I have a UIView located a UIScrollView on it.
let curtainView = UIScrollView ()
curtainView.snp.makeConstraints {make in
make.edges.equalToSuperview ()
}
And also UIView.
let someView = UIView ()
someView.snp.makeConstraints {make in
make.top.equalToSuperview (). offset (10)
make.leading.trailing.equalToSuperview (). inset (10)
}
Objective: Set contentInset for UIScrollView depending on UIView visibility. UIView's visibility changes through RxSwift.
I am doing the following
override func layoutSubviews () {
super.layoutSubviews ()
curtainView.contentInset.top = someView.isHidden? self.frame.minY: someView.frame.maxY
}
The layoutSubviews method is called multiple times:
1.curtainView.contentInset.top == 0
2.curtainView.contentInset.top == 0
3.curtainView.contentInset.top == 30
However, visually the contentInset of someView remains unchanged. Only after the swipe does the curtain set the correct indents.
I do not have permission to add images, please see them on a third-party resource: https://youtu.be/LecHmLd9HP4
Related
I use storyboard to design my view-based NSTableView and its subviews with auto layouts. It is working fine and behaves as expected.
In my NSTableCellView, I have multiples NSTextField. I wish to programmatically change the frame in one of them. So I tried something like this.
dataSource = NSTableViewDiffableDataSource<Section, Item>(tableView: someTableView, cellProvider: { tableView, tableColumn, row, item -> NSView in
guard let tableCellView = tableView.makeView(withIdentifier: .someTableCellView, owner: self) as? SomeTableCellView else {
fatalError()
}
tableCellView.randomTextField.stringValue = "Something..."
tableCellView.someTextField.stringValue = "Blah..."
//...
let size = NSSize(width: 200, height: 50)
tableCellView.someTextField.setFrameSize(size)
tableCellView.someTextField.needsLayout = true
tableCellView.needsLayout = true
return tableCellView
})
For tableCellView.someTextField and tableCellView, I tried the following combination and nothing seems to change:
.needsDisplay = true
.needsLayout = true
.invalidateIntrinsicContentSize()
.layoutSubtreeIfNeeded()
.updateConstraints()
.layout()
Why is it so hard? My understanding is that if I set a new frame size for someTextField and then inform tableCellView that it needs to recalculate the subviews layout positions because someTextField has been modified so other subviews needs to reposition themselves to be consistent with auto layout constraints.
I'm attempting to implement an animation that shows/hides a view in a horizontal arrangement. I'd like this to happen with slide, and with no opacity changes. I'm using auto-layout everywhere.
Critically, the total width of the containing view changes with the window. So, constant-based animations are not possible (or so I believe, but happy to be proved wrong).
|- viewA -|- viewB -|
My first attempt was to use NSStackView, and animate the isHidden property of an arranged subview. Despite seeming like it might do the trick, I was not able to pull off anything close to what I was after.
My second attempt was to apply two constraints, one to force viewB to be zero width, and a second to ensure the widths are equal. On animation I change the priorities of these constraints from defaultHigh <-> defaultLow.
This results in the correct layout in both cases, but the animation is not working out.
With wantsLayer = true on the containing view, no animation occurs whatsoever. The views just jump to their final states. Without wantsLayer, the views do animate. However, when collapsing, viewA does a nice slide, but viewB instantly disappears. As an experiment, I changed the zero width to a fixed 10.0, and with that, the animation works right in both directions. However, I want the view totally hidden.
So, a few questions:
Is it possible to animate layouts like this with layer-backed views?
Are there other techniques possible for achieving the same effect?
Any ideas on how to achieve these nicely with NSStackView?
