Mapbox iOS move attribution Button - ios

I'm using the mapbox SDK and I need to show their logo watermark and their attribution mark. I can move them though, so I want to move the attribution button from the bottom right to bottom left next to the logo watermark.
I tried the following code but it did not work:
func mapViewWillStartLoadingMap(_ mapView: MGLMapView) {
mapView.attributionButton.frame.offsetBy(dx: -200.0, dy: 0)
}
This is how it looks like:

I tried solutions like Harshal's but couldn't get that to work. Here's what worked for me (placing the attribution button near upper left). (Code added to viewDidLoad())
self.view.addConstraints([
NSLayoutConstraint(item: mapView.attributionButton, attribute: .width, relatedBy: .equal, toItem: nil, attribute: .width, multiplier: 1.0, constant: 25),
NSLayoutConstraint(item: mapView.attributionButton, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .height, multiplier: 1.0, constant: 25),
NSLayoutConstraint(item: mapView.attributionButton, attribute: .left, relatedBy: .equal, toItem: self.view, attribute: .left, multiplier: 1.0, constant: 72),
NSLayoutConstraint(item: mapView.attributionButton, attribute: .top, relatedBy: .equal, toItem: self.view, attribute: .top, multiplier: 1.0, constant: 24),
])

mapView.attributionButton.contentHorizontalAlignment = .left
mapView.attributionButton.frame.size = CGSize(width: self.mapView.frame.size.width - 120, height: 25)
you can also hide attribution Button as follow:
mapView.attributionButton.alpha = 0

Take a look at scaleBarPosition in MGLMapView
MapBox added the ability to do this in 4.3.0
https://github.com/mapbox/mapbox-gl-native/commit/60ceac5efc3d77199f773f08400fe1d53d5a1b90

