgroundColor = NSColor.lightGray
backgroundColor.set()
NSBezierPath.fill(bounds)
}
override func mouseDragged(with theEvent: NSEvent) {
let myLocationInWindow = theEvent.locationInWindow
let location = convert(myLocationInWindow, to: self)
Swift.print("myLocationInWindow",myLocationInWindow,"location",location)
}
override func mouseDown(with theEvent: NSEvent) {
Swift.print("mouseDown")
}
override func mouseUp(with theEvent: NSEvent) {
Swift.print("mouseUp clickCount: \(theEvent.clickCount)")
}
}//eo testView
To define mouse inside view you use
let myLocationInWindow = theEvent.locationInWindow
let location = convert(myLocationInWindow, from: nil)
where nil is the window
here is the final code
import Cocoa
class MainWindowController: NSWindowController {
#IBOutlet weak var myView: NSView!
override func windowDidLoad() {
super.windowDidLoad()
}//EO Overide
}//EnD oF thE wORld
class testView: NSView {
override func draw(_ dirtyRect: NSRect) {
let backgroundColor = NSColor.lightGray
backgroundColor.set()
NSBezierPath.fill(bounds)
}
override func mouseDragged(with theEvent: NSEvent) {
let myLocationInWindow = theEvent.locationInWindow
let location = convert(myLocationInWindow, from: nil)
Swift.print("location",location)
}
override func mouseDown(with theEvent: NSEvent) {
Swift.print("mouseDown")
}
override func mouseUp(with theEvent: NSEvent) {
Swift.print("mouseUp clickCount: \(theEvent.clickCount)")
}
}//eo testView
I am having trouble getting custom SKSpriteNode buttons to work with the xCode level editor on devices with 3d Touch.
I have a button subclass which is mostly based on the DemoBots sample from apple.
The basic code would be this
enum ButtonIdentifier: String {
case playButton
case pauseButton
}
/// Button responder delegate
protocol ButtonDelegate: class {
func pressed(button button: ButtonNode)
}
class ButtonNode: SKSpriteNode {
public weak var delegate: ButtonDelegate? {
return scene as? ButtonDelegate
}
var isHighlighted = false {
didSet {
// running skactions to colorise buttons and animate
}
}
var identifier: ButtonIdentifier!
/// Code init (when button is created in code)
/// e.g let playButton = ButtonNode(imageNamed: "ButtonImage", identifier: playButton)
init(imageNamed: String, identifier: ButtonIdentifier) {
self.identifier = identifier
let texture = SKTexture(imageNamed: imageNamed)
super.init(texture: texture, color: SKColor.clearColor(), size: texture.size())
name = identifier.rawValue
setup()
}
/// Level editor init (when button is created in level editor)
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
// Ensure that the node has a supported button identifier as its name.
guard let nodeName = name, identifier = ButtonIdentifier(rawValue: nodeName) else {
fatalError("Unsupported button name found.")
}
self.identifier = identifier
setup()
}
private func setup() {
// zPosition
zPosition = 200
// Enable user interaction on the button node to detect tap and click events.
userInteractionEnabled = true
}
#if os(iOS)
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
super.touchesBegan(touches, withEvent: event)
isHighlighted = true
}
override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
super.touchesEnded(touches, withEvent: event)
guard let scene = scene else { return }
for touch in touches {
let location = touch.locationInNode(scene)
let node = scene.nodeAtPoint(location)
if node === self || node.inParentHierarchy(self) {
runPressedAction()
} else {
isHighlighted = false
}
}
}
override func touchesCancelled(touches: Set<UITouch>?, withEvent event: UIEvent?) {
super.touchesCancelled(touches, withEvent: event)
isHighlighted = false
}
#endif
// MARK: - Pressed Action
private func runPressedAction() {
// SKAction that runs a press animation
delegate?.pressed(button: self)
}
}
If i create the button via the xCode level editor everything is working fine in the simulator or on my iPhone 6, however when using test flight my friend with a 6s Plus gets no touch input on the buttons, he cannot press them.
