I am trying to create a UIView with round corners the round corners are rendering perfectly but there is an odd black background behind the view. How do I get rid of the black background?
CODE
import UIKit
import PlaygroundSupport
// The background rectange for main view
let backgroundRectangle = CGRect(x: 0, y: 0, width: 500, height: 500)
// Main view
let mainView = UIView(frame: backgroundRectangle)
// Color of the main view
mainView.backgroundColor = .darkGray
// Corner radius
mainView.layer.cornerRadius = 50
mainView.layer.masksToBounds = false
// Present the view to Playground's live view
PlaygroundPage.current.liveView = mainView
RENDERED UI
EDIT
import UIKit
import PlaygroundSupport
// Holder rectangle
let holderRectangle = CGRect(x: 0, y: 0, width: 500, height: 500)
// Holder view
let holderView = UIView(frame: holderRectangle)
// The background color of the holder view is clear
holderView.backgroundColor = .clear
// Main rectangle
let mainRectangle = CGRect(x: 0, y: 0, width: 500, height: 500)
// Main view
let mainView = UIView(frame: mainRectangle)
// The background color of the main view is black
mainView.backgroundColor = .white
// Create a corner radius for the main view
mainView.layer.cornerRadius = 30
mainView.layer.masksToBounds = false
// Make the main view a subview of the holder view
holderView.addSubview(mainView)
// Present the holder view in the live view
PlaygroundPage.current.liveView = holderView
This is happening because, there is no other view present behind your mainView. Please add a view behind mainView or embed your mainView into UIView assign a background color of your choice to the newly created view. Thats it your issue resolved.
Related
I am trying to add UIView with the bottom border programatically to stack view.But border is not getting added to UIView().
Code to add UIView to stack view:
func addOtpViews()
{
var otpLength=Int(otpLen as String)!
print("otpLength is\(otpLength)")
var i=0;
while(i<=otpLength)
{
var view=UIView(frame: .zero)
addBottomBorderTo(view: view)
otpStackView.addArrangedSubview(view)
i=i+1
}
otpStackView.translatesAutoresizingMaskIntoConstraints=false
}
on the above otpStackView is a stack view which I have already added in StoryBoard.
code to add bottom line:
func addBottomBorderTo(view:UIView) {
print("bottom is added")
let layer = CALayer()
layer.backgroundColor = UIColor.gray.cgColor
layer.frame = CGRect(x: 0.0, y: view.frame.size.height - 2.0, width: view.frame.size.width, height: 2.0)
view.layer.addSublayer(layer)
}
Why bottom line is not added to UIView()?Please help me.Thanks in advance.
have you checked the view frame here
layer.frame = CGRect(x: 0.0, y: view.frame.size.height - 2.0, width: view.frame.size.width, height: 2.0)
view.frame could be (0,0),then you will not see the bottom line.
always be careful when you work with view frame.
My suggestions:
1.Adding sub view instead of adding sub layer,then use snapkit to layout.
2.Build a seperate view class called bottomedView,then add sub view there with snapkit.
3.Build a seperate view class called bottomedView,and draw your bottom line in onDraw.
Always be aware view frame may not be determined when view is missing unexpectedly.
What´s the difference between view and superview?
let fromViewController = self.source
let containerView = fromViewController.view.superview
Suppose that
let v1 = UIView()
parent.addSubview(v1)
here
v1 ----- >>> v1 ( The view itself )
v1.superview ------- >>> parent
Views are the fundamental building blocks of your app's user interface, and the UIView class defines the behaviors that are common to all views. A view object renders content within its bounds rectangle and handles any interactions with that content.
let rect = CGRect(x: 10, y: 10, width: 100, height: 100)
let myView = UIView(frame: rect)
The superview is the immediate ancestor of the current view. The value of this property is nil when the view is not installed in a view hierarchy. To set the value of this property, use the addSubview(_:) method to embed the current view inside another view.
let rect = CGRect(x: 10, y: 10, width: 100, height: 100)
let myView = self.view.addSubview( UIView(frame: rect))
I want to show view in statusbar which should be visible to my all View Controller
Example: I need to show "No Internet Connection" in status bar and it will hide after we get connectivity of internet?
You can add a view directly to the status bar:
// get the status bar
let statusBar = UIApplication.shared.value(forKey: "statusBarWindow") as? UIWindow
// create a subview & add it to the status bar
let subview = UIView(frame: CGRect(x: 20, y: 0, width: 20, height: 10))
subview.backgroundColor = .red
statusBar?.addSubview(subview)
statusBar?.bringSubview(toFront: subview)
If you declare the statusBar and the noNetworkConnectionView globally, you can access it from anywhere to show or hide it dynamically.