Related

I need top constraint of unknow element

I have an app which is downloading image from server by clicking the button. After image have downloaded i create a new imageView and add it to the my contentView(UIView). I need to create the constraints - every new imageview need top constraint from previous one
func addNewImageToTheScrollView(img: UIImage?) {
if let imageResponse = img {
let imageView = UIImageView(image: imageResponse.crop(rect: CGRect(x: 0, y: imageResponse.size.height/2, width: self.contentView.frame.width, height: 200)))
self.contentView.addSubview(imageView)
imageView.translatesAutoresizingMaskIntoConstraints = false
let x = NSLayoutConstraint(item: imageView, attribute: .centerX, relatedBy: .equal, toItem: self.contentView, attribute: .centerX, multiplier: 1.0, constant: 0)
let y = NSLayoutConstraint(item: imageView, attribute: .top, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 30)
let width = NSLayoutConstraint(item: imageView, attribute: .width, relatedBy: .equal, toItem: self.contentView, attribute: .width, multiplier: 1.0, constant: 0)
let height = NSLayoutConstraint(item: imageView, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 150)
self.contentView.addConstraints([x, y])
imageView.addConstraints([width, height])
}
}
If i comment the constraint code, it will be work fine unless every new imageView will be on the same place, on the top of the View. Now whit this constraint code i have such code issue after downloading
2017-07-02 14:50:01.018 ImageFromServerTest[11516:1080948] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'NSLayoutConstraint for >: A multiplier of 0 or a nil second item together with a location for the first attribute creates an illegal constraint of a location equal to a constant. Location attributes must be specified in pairs.'
Whenever you are working with scrollViews, there are 2 thumb rules for it:-
Give the scrollView leading, trailing, bottom, and top constraint with respect to the superview, that is self.view
#IbOutlet weak var scrollView: UIScrollView!
let leading = NSLayoutConstraint(item: scrollView, attribute: .leading, relatedBy: .equal, toItem: self.view, attribute: .leadingMargin, multiplier: 1.0, constant: 0)
let trailing = NSLayoutConstraint(item: scrollView, attribute: .trailing, relatedBy: .equal, toItem: self.view, attribute: .trailingMargin, multiplier: 1.0, constant: 0)
let top = NSLayoutConstraint(item: scrollView, attribute: .top, relatedBy: .equal, toItem: self.view, attribute: .top, multiplier: 1.0, constant: 0)
let bottom = NSLayoutConstraint(item: scrollView, attribute: .bottom, relatedBy: .equal, toItem: self.view, attribute: .bottom, multiplier: 1.0, constant: 0)
Add constraints to the contentView with respect to the scrollView
#IbOutlet weak var contentView: UIView!
let leading = NSLayoutConstraint(item: contentView, attribute: .leading, relatedBy: .equal, toItem: scrollView, attribute: .leading, multiplier: 1.0, constant: 0)
let trailing = NSLayoutConstraint(item: contentView, attribute: .trailing, relatedBy: .equal, toItem: scrollView, attribute: .trailing, multiplier: 1.0, constant: 0)
let top = NSLayoutConstraint(item: contentView, attribute: .top, relatedBy: .equal, toItem: scrollView, attribute: .top, multiplier: 1.0, constant: 0)
//increase the constant according to how much long you need the scrollview to be
let bottom = NSLayoutConstraint(item: contentView, attribute: .bottom, relatedBy: .equal, toItem: scrollView, attribute: .bottom, multiplier: 1.0, constant: 0)
Now add your subviews constraints (labels, images) with respect to the contentView
For example- You received your first image, so we will maintain an array of UIImageViews outside your function.
var imageViews = [UIImageViews]() //declared outside the function
//received an image here
var imageView = UIImageView() // define the frame according to yourself using frame init method
imageView.image = image
if imageViews.isEmpty { // first image view
//add constraints to first image view
let x = NSLayoutConstraint(item: imageView, attribute: .centerX, relatedBy: .equal, toItem: contentView, attribute: .centerX, multiplier: 1.0, constant: 0)
let y = NSLayoutConstraint(item: imageView, attribute: .top, relatedBy: .equal, toItem: contentView, attribute: .top, multiplier: 1.0, constant: 30)
let width = NSLayoutConstraint(item: imageView, attribute: .width, relatedBy: .equal, toItem: self.contentView, attribute: .width, multiplier: 1.0, constant: 0)
let height = NSLayoutConstraint(item: imageView, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 150)
}
else { //second, third, fourth image view... so on
let x = NSLayoutConstraint(item: imageView, attribute: .centerX, relatedBy: .equal, toItem: contentView, attribute: .centerX, multiplier: 1.0, constant: 0)
let y = NSLayoutConstraint(item: imageView, attribute: .top, relatedBy: .equal, toItem: imageViews[imageViews.count - 1], attribute: .bottom, multiplier: 1.0, constant: 30)
let width = NSLayoutConstraint(item: imageView, attribute: .width, relatedBy: .equal, toItem: self.contentView, attribute: .width, multiplier: 1.0, constant: 0)
let height = NSLayoutConstraint(item: imageView, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 150)
}
imageViews.append(imageView)
}
Hope you got an idea now, how to proceed with this problem. If having more than 4 or 5 imageviews, you'll probably want to check the count of the array and increase the contentView of the scrollView accordingly. you can do so by using
self.scrollView.contentSize = CGSize(width, height)
I believe you have a problem here:
let y = NSLayoutConstraint(item: imageView, attribute: .top, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 30)
"toItem" parameter should have some value. Also first parameter should be imageView.topAnchor. Probably it should look something like this:
let y = NSLayoutConstraint(item: imageView.topAnchor, attribute: .top, relatedBy: .equal, toItem: self.contentView.topAnchor, attribute: .notAnAttribute, multiplier: 1.0, constant: 30)

Xcode adds duplicate constraints?