If I create the button all in code everything works, even on 3d touch devices.
Why is it not working with buttons from the level editor on 3d touch devices? I have been trying to look at apples demo bots sample to see if I missed some setting or something, but I cannot figure it out. (Demo bots buttons do work on my friends iPhone 6s plus)
I know that on 3d touch devices touchesMoved method gets called even though there are no changes in the x/y coordinates. However I don't think this causes my issues because when creating buttons in code everything is working as expected.
Is there some setting in the Xcode level editor I am missing to allow touches on 3d touch devices?
After days of frustration it turned out it was a iOS 9 bug. My friend was on iOS 9.2.x and after he updated to the latest iOS 9.3.x version everything is working, no code changes where required at all.
I am new to Mac OSX and with Apple promoting the fact that the bodies of code are becoming similar decided to tell the folk I am writing code for we should be able to do a Mac OSX version. iPhone and iPad versions are all good and about to release second version so no issues there.
So I am subclassing NSWindowController to get access to the Toolbar and worked out how to remove and add items on the toolbar, but for the life of me I can not get one NSViewController (firstViewController) to dismiss and bring up the second NSViewController (secondViewController) in the same NSWindowController.
So the 2 issues are that
1. I want to be able to performSegueWithIdentifier from the first NSViewController in code and
2. bring up the second NSViewController by replacing the first NSViewController in the same NSWindowController.
If I add a button to the firstViewController and put a segue to the secondViewController then when I select the button the secondViewController comes up just fine but in a seperate window not the same NSWindowController that I want it to and the firstViewController does not get replaced but stays in the NSWindowController.
So I know the segue idea will work but its not working in code and when I do insert the segue from a button it works but into a seperate NSViewController that is not part of the NSWindowController.
I am trying to find some programming guide from Apple on the issue but no luck so far.
Here is an overview from my Storyboard:
Here is my NSWindowController subclassed and the func loginToMe2Team is trigger from the NSToolBar and its working just find as the print statements show up on the console.
import Cocoa
class me2teamWindowsController: NSWindowController {
#IBOutlet var mySignUp : NSToolbarItem!
#IBOutlet var myToolbar : NSToolbar!
let controller = ViewController()
override func windowDidLoad() {
super.windowDidLoad()
print("window loaded")
}
override func windowWillLoad() {
print("window will load")
}
#IBAction func logInToMe2Team(sender: AnyObject){
controller.LogIn() //THIS IS THE FUNC I AM TESTING WITH
}
#IBAction func signUpToMe2Team(sender: AnyObject){
controller.signUp()
}
Here is my NSViewController subclassed with the func LogIn. Its getting selected just fine but the performSegueWithIdentifier is not. And I did cut and past the Identifier to make absolutely sure it was the same.
import Cocoa
import WebKit
class ViewController: NSViewController {
#IBOutlet weak var theWebPage: WebView!
#IBOutlet weak var progressIndicator: NSProgressIndicator!
override func viewDidLoad() {
super.viewDidLoad()
let urlString = "https://thewebpage.com.au"
self.theWebPage.mainFrame.loadRequest(NSURLRequest(URL: NSURL(string: urlString)!))
}
override func viewDidAppear() {
}
func LogIn() {
print("I logged in")
self.performSegueWithIdentifier("goToTeamPage", sender: self)
//THIS IS THE BIT THATS NOT WORKING
}
func signUp() {
print("I have to sign up now")
}
override var representedObject: AnyObject? {
didSet {
}
}
func webView(sender: WebView!, didStartProvisionalLoadForFrame frame: WebFrame!)
{
self.progressIndicator.startAnimation(self)
}
func webView(sender: WebView!, didFinishLoadForFrame frame: WebFrame!)