class LayoutAnimationViewController: NSViewController {
let containerView: NSView
let view1: ColorView
let view2: ColorView
let widthEqualContraint: NSLayoutConstraint
let widthZeroConstraint: NSLayoutConstraint
init() {
self.containerView = NSView()
self.view1 = ColorView(color: NSColor.red)
self.view2 = ColorView(color: NSColor.blue)
self.widthEqualContraint = view2.widthAnchor.constraint(equalTo: view1.widthAnchor)
widthEqualContraint.priority = .defaultLow
self.widthZeroConstraint = view2.widthAnchor.constraint(equalToConstant: 0.0)
widthZeroConstraint.priority = .defaultHigh
super.init(nibName: nil, bundle: nil)
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func loadView() {
self.view = containerView
// view.wantsLayer = true
view.addSubview(view1)
view.addSubview(view2)
view.subviewsUseAutoLayout = true
NSLayoutConstraint.activate([
view1.topAnchor.constraint(equalTo: view.topAnchor),
view1.bottomAnchor.constraint(equalTo: view.bottomAnchor),
view1.leadingAnchor.constraint(equalTo: view.leadingAnchor),
// view1.trailingAnchor.constraint(equalTo: view2.leadingAnchor),
view2.topAnchor.constraint(equalTo: view.topAnchor),
view2.bottomAnchor.constraint(equalTo: view.bottomAnchor),
view2.leadingAnchor.constraint(equalTo: view1.trailingAnchor),
view2.trailingAnchor.constraint(equalTo: view.trailingAnchor),
widthEqualContraint,
widthZeroConstraint,
])
}
func runAnimation() {
view.layoutSubtreeIfNeeded()
self.widthEqualContraint.toggleDefaultPriority()
self.widthZeroConstraint.toggleDefaultPriority()
// self.leadingConstraint.toggleDefaultPriority()
NSAnimationContext.runAnimationGroup({ (context) in
context.allowsImplicitAnimation = true
context.duration = 3.0
self.view.layoutSubtreeIfNeeded()
}) {
Swift.print("animation complete")
}
}
}
extension LayoutAnimationViewController {
#IBAction func runTest1(_ sender: Any?) {
self.runAnimation()
}
}
Also, some potentially relevant, but so far unhelpful, related questions:
Animating Auto Layout changes concurrently with NSPopover contentSize change
Animating Auto Layout constraints with NSView.layoutSubtreeIfNeeded() not working on macOS High Sierra
Hide view item of NSStackView with animation
I wonder why my textview text didn't show up from starting text.
This is the image from my Xcode IB
When I run it on my iPhone 6 Simulator and others
Actually it should start from "Example Notification...."
Please help me out.
Those who didn't start UITextView from start,here is the answer.I am sure it worked 100% on iOS 8 and higher on any devices.
1.You need to deselect these at your view controller where textview is applied
Go to ViewController > Attribute Inspector > Search Extend Edges > Under Top Bars & Under Button Bars
2.Add the following code at your view controller
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
self.yourTextView.setContentOffset(CGPoint.zero, animated: false)
}
Special Thanks to #El Captain
To maintain UINavigationBar translucent and allow user to rotate the device while reading UITextView I used something like this:
private var firstLayout = true
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
if firstLayout {
firstLayout = false
textView.setContentOffset(
CGPoint(x: 0, y: -topLayoutGuide.length), animated: false)
}
}
Tested on iOS 9 and iOS 12 Beta.
In my case it was iOS 13. UITextView was constrained to edges. It's content was set on did load, after that text view automatically scrolled to the bottom causing large title to shrink.
What helped me is to wrap setText in to async:
DispatchQueue.main.async {
textView.text = logs
}
You can also keep UINavigationBar isTranslucent and UIScrollViewContentInsetAdjustmentAutomatic,
Just to fix the textView is hidden by navigationBar, then add the below code:
- (void)viewDidLayoutSubviews {
[super viewDidLayoutSubviews];
[textView setContentOffset:CGPointMake(0, -self.view.layoutMargins.top) animated:NO];
}
I have a UIScrollView inside a UIViewController (subclassed by ImageViewController). The ViewController itself is part of a NavigationController's stack. Now, apart from having a navigation bar, I want the ScrollView to take all of the available room on the screen. The UIImageView inside the scrollview should then fill the available room of the scroll view. You can see the current state at the bottom of this posting.
class ImageViewController: UIViewController, UIScrollViewDelegate {
#IBOutlet weak var scrollView: UIScrollView!
var imageView: UIImageView?
var image: UIImage?
override func viewDidLoad() {
super.viewDidLoad()
scrollView.delegate = self
if let image = image {
imageView = UIImageView(image: image)
if let imageView = imageView {
imageView.frame = CGRect(origin: CGPoint(x: 0, y: 0), size: image.size)
scrollView.addSubview(imageView)
scrollView.contentSize = image.size
let scaleHeight = scrollView.frame.size.height / scrollView.contentSize.height
let scaleWidth = scrollView.frame.size.width / scrollView.contentSize.width
let minimumScale:CGFloat = min(scaleHeight, scaleWidth)
let maximumScale:CGFloat = max(scaleHeight, scaleWidth)
scrollView.minimumZoomScale = minimumScale
scrollView.maximumZoomScale = maximumScale
scrollView.zoomScale = maximumScale
}
}
}
func viewForZoomingInScrollView(scrollView: UIScrollView) -> UIView? {
return imageView
}
}
The code leaves me with unnecessary borders (left, right, top). How do I get rid of them?
