I'm trying to create some Constraints for a button that is moved with the UIPanGestureRecognizer
button.setTranslatesAutoresizingMaskIntoConstraints(false)
let line = ("\(p.x % snapX)")
let column = ("\(p.x % snapY)")
let constraint2 = NSLayoutConstraint(item: button, attribute: .CenterX, relatedBy: .Equal, toItem: view, attribute: .CenterX, multiplier: 1, constant: CGFloat(line))
let constraint3 = NSLayoutConstraint(item: button, attribute: .CenterY, relatedBy: .Equal, toItem: view, attribute: .CenterY, multiplier: 1, constant: CGFloat(column))
view.addConstraints([constraint2,constraint3])
but i have a "could not find member 'CenterX' error
P.s. line and column may take for example the value 27.6666564941406 and 0.666656494140625
Looks like the compiler is trying to find CenterX on the wrong enum type. Try using the full enum definition:
NSLayoutAttribute.CenterX
and
NSLayoutAttribute.CenterY
Related
am trying to add Autolayout constraints from top to my label view using this line of code:
addConstraints(NSLayoutConstraint(item: titleLabel, attribute: .top, relatedBy: .equal, toItem: thumbnailImageView, attribute: .bottom, multiplier: 1, constant: 8))
but it showing me this error:
"Cannot convert value of type 'NSLayoutConstraint' to expected argument type '[NSLayoutConstraint]"
trying to make the title label in purple color in image which I added
enter image description here
I searched it on google an see many solutions but that's about to activate the constraints withVisualFormate but am trying to do it with the above line of code
anyone plz help me out
Thanks
addConstraints([NSLayoutConstraint(item: titleLabel, attribute: .top, relatedBy: .equal, toItem: thumbnailImageView, attribute: .bottom, multiplier: 1, constant: 8)])
OR
addConstraint(NSLayoutConstraint(item: titleLabel, attribute: .top, relatedBy: .equal, toItem: thumbnailImageView, attribute: .bottom, multiplier: 1, constant: 8))
I am looking for the proper way to add a caption to the top and bottom of any image in an imageview set to aspect fit. Seems simple enough, but the textbox doesnt seem to move most of the time and ends up in the center other times. Here is an example of a formula I tried for the top caption.
mainTextBox.center.y = mainImageView.center.y + (mainImageView.image!.size.height / 2) - (mainTextBox.frame.size.height / 2)
Updated with help from Vandan Patel:
I have also tried manually setting constraints manually buy receive an error
let titleLabelWidth = NSLayoutConstraint(item: mainTextBox, attribute: NSLayoutAttribute.Width, relatedBy: NSLayoutRelation.Equal, toItem: nil, attribute: NSLayoutAttribute.Width, multiplier: 0.9, constant: 0)
let titleLabelCenterX = NSLayoutConstraint(item: mainTextBox, attribute: NSLayoutAttribute.CenterX, relatedBy: NSLayoutRelation.Equal, toItem: nil, attribute: NSLayoutAttribute.CenterX, multiplier: 1, constant: 0)
let titleLabelCenterY = NSLayoutConstraint(item: mainTextBox, attribute: NSLayoutAttribute.CenterY, relatedBy: NSLayoutRelation.Equal, toItem: nil, attribute: NSLayoutAttribute.CenterY, multiplier: 1, constant: 0)
let titleLabelHeight = NSLayoutConstraint(item: mainTextBox, attribute: NSLayoutAttribute.Height, relatedBy: NSLayoutRelation.Equal, toItem: nil, attribute: NSLayoutAttribute.Height, multiplier: 0.9, constant: 0)
mainTextBox.addConstraints([titleLabelWidth, titleLabelCenterX, titleLabelCenterY, titleLabelHeight])
* Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '* +[NSLayoutConstraint constraintWithItem:attribute:relatedBy:toItem:attribute:multiplier:constant:]: 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'
Are you looking for something like this?
//title-Label Constraints
let titleLabelWidth = NSLayoutConstraint(item: titleLabel, attribute: .width, relatedBy: .equal, toItem: blurEffectView, attribute: .width, multiplier: 0.9, constant: 0)
let titleLabelCenterX = NSLayoutConstraint(item: titleLabel, attribute: .centerX, relatedBy: .equal, toItem: blurEffectView, attribute: .centerX, multiplier: 1, constant: 0)
let titleLabelCenterY = NSLayoutConstraint(item: titleLabel, attribute: .centerY, relatedBy: .equal, toItem: blurEffectView, attribute: .centerY, multiplier: 1, constant: 0)
let titleLabelHeight = NSLayoutConstraint(item: titleLabel, attribute: .height, relatedBy: .equal, toItem: blurEffectView, attribute: .height, multiplier: 0.9, constant: 0)
self.addConstraints([titleLabelWidth, titleLabelCenterX, titleLabelCenterY, titleLabelHeight])
I am not sure what I am missing here, I have been going at this for hours, looks at constant tutorials, and I am still getting an issue with conflicting constraints. Basically I have a button, and on this button I want to add a new view that is center to the button and the same size. When I go to apply the constraints, it is telling me that there are conflicting constraints, and I am just not understanding what can be conflicting here.