{
self.progressIndicator.stopAnimation(self)
}
}
You need to use a custom segue class (or possibly NSTabViewController if it’s enough for your needs). Set the segue’s type to Custom, with your class name specified:
…and implement it. With no animation, it’s simple:
class ReplaceSegue: NSStoryboardSegue {
override func perform() {
if let src = self.sourceController as? NSViewController,
let dest = self.destinationController as? NSViewController,
let window = src.view.window {
// this updates the content and adjusts window size
window.contentViewController = dest
}
}
}
In my case, I was using a sheet and wanted to transition to a different sheet with a different size, so I needed to do more:
class ReplaceSheetSegue: NSStoryboardSegue {
override func perform() {
if let src = self.sourceController as? NSViewController,
let dest = self.destinationController as? NSViewController,
let window = src.view.window {
// calculate new frame:
var rect = window.frameRectForContentRect(dest.view.frame)
rect.origin.x += (src.view.frame.width - dest.view.frame.width) / 2
rect.origin.y += src.view.frame.height - dest.view.frame.height
// don’t shrink visible content, prevent minsize from intervening:
window.contentViewController = nil
// animate resizing (TODO: crossover blending):
window.setFrame(window.convertRectToScreen(rect), display: true, animate: true)
// set new controller
window.contentViewController = dest
}
}
}
I have a node in the middle of my screen and currently have this code that moves the node to the left with each tap on the left side of the screen and to the right with each tap on the right side of the screen. I want to change this to a long press instead of a tap. How would I do this? Thanks! This is the code for the tap.
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
var touch: UITouch = touches.anyObject() as UITouch
var location = touch.locationInNode(self)
var node = self.nodeAtPoint(location)
var speedOfTouch:CGFloat = 30
//moves to the left and right by touch and plays sound effect by touch.
for touch: AnyObject in touches {
let location = touch.locationInNode(self)
if location.x < CGRectGetMidX(self.frame) {
hero.position.x -= speedOfTouch
AudioPlayer.play()
} else {
hero.position.x += speedOfTouch
AudioPlayer.play()
}
This should be very straightforward. Initialize a UILongPressGestureRecognizer in your view's initializer. You can optionally adjust the minimumPressDuration and allowableMovement properties if desired before adding the gesture recognizer to the view.
override init(frame aRect: CGRect) {
// ...
// Create the long press gesture recognizer, and configure it
// to call a method named viewLongPressed: on self
let longPress = UILongPressGestureRecognizer(target: self, action: "viewLongPressed:")
// Optionally configure it - see the documentation for explanations
// longPress.minimumPressDuration = 1.0
// longPress.allowableMovement = 15
// Add the gesture recognizer to this view (self)
addGestureRecognizer(longPress)
// ...
}
Then just implement the callback method:
func viewLongPressed(gestureRecognizer: UIGestureRecognizer) {
// Handle the long press event by examining the passed in
// gesture recognizer
}
I read the document Synchronizing Scroll Views, and did exactly as the document, but there is an isssue.
I want to synchronize a NSTableView and a NSTextView. first let NSTableView monitor NSTextView, and everything is ok when I scroll the TextView, but when I try to scroll TableView, I found that the TableView will jump to another place(maybe backward several rows) at first, then continue to scroll from that place.
This issue still exists even after I let TextView monitor TableView.
anyone know what's the problem? can't I synchronize a TableView and a TextView?
Edited:
OK, now I found that the TableView will go back to the place since last scrolling. for example, TableView's top row is 10th row, then I scroll TextView, now TableView's top row is 20th row, and if I scroll TableView again, the TableView will go back to 10th row first, then start to scroll.
I just ran into this exact problem while troubleshooting a very similar situation (on Lion). I noticed that this only occurs when the scrollers are hidden -- but I verified that they still exist in the nib, and are still instantiated correctly.
I even made sure to call -[NSScrollView reflectScrolledClipView:], but it didn't make a difference. It really seems like this is a bug in NSScrollView.
Anyway, I was able to work around the issue by creating a custom scroller class. All I had to do was override the following class methods:
+ (BOOL)isCompatibleWithOverlayScrollers
{
// Let this scroller sit on top of the content view, rather than next to it.
return YES;
}
- (void)setHidden:(BOOL)flag
{
// Ugly hack: make sure we are always hidden.
