Transparent background for modally presented viewcontroller

问题

I am using Parse & ParseUI. I want my PFLoginViewController subclass to have a transparent background. In the future, I want to lay a blurred view over the background.

But.... Once the animate-in of the PFLoginViewController is done, the background turns black... Whilst during the animation the background was transparent.

func presentLogin() {
    var loginViewController = LoginViewController()
    var signupViewController = SignUpViewController()

    loginViewController.fields = .UsernameAndPassword | .LogInButton | .PasswordForgotten | .SignUpButton | PFLogInFields.DismissButton
    signupViewController.fields = .UsernameAndPassword | .Email | .DismissButton | .SignUpButton
    loginViewController.delegate = self
    loginViewController.logInView.backgroundColor = UIColor.clearColor()
    loginViewController.logInView.opaque = false
    signupViewController.delegate = self

    loginViewController.signUpController = signupViewController

    self.presentViewController(loginViewController, animated: true) { () -> Void in
        //
    }
}

My logincontroller's used subclass:

class LoginViewController: PFLogInViewController {

    @IBOutlet weak var _nmcLogoLabel: UILabel!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
        let userName = SettingsManager.userName
        let password = SettingsManager.password

        self.logInView.usernameField.text = userName
        self.logInView.passwordField.text = password

        NSBundle.mainBundle().loadNibNamed("LoginViewBranding", owner: self, options: nil)[0] as? UIView

        self.logInView.logo = _nmcLogoLabel

    }

}

How can I make it transparent?

P.s. Applying the clearColor to the backgroundColor in the subclass makes no difference

回答1:

Fixed it.

The problem was that presentViewController does not keep the view that I was covering.

viewController.modalPresentationStyle = .overCurrentContext

did the trick.

回答2:

Part of the solution is hidden in the question. You need three lines to make the background transparent, viz. isOpaque = false backgroundColor = .clear & set the modalPresentationStyle

Here's the full solution. In the calling View Controller, call this function:

func presentModal() {
    let modalController = ModalViewController()
    modalViewController.modalPresentationStyle = .overCurrentContext
    present(modalViewController, animated: true, completion: nil)
}

And in ModalViewController's viewDidLoad():

override func viewDidLoad() {
    super.viewDidLoad()

    view.isOpaque = false
    view.backgroundColor = .clear // try other colors, say: .white or black with Alpha etc.
}

回答3:

same as the selected answer but visually through IB:

回答4:

In case anyone is still struggling with a transparent background I found this solution some time ago - I can't remember where but still works fine with the latest Xcode & Swift.

ContactListViewController2: UIViewController, UITableViewDelegate, UITableViewDataSource,UIViewControllerTransitioningDelegate {

required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)

    self.modalPresentationStyle = .custom
    self.transitioningDelegate = self
}

来源：https://stackoverflow.com/questions/27669699/transparent-background-for-modally-presented-viewcontroller

标签

swift

parse-platform

ios8.1