//Create a new view
let selectBorderView = UIView();
//Guarantee there are no constraints attached to it
NSLayoutConstraint.deactivateConstraints(selectBorderView.constraints);
//Add the new view to the button
sender.addSubview(selectBorderView);
//Create constraint selectBorderView.width = button.width
let constraintEW = NSLayoutConstraint(item: selectBorderView, attribute: .Width, relatedBy: .Equal, toItem: selectBorderView.superview, attribute: .Width, multiplier: 1, constant: 0);
//Create constraint selectBorderView.height = button.height
let constraintEH = NSLayoutConstraint(item: selectBorderView, attribute: .Height, relatedBy: .Equal, toItem: selectBorderView.superview, attribute: .Height, multiplier: 1, constant: 0);
//Create constraint selectBorderView.centerX = button.centerX
let constraintCX = NSLayoutConstraint(item: selectBorderView, attribute: .CenterX, relatedBy: .Equal, toItem: selectBorderView.superview!, attribute: .CenterX, multiplier: 1, constant: 0);
//Create constraint selectBorderView.centerY = button.centerY
let constraintCY = NSLayoutConstraint(item: selectBorderView, attribute: .CenterY, relatedBy: .Equal, toItem: selectBorderView.superview, attribute: .CenterY, multiplier: 1, constant: 0);
//add the constraints to the button
selectBorderView.superview!.addConstraint(constraintEW);
selectBorderView.superview!.addConstraint(constraintEH);
selectBorderView.superview!.addConstraint(constraintCX);
selectBorderView.superview!.addConstraint(constraintCY);
You are likely seeing an error message that says something like:
Unable to simultaneously satisfy constraints. Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints)
If you see that warning, you should set translatesAutoresizingMaskIntoConstraints to false:
selectBorderView.translatesAutoresizingMaskIntoConstraints = false
Could anyone help me I have this simple view that is very simple to do if I'm using story board but all of my UILabel is based on somewhere(API) that is why I need to create my view programmatically.
this is the view I would like to achieved
what I accomplished at the moment are pinning the top label in its position and adding leading space on label 1, 2, & 3
basically what i need are:
pin the label 1 to the top label
pin the label 3 to bottom
add vertical spaces to label 1,2,3
have equal width and height constraint in label 1,2 ,3
this is my code so far.
private func addTopConstraint(from:AnyObject,to:AnyObject,cons:CGFloat){
let topConstraint = NSLayoutConstraint(item: from, attribute: .Top, relatedBy: .Equal, toItem: to, attribute: .Bottom, multiplier: 1.0, constant: cons)
self.view.addConstraint(topConstraint)
}
private func addVerticalSpace(from:AnyObject,to:AnyObject,cons:CGFloat){
let verticalSpace = NSLayoutConstraint(item: from, attribute: .Bottom, relatedBy: .Equal, toItem: to, attribute: .Bottom, multiplier: 1.0, constant: cons)
self.view.addConstraint(verticalSpace)
}
private func addLeadingSpace(from:AnyObject,to:AnyObject,cons:CGFloat){
let leadingSpace = NSLayoutConstraint(item: from, attribute: .Leading, relatedBy: .Equal, toItem: to, attribute: .Leading, multiplier: 1.0, constant: cons)
self.view.addConstraint(leadingSpace)
}
private func sameWidthAndHeight (from:AnyObject,to:AnyObject){
let width = NSLayoutConstraint(item: from, attribute: .Width, relatedBy: .Equal, toItem: to, attribute: .Width, multiplier: 1.0, constant: 0)
let height = NSLayoutConstraint(item: from, attribute: .Height, relatedBy: .Equal, toItem: to, attribute: .Height, multiplier: 1.0, constant: 0)
self.view.addConstraint(width)
self.view.addConstraint(height)
}
but the sameWidthAndHeight and addVerticalSpace function fails
maybe it something to do with content hugging and priorities too, I'm not that sure since we're used to do this in storyboard.
could anyone share a thought? Thanks in advance
I am using Xcode 6.2 and Swift. I have set up with storyboard a UIScrollView which I fill with varying numbers of programmatically created buttons. Each button varies in height due to the data contained. All of this usually creates a list longer than a single screen thus requiring scroll ability. As I loop and create each button I also adjust the height of the button to meet the needs of the content. So, in short varying numbers of buttons of varying size. I am able to set the height for the scrollView by summing up each buttons height during creation. Suddenly I cannot scroll the buttons anymore. I have tried many of the suggestions made on this site for other related questions but none fix my problem.
some code:
// Add constraints depending on what number button it is
let heightConstraint:NSLayoutConstraint = NSLayoutConstraint(item: codeData, attribute: NSLayoutAttribute.Height, relatedBy: NSLayoutRelation.Equal, toItem: nil, attribute: NSLayoutAttribute.NotAnAttribute, multiplier: 1, constant: CGFloat(buttonHeight))
codeData.addConstraint(heightConstraint)
let leftMarginConstraint:NSLayoutConstraint = NSLayoutConstraint(item: codeData, attribute: NSLayoutAttribute.Left, relatedBy: NSLayoutRelation.Equal, toItem: self.scrollviewContentView, attribute: NSLayoutAttribute.Left, multiplier: 1, constant: 900)
let rightMarginConstraint:NSLayoutConstraint = NSLayoutConstraint(item: codeData, attribute: NSLayoutAttribute.Right, relatedBy: NSLayoutRelation.Equal, toItem: self.scrollviewContentView, attribute: NSLayoutAttribute.Right, multiplier: 1, constant: 900)
let topMarginConstraint:NSLayoutConstraint = NSLayoutConstraint(item: codeData, attribute: NSLayoutAttribute.Top, relatedBy: NSLayoutRelation.Equal, toItem: self.scrollviewContentView, attribute: NSLayoutAttribute.Top, multiplier: 1, constant: CGFloat(sumOfButtonTops))
self.scrollviewContentView.addConstraints([leftMarginConstraint,rightMarginConstraint, topMarginConstraint])
let contentViewHeight:NSLayoutConstraint = NSLayoutConstraint(item: self.scrollviewContentView, attribute: NSLayoutAttribute.Height, relatedBy: NSLayoutRelation.Equal, toItem: self.codeButtonArray[0], attribute: NSLayoutAttribute.Height, multiplier: 1, constant: CGFloat(sumOfButtonTops + 30))