In code I added 4 constraints. But when I run the app, in UI debugger, it shows additional 6 constraints? It should be all clear with these 4 I added. I don't know what I'm doing wrong?
let leftConstr = NSLayoutConstraint(item: image, attribute: .leading, relatedBy: .equal, toItem: cell.contentView, attribute: .leading, multiplier: 1.0, constant: 0.0)
let bottomConstr = NSLayoutConstraint(item: image, attribute: .bottom, relatedBy: .equal, toItem: cell.contentView , attribute: .bottom, multiplier: 1.0, constant: 0.0)
let highthConstr = NSLayoutConstraint(item: image, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant: 15)
let widthConstr = NSLayoutConstraint(item: image, attribute: .width, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant: 50)
cell.contentView.addConstraints([highthConstr, widthConstr, bottomConstr, leftConstr])
Here is the screenshot of my UI debugger
Maybe you can try to add this line of code before :
image.translatesAutoresizingMaskIntoConstraints = false

NSLayoutConstraints breaking but seem fine

I'm trying to pin an image view to the top, left, and right of a superview, and give it a height with NSLayoutConstraint like so:
backgroundView.addSubview(imageView)
backgroundView.addConstraint(NSLayoutConstraint(item: imageView, attribute: .Top, relatedBy: .Equal, toItem: backgroundView, attribute: .Top, multiplier: 1.0, constant: 0.0))
backgroundView.addConstraint(NSLayoutConstraint(item: imageView, attribute: .Left, relatedBy: .Equal, toItem: backgroundView, attribute: .Left, multiplier: 1.0, constant: 0.0))
backgroundView.addConstraint(NSLayoutConstraint(item: imageView, attribute: .Right, relatedBy: .Equal, toItem: backgroundView, attribute: .Right, multiplier: 1.0, constant: 0.0))
backgroundView.addConstraint(NSLayoutConstraint(item: imageView, attribute: .Height, relatedBy: .Equal, toItem: nil, attribute: .NotAnAttribute, multiplier: 1.0, constant: view.bounds.width))
But the image doesn't show up and the debugger is logging that my constraints are broken. I don't see what constraint could be causing the problem.
fixed by adding imageView.translatesAutoresizingMaskIntoConstraints = false before adding the imageView as a subview to backgroundView.

Move Ad Banner down below Status Bar using NSLayoutConstraint Swift

In Swift, I am trying to add a Google Smart Ad Banner using NSLayoutConstraints at the top of the view, but below the status bar by 14 points. I've been trying for ages now with various different attributes and top or topLayoutGuide.
Link to Image
let xConstraint = NSLayoutConstraint(item: bannerView, attribute: .centerX,
relatedBy: .equal, toItem: self.view, attribute: .centerX, multiplier: 1, constant: 0)
let pinTop = NSLayoutConstraint(item: bannerView, attribute: .top,
relatedBy: .equal, toItem: self.topLayoutGuide, attribute: .top, multiplier: 1, constant: 14)
self.view.addSubview(bannerView)
self.view.addConstraint(xConstraint)
self.view.addConstraint(pinTop)
You’re pinning the banner to the top of the topLayoutGuide, but what you really want is the bottom of the topLayoutGuide, so that it will start below the status bar:
let pinTop = NSLayoutConstraint(item: bannerView,
attribute: .top,
relatedBy: .equal,
toItem: self.topLayoutGuide,
attribute: .bottom,
multiplier: 1,
constant: 14)