[super setHidden:YES];
}
Then, I allowed the scrollers to be "visible" in Interface Builder. Since they hide themselves, however, they do no appear onscreen and they can't be clicked by the user. It's surprising that the IB setting and the hidden property are not equivalent, but it seems clear from the behavior that they are not.
This isn't the best solution, but it's the simplest workaround I've come up with (so far).
I had a quite similar problem.
I have 3 scrollviews to synchronize.
One that is a header that only scrolls horizontally.
One that is a side bar that only scrolls vertically.
One that is a content area below the header and to the right of the side bar.
The header and side bar should move with the content area.
The content area should move with the header or the side bar if either is scrolled.
Horizontal scrolling was never a problem.
Vertical scrolling was always causing the two views to scroll opposite directions.
The odd resolution I came to was to create a clipView subclass (which I already did, as you pretty much always need to if you want anything nice that doesn't come out of the box.)
In the clipView subclass, I add a property BOOL isInverted and in the override of isFlipped I return self.isInverted.
The weird thing is that these BOOL values for flippedness are set and match in all 3 views from the beginning.
It seems that scrolling machinery is indeed buggy.
My workaround that I stumbled upon was to sandwich the scroll synching code between calls to set both the side bar and content view unflipped and then update any vertical scrolling, then set both flipped again.
Must be some aging code in the scrolling machinery trying to support inverted scrolling...
These are the methods called by the NSNotificationCenter addObserver methods to observe the NSViewBoundsDidChangeNotification for the clipViews.
- (void)synchWithVerticalControlClipView:(NSNotification *)aNotification
{
NSPoint mouseInWindow = self.view.window.currentEvent.locationInWindow;
NSPoint converted = [self.verticalControl.enclosingScrollView convertPoint:mouseInWindow fromView:nil];
if (!NSPointInRect(converted, self.verticalControl.enclosingScrollView.bounds)) {
return;
}
[self.contentGridClipView setIsInverted:NO];
[self.verticalControlClipView setIsInverted:NO];
// ONLY update the contentGrid view.
NSLog(#"%#", NSStringFromSelector(_cmd));
NSPoint changedBoundsOrigin = self.verticalControlClipView.documentVisibleRect.origin;
NSPoint currentOffset = self.contentGridClipView.bounds.origin;
NSPoint newOffset = currentOffset;
newOffset.y = changedBoundsOrigin.y;
NSLog(#"\n changedBoundsOrigin=%#\n currentOffset=%#\n newOffset=%#", NSStringFromPoint(changedBoundsOrigin), NSStringFromPoint(currentOffset), NSStringFromPoint(newOffset));
[self.contentGridClipView scrollToPoint:newOffset];
[self.contentGridClipView.enclosingScrollView reflectScrolledClipView:self.contentGridClipView];
[self.contentGridClipView setIsInverted:YES];
[self.verticalControlClipView setIsInverted:YES];
}
- (void)synchWithContentGridClipView:(NSNotification *)aNotification
{
NSPoint mouseInWindow = self.view.window.currentEvent.locationInWindow;
NSPoint converted = [self.contentGridView.enclosingScrollView convertPoint:mouseInWindow fromView:nil];
if (!NSPointInRect(converted, self.contentGridView.enclosingScrollView.bounds)) {
return;
}
[self.contentGridClipView setIsInverted:NO];
[self.verticalControlClipView setIsInverted:NO];
// Update BOTH the control views.