Result:
Disclaimer: I am not sure whether Apple will approve apps that modify the status bar in this way.
Create a view
let statusView = UIView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.size.width, height: 40))
statusView.tag = 1101 //used to get view whenever required
statusView.backgroundColor = UIColor.red.withAlphaComponent(0.6)
//set other properties
Show view on window
//show on window, will be visible in all view controller
UIApplication.shared.delegate?.window??.addSubview(statusView)
UIApplication.shared.delegate?.window??.bringSubview(toFront: statusView)
Hide View
//to hide that view
UIApplication.shared.delegate?.window??.viewWithTag(1101)?.removeFromSuperview()
I want to display a progress indicator at the center of the screen, NOT the view. It should be the center of the view because the view is scrollable. Most answers only tells how to center it in the view. I have this code:
let screenBound = UIScreen.main.bounds
let progressIndc = UIActivityIndicatorView()
progressIndc.frame = CGRect(x: screenBound.width / 2 - 10,
y: screenBound.height / 2 - 10,
width: 20, height: 20)
progressIndc.hidesWhenStopped = true
progressIndc.color = UIColor.gray
progressIndc.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.gray
// self.view is scroll view
self.view.addSubview(progressIndc)
progressIndc.startAnimating()
But it shown near the top in iPhone 7. What should be the right way? I can also do a blocking pop-up dialog with a progress indicator.
if you want to keep the indicator view at the center of screen while scrolling, you can add a overlay view to the current topmost UIWindow, then add your indicator view to the overlay view:
guard let topWindow = UIApplication.shared.windows.last else {return}
let overlayView = UIView(frame: topWindow.bounds)
overlayView.backgroundColor = UIColor.clear
topWindow.addSubview(overlayView)
let hudView = UIActivityIndicatorView()
hudView.bounds = CGRect(x: 0, y: 0, width: 20, height: 20)
overlayView.addSubview(hudView)
hudView.center = overlayView.center
you should do this after the topmost UIViewController's view was attached on the top UIWindow, for example, in viewDidAppearmethod.
you can use center property of UIView
progressIndc.center = self.view.center
for e.g
let screenBound = UIScreen.main.bounds
let progressIndc = UIActivityIndicatorView()
progressIndc.frame = CGRect(x: screenBound.width / 2 - 10,
y: screenBound.height / 2 - 10,
width: 20, height: 20)
progressIndc.hidesWhenStopped = true
progressIndc.color = UIColor.gray
progressIndc.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.gray
// self.view is scroll view
progressIndc.center = self.view.center
self.view.addSubview(progressIndc)
progressIndc.startAnimating()
output
you can try this one to add you indicator on top of the screen. but it's not pretty solution -
AppDelegate.sharedInstance.window?.addSubview(progressIndc);
I have this class:
extension UIViewController {
func waiting() -> UIView{
let strLabel = UILabel(frame: CGRect(x: 50, y: 0, width: 200, height: 50))
strLabel.text = "Aguarde..."
strLabel.textColor = UIColor.whiteColor()
let messageFrame = UIView(frame: CGRect(x: view.frame.midX - 90, y: view.frame.midY - 25 , width: 180, height: 50))
messageFrame.layer.cornerRadius = 15
messageFrame.backgroundColor = UIColor(white: 0, alpha: 0.40)
let activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: UIActivityIndicatorViewStyle.White)
activityIndicator.frame = CGRect(x: 0, y: 0, width: 50, height: 50)
activityIndicator.startAnimating()
messageFrame.addSubview(activityIndicator)
messageFrame.addSubview(strLabel)
view.addSubview(messageFrame)
return messageFrame
}
}
When I need use this class I use:
class MyController: UIViewController{
....
func x(){
let messageFrame = waiting()
//my code
messageFrame.removeFromSuperview()
}
}
The problem is when the frame is showed if I touch anywhere on my app this frame is hidden. I need that when this frame is showed other options staying disabled, when I finish the frame, the options of app is enabled again. How can I do it?
Change the view that you are returning a bit:
Make a "container" view that has the same frame as the view controller's view. Give this view a "clear" background.
Make a "background" view, same size as the "container" view and add it to the container. Give this view a black background and an alpha of, say, 0.4.
Now put the view that you are currently building in your "waiting" method, and add it to the "container" view (NOT to the background view, this should be a sibling of the background view, otherwise your alert will also be transparent).
Make sure all user interaction is disabled on your views (might only need it disabled on the "container" view).
This gives you a container view that covers the entire screen, and it has 2 children: a transparent background of the same size, and your current "waiting" alert thing.
Now if you add the "container" view to your view controller's view, the user can only touch on the container view which does nothing.
(Keep in mind that this doesn't handle screen rotation...you will have to do that yourself if needed.)