EDIT: With #Bxtr's suggestion and another stackoverflow thread I was able to remove the borders left and right to the scroll view. After some more digging I found out that by deactivating Adjust Scroll View Insets, the image inside the scroll view can be correctly vertically positioned. Still, I do not get the reason for the vertical misplacement in the first place...
Have you checked the margin/padding values, because it kinda looks so (same size on left and right border). If it is not the case, could you please also post your xml file of the activity so we can have every part of the puzzle to help you ?
scrollView.contentSize = image.size;
you have to tweek this line. You are explicitly setting scroll view content size to the image size. You have to set content size to fit the Width of Screen.
You can use a UIView in UIScrollView, and that UIView contains UIImage.
You need to set constraints properly.
After some more digging I found out that by deactivating Adjust Scroll
View Insets, the image inside the scroll view can be correctly
vertically positioned. Still, I do not get the reason for the vertical
misplacement in the first place...
The reason is that the view controller's automaticallyAdjustsScrollViewInsets property is by default YES, the following is from apple documentation:
automaticallyAdjustsScrollViewInsets
A Boolean value that indicates
whether the view controller should automatically adjust its scroll
view insets.
Default value is YES, which allows the view controller to adjust its
scroll view insets in response to the screen areas consumed by the
status bar, navigation bar, and toolbar or tab bar. Set to NO if you
want to manage scroll view inset adjustments yourself, such as when
there is more than one scroll view in the view hierarchy.
Besides setting automaticallyAdjustsScrollViewInsets = No, you can pin the scrollView to the topLayoutGuide (instead of to the top of the viewController's view) when using autoLayout.
I have a simple view that displays an NSBezierpath. On mouseDown inside the path, the path's fill color sets to yellow and the view redraws. On mouseDown outside the path, the path's fill color sets to blue and the view redraws.
In my storyboard, I have a single window controller with a window content segue to a view controller. The view, customview class HeartView (below) fills the entire view controller.
Everything works fine until the user resizes the window vertically. After that, the view exhibits bizarre behavior: mouseDown no longer works everywhere inside the path, the recolor sometimes happens on mouseDown outside the path, and the path sometimes (but not always) doesn't completely fill. I think something is going on in the superview, but I don't know what.
import Cocoa
class HeartView: NSView {
var mouseLocation : NSPoint = NSZeroPoint
func drawObject(){
//Create an empty Bezier path
let aBezier : NSBezierPath = NSBezierPath()
aBezier.moveToPoint(CGPoint(x: 176.95,y: 44.90))
aBezier.curveToPoint(CGPoint(x: 166.71,y: 145.89),
controlPoint1: CGPoint(x: 76.63,y: 76.78),
controlPoint2: CGPoint(x: 82.59,y: 206.70))
aBezier.curveToPoint(CGPoint(x: 176.95,y: 44.90),
controlPoint1: CGPoint(x: 237.55,y: 224.76),
controlPoint2: CGPoint(x: 276.83,y: 95.98))
aBezier.closePath()
if (aBezier.containsPoint(NSMakePoint(mouseLocation.x, mouseLocation.y))){
NSColor.yellowColor().setFill()
NSColor.greenColor().setStroke()
} else {
NSColor.blueColor().setFill()
NSColor.orangeColor().setStroke()
}
aBezier.fill()
aBezier.lineWidth = 2.0
aBezier.stroke()
}
override func drawRect(dirtyRect: NSRect) {
super.drawRect(dirtyRect)
drawObject()
}
override func mouseDown(theEvent: NSEvent) {
mouseLocation.x = theEvent.locationInWindow.x
mouseLocation.y = theEvent.locationInWindow.y
self.setNeedsDisplayInRect(self.frame)
}
}
I found the answer in Lucas Derraugh's video on Mouse Events (Cocoa Programming L27). Turns out, I was capturing the mouseDown event in the superview's coordinate system. In the mouseDown event, I used "locationInWindow," which is what caused the strange behavior. I changed the method to:
override func mouseDown(theEvent: NSEvent) {
var viewPoint:NSPoint = self.convertPoint(theEvent.locationInWindow, fromView: nil)
mouseLocation.x = viewPoint.x
mouseLocation.y = viewPoint.y
self.needsDisplay = true
}
to convert from the window's coordinate system to the view's. Things now work well after any window resize event.