NSLog(#"%#", NSStringFromSelector(_cmd));
NSPoint changedBoundsOrigin = self.contentGridClipView.documentVisibleRect.origin;
NSPoint currentHOffset = self.horizontalControlClipView.documentVisibleRect.origin;
NSPoint currentVOffset = self.verticalControlClipView.documentVisibleRect.origin;
NSPoint newHOffset, newVOffset;
newHOffset = currentHOffset;
newVOffset = currentVOffset;
newHOffset.x = changedBoundsOrigin.x;
newVOffset.y = changedBoundsOrigin.y;
[self.horizontalControlClipView scrollToPoint:newHOffset];
[self.verticalControlClipView scrollToPoint:newVOffset];
[self.horizontalControlClipView.enclosingScrollView reflectScrolledClipView:self.horizontalControlClipView];
[self.verticalControlClipView.enclosingScrollView reflectScrolledClipView:self.verticalControlClipView];
[self.contentGridClipView setIsInverted:YES];
[self.verticalControlClipView setIsInverted:YES];
}
This works 99% of the time, with only occasional jitter.
Horizontal scroll synch has no problems.
Swift 4 version which uses document view in auto-layout environment.
Based on Apple article Synchronizing Scroll Views with the difference that NSView.boundsDidChangeNotification temporary ignored on clip view when synchronising to other scroll view.
To hide vertical scroller reusable type InvisibleScroller is used.
File SynchronedScrollViewController.swift – View controllers with two scroll views.
class SynchronedScrollViewController: ViewController {
private lazy var leftView = TestView().autolayoutView()
private lazy var rightView = TestView().autolayoutView()
private lazy var leftScrollView = ScrollView(horizontallyScrolledDocumentView: leftView).autolayoutView()
private lazy var rightScrollView = ScrollView(horizontallyScrolledDocumentView: rightView).autolayoutView()
override func setupUI() {
view.addSubviews(leftScrollView, rightScrollView)
leftView.backgroundColor = .red
rightView.backgroundColor = .blue
contentView.backgroundColor = .green
leftScrollView.verticalScroller = InvisibleScroller()
leftView.setIntrinsicContentSize(CGSize(intrinsicHeight: 720)) // Some fake height
rightView.setIntrinsicContentSize(CGSize(intrinsicHeight: 720)) // Some fake height
}
override func setupHandlers() {
(leftScrollView.contentView as? ClipView)?.onBoundsDidChange = { [weak self] in
print("\(Date().timeIntervalSinceReferenceDate) : Left scroll view changed")
self?.syncScrollViews(origin: $0)
}
(rightScrollView.contentView as? ClipView)?.onBoundsDidChange = { [weak self] in
print("\(Date().timeIntervalSinceReferenceDate) : Right scroll view changed.")
self?.syncScrollViews(origin: $0)
}
}
override func setupLayout() {
LayoutConstraint.pin(to: .vertically, leftScrollView, rightScrollView).activate()
LayoutConstraint.withFormat("|[*(==40)]-[*]|", leftScrollView, rightScrollView).activate()
}
private func syncScrollViews(origin: NSClipView) {
// See also:
// https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/NSScrollViewGuide/Articles/SynchroScroll.html
let changedBoundsOrigin = origin.documentVisibleRect.origin
let targetScrollView = leftScrollView.contentView == origin ? rightScrollView : leftScrollView
let curOffset = targetScrollView.contentView.bounds.origin
var newOffset = curOffset
newOffset.y = changedBoundsOrigin.y
if curOffset != changedBoundsOrigin {
(targetScrollView.contentView as? ClipView)?.scroll(newOffset, shouldNotifyBoundsChange: false)
targetScrollView.reflectScrolledClipView(targetScrollView.contentView)
}
}
}
File: TestView.swift – Test view. Draws line every 20 points.
class TestView: View {
override init() {
super.init()
setIsFlipped(true)
}
override func setupLayout() {
needsDisplay = true
}
required init?(coder decoder: NSCoder) {
fatalError()
}
override func draw(_ dirtyRect: NSRect) {
super.draw(dirtyRect)
guard let context = NSGraphicsContext.current else {
return
}
context.saveGraphicsState()
let cgContext = context.cgContext
cgContext.setStrokeColor(NSColor.white.cgColor)
for x in stride(from: CGFloat(20), through: bounds.height, by: 20) {
cgContext.addLines(between: [CGPoint(x: 0, y: x), CGPoint(x: bounds.width, y: x)])
NSString(string: "\(Int(x))").draw(at: CGPoint(x: 0, y: x), withAttributes: nil)
}
cgContext.strokePath()
context.restoreGraphicsState()
}
}
File: NSScrollView.swift - Reusable extension.
