iOS view visibility gone
Try this extension:
extension UIView {
func visiblity(gone: Bool, dimension: CGFloat = 0.0, attribute: NSLayoutAttribute = .height) -> Void {
if let constraint = (self.constraints.filter{$0.firstAttribute == attribute}.first) {
constraint.constant = gone ? 0.0 : dimension
self.layoutIfNeeded()
self.isHidden = gone
}
}
}
How you can use this....
@IBOutlet weak var testView: UIView?
@IBAction func testVisibilty(switchbutton: UISwitch) -> Void {
let viewHeight:CGFloat = switchbutton.isOn ? 100 : 0.0
self.testView?.visiblity(gone: !switchbutton.isOn, dimension: viewHeight)
// set visibility for width constraint
//let viewWidth:CGFloat = switchbutton.isOn ? 300 : 0.0
//self.testView?.visiblity(gone: !switchbutton.isOn, dimension: viewWidth, attribute: .width)
}
Here is result:
As I have worked on both iOS & Android, You need to play with constraint outlet in ios to achieve Android functioning. iOS Does not support automatically like Android native support on visibility GONE
& VISIBLE
You need to hook the outlet
of particular constraint
(it may vertical/horizontal/height) you need to set it to 0
& need to manage your UI.
To Hide:
self.viewYourConstraint.constant = 0
self.yourView.hidden = true
self.view.layoutIfNeeded()
To Show:
self.viewYourConstraint.constant = 100//your constant value
self.yourView.hidden = false
self.view.layoutIfNeeded()
Note: If other constraints will be affected because of the update to the constraint above, the following must also need to be called:
self.yourView.setNeedsUpdateConstraints()
Maybe you'd prefer this solution
extension UIView {
enum Visibility {
case visible
case invisible
case gone
}
var visibility: Visibility {
get {
let constraint = (self.constraints.filter{$0.firstAttribute == .height && $0.constant == 0}.first)
if let constraint = constraint, constraint.isActive {
return .gone
} else {
return self.isHidden ? .invisible : .visible
}
}
set {
if self.visibility != newValue {
self.setVisibility(newValue)
}
}
}
private func setVisibility(_ visibility: Visibility) {
let constraint = (self.constraints.filter{$0.firstAttribute == .height && $0.constant == 0}.first)
switch visibility {
case .visible:
constraint?.isActive = false
self.isHidden = false
break
case .invisible:
constraint?.isActive = false
self.isHidden = true
break
case .gone:
if let constraint = constraint {
constraint.isActive = true
} else {
let constraint = NSLayoutConstraint(item: self, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .height, multiplier: 1, constant: 0)
self.addConstraint(constraint)
constraint.isActive = true
}
}
}
}
then the usage is:
someView.visibility = .visible
someView.visibility = .invisible
someView.visibility = .gone
edit:
improving capabilities: will work from storyboard (just write: 'visible', 'invisible', 'gone') in the "Visibility State"
all constraints inside view should be less then a 1000
extension UIView {
enum Visibility: String {
case visible = "visible"
case invisible = "invisible"
case gone = "gone"
}
var visibility: Visibility {
get {
let constraint = (self.constraints.filter{$0.firstAttribute == .height && $0.constant == 0}.first)
if let constraint = constraint, constraint.isActive {
return .gone
} else {
return self.isHidden ? .invisible : .visible
}
}
set {
if self.visibility != newValue {
self.setVisibility(newValue)
}
}
}
@IBInspectable
var visibilityState: String {
get {
return self.visibility.rawValue
}
set {
let _visibility = Visibility(rawValue: newValue)!
self.visibility = _visibility
}
}
private func setVisibility(_ visibility: Visibility) {
let constraints = self.constraints.filter({$0.firstAttribute == .height && $0.constant == 0 && $0.secondItem == nil && ($0.firstItem as? UIView) == self})
let constraint = (constraints.first)
switch visibility {
case .visible:
constraint?.isActive = false
self.isHidden = false
break
case .invisible:
constraint?.isActive = false
self.isHidden = true
break
case .gone:
self.isHidden = true
if let constraint = constraint {
constraint.isActive = true
} else {
let constraint = NSLayoutConstraint(item: self, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .height, multiplier: 1, constant: 0)
// constraint.priority = UILayoutPriority(rawValue: 999)
self.addConstraint(constraint)
constraint.isActive = true
}
self.setNeedsLayout()
self.setNeedsUpdateConstraints()
}
}
}