UITextField autolayout with margins programmatically

I'm new to AutoLayout and would like to display my UITextField at 100% width with a consistent 15px left and right margin, like so:
Typically I would do this using CGRect, setting the width to the containing view's width minus 30px, then offset the left side by 15px:
searchTextField.frame = CGRectMake(15, 0, view.frame.width - 30, 50)
But I'd like to learn AutoLayout for this sort of thing, since it's the way to go these days. I should note that I am doing everything programmatically -- no Storyboards here.
I'd love it if someone could help me out!
Update
Wow! Thank you for all the responses. I believe all of them would achieve what I'm trying to do, but there can only be one :)
Usually I use for this cocoapod that is dealing with constraints, but if you need pure apple solution documentation states:
You have three choices when it comes to programmatically creating
constraints: You can use layout anchors, you can use the
NSLayoutConstraint class, or you can use the Visual Format Language.
Approach with NSLayoutConstraints in your case would be:
NSLayoutConstraint(item: textField, attribute: .Leading, relatedBy: .Equal, toItem: parentView, attribute: .LeadingMargin, multiplier: 1.0, constant: 15.0).active = true
NSLayoutConstraint(item: textField, attribute: .Trailing, relatedBy: .Equal, toItem: parentView, attribute: .TrailingMargin, multiplier: 1.0, constant: -15.0).active = true
NSLayoutConstraint(item: textField, attribute: .Top, relatedBy: .Equal, toItem: parentView, attribute: .TopMargin, multiplier: 1.0, constant: 50.0).active = true
Remember that if you don't have any constraints in the view, they would be added automatically and you'll have to deal with them and conflicts that would be created by adding new constraints on runtime. To avoid this you could either create textField manually and add it to the view or set constraints with low priority in the Interface Builder .
Assuming the parent of the text field is view, do this after view.addSubview(searchTextField):
NSLayoutConstraint.activateConstraints([
searchTextField.leadingAnchor.constraintEqualToAnchor(view.leadingAnchor, constant: 15),
searchTextField.trailingAnchor.constraintEqualToAnchor(view.trailingAnchor, constant: -15),
])
Use this code:
let topConstraint = NSLayoutConstraint(item: textField, attribute: NSLayoutAttribute.Top, relatedBy: .Equal, toItem: self.view, attribute: NSLayoutAttribute.Top, multiplier: 1.0, constant: 0)
let trailingConstraint = NSLayoutConstraint(item: textField, attribute: NSLayoutAttribute.Trailing, relatedBy: .Equal, toItem: self.view, attribute: NSLayoutAttribute.Trailing, multiplier: 1.0, constant: 15)
let leadingConstraint = NSLayoutConstraint(item: textField, attribute: NSLayoutAttribute.Leading, relatedBy: .Equal, toItem: self.view, attribute: NSLayoutAttribute.Leading, multiplier: 1.0, constant: 15)
let heightConstraint = NSLayoutConstraint(item: textField, attribute: NSLayoutAttribute.Height, relatedBy: .Equal, toItem: nil, attribute: NSLayoutAttribute.NotAnAttribute, multiplier: 1.0, constant: 50)
self.view.addConstraint(topConstraint )
self.view.addConstraint(trailingConstraint)
self.view.addConstraint(leadingConstraint)
self.view.addConstraint(heightConstraint)
Set the constraints in storyboard.
Click on the text field then click on in the bottom left. From there you can choose constraints like that.
To use Auto Layout, you need to define constraints for your text field.Here, I have created four constraints(Leading, Trailing, Top and Height) related to its superview.
func addLabelConstraints(superView:UIView) {
let leading = NSLayoutConstraint(item: searchTextField, attribute: .Leading, relatedBy: .Equal, toItem: superView, attribute: .Leading, multiplier: 1, constant: 15)
superview!.addConstraint(leading)
let trailing = NSLayoutConstraint(item: searchTextField, attribute: .Trailing, relatedBy: .Equal, toItem: superView, attribute: .Trailing, multiplier: 1, constant: 15)
superView.addConstraint(trailing)
let top = NSLayoutConstraint(item: searchTextField, attribute: .Top, relatedBy: .Equal, toItem: superView, attribute: .Top, multiplier: 1, constant: 0)
superView.addConstraint(top)
let height = NSLayoutConstraint(item: searchTextField, attribute: .Height, relatedBy: .Equal, toItem: nil, attribute: .Height, multiplier: 0, constant: 50)
superView.addConstraint(height)
}

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