extension NSScrollView {
public convenience init(documentView view: NSView) {
let frame = CGRect(dimension: 10) // Some dummy non zero value
self.init(frame: frame)
let clipView = ClipView(frame: frame)
clipView.documentView = view
clipView.autoresizingMask = [.height, .width]
contentView = clipView
view.frame = frame
view.translatesAutoresizingMaskIntoConstraints = true
view.autoresizingMask = [.width, .height]
}
public convenience init(horizontallyScrolledDocumentView view: NSView) {
self.init(documentView: view)
contentView.setIsFlipped(true)
view.translatesAutoresizingMaskIntoConstraints = false
LayoutConstraint.pin(in: contentView, to: .horizontally, view).activate()
view.topAnchor.constraint(equalTo: contentView.topAnchor).activate()
hasVerticalScroller = true // Without this scroll might not work properly. Seems Apple bug.
}
}
File: InvisibleScroller.swift - Reusable invisible scroller.
// Disabling scroll view indicators.
// See: https://stackoverflow.com/questions/9364953/hide-scrollers-while-leaving-scrolling-itself-enabled-in-nsscrollview
public class InvisibleScroller: Scroller {
public override class var isCompatibleWithOverlayScrollers: Bool {
return true
}
public override class func scrollerWidth(for controlSize: NSControl.ControlSize, scrollerStyle: NSScroller.Style) -> CGFloat {
return CGFloat.leastNormalMagnitude // Dimension of scroller is equal to `FLT_MIN`
}
public override func setupUI() {
// Below assignments not really needed, but why not.
scrollerStyle = .overlay
alphaValue = 0
}
}
File: ClipView.swift - Customized subclass of NSClipView.
open class ClipView: NSClipView {
public var onBoundsDidChange: ((NSClipView) -> Void)? {
didSet {
setupBoundsChangeObserver()
}
}
private var boundsChangeObserver: NotificationObserver?
private var mIsFlipped: Bool?
open override var isFlipped: Bool {
return mIsFlipped ?? super.isFlipped
}
// MARK: -
public func setIsFlipped(_ value: Bool?) {
mIsFlipped = value
}
open func scroll(_ point: NSPoint, shouldNotifyBoundsChange: Bool) {
if shouldNotifyBoundsChange {
scroll(to: point)
} else {
boundsChangeObserver?.isActive = false
scroll(to: point)
boundsChangeObserver?.isActive = true
}
}
// MARK: - Private
private func setupBoundsChangeObserver() {
postsBoundsChangedNotifications = onBoundsDidChange != nil
boundsChangeObserver = nil
if postsBoundsChangedNotifications {
boundsChangeObserver = NotificationObserver(name: NSView.boundsDidChangeNotification, object: self) { [weak self] _ in
guard let this = self else { return }
self?.onBoundsDidChange?(this)
}
}
}
}
File: NotificationObserver.swift – Reusable Notification observer.
public class NotificationObserver: NSObject {
public typealias Handler = ((Foundation.Notification) -> Void)
private var notificationObserver: NSObjectProtocol!
private let notificationObject: Any?
public var handler: Handler?
public var isActive: Bool = true
public private(set) var notificationName: NSNotification.Name
public init(name: NSNotification.Name, object: Any? = nil, queue: OperationQueue = .main, handler: Handler? = nil) {
notificationName = name
notificationObject = object
self.handler = handler
super.init()
notificationObserver = NotificationCenter.default.addObserver(forName: name, object: object, queue: queue) { [weak self] in
guard let this = self else { return }
if this.isActive {
self?.handler?($0)
}
}
}
deinit {
NotificationCenter.default.removeObserver(notificationObserver, name: notificationName, object: notificationObject)
}
}
Result: