/////////////////////////////////////////////////// Tested
//                                            ///////
//                implementation                ///////
//                Part 2                        ///////
//                                            ///////
///////////////////////////////////////////////////
//here we call Toast Bubble it inside our button "just copy it in your controller"
 @IBOutlet weak var txtPassword: UITextField!
    @IBOutlet weak var txtUserName: UITextField!
    
    //MARK: Login Action
    
    @IBAction func btnLoginPressed(_ sender: UIButton) {
        if txtUserName.text == ""
        {
            //Call UIView extension method
            self.view.showToast(toastMessage: "Please Enter Username,beacuse it is necessary to add For getting logged in.", duration: 1.1)
        }
        else if txtPassword.text == ""
        {
            self.view.showToast(toastMessage: "Please Enter Password.", duration: 1.1)
        }
        else
        {
            //Do login
        }
        
    }
///////////////////////////////////////////////////
//                                            ///////
//                create Toast                ///////
//                Part 1                        ///////
//                                            ///////
///////////////////////////////////////////////////
//This is Extention of toast "it will stay outside controller"
import UIKit

//MARK: Add Toast method function in UIView Extension so can use in whole project.
extension UIView
{
    func showToast(toastMessage:String,duration:CGFloat)
    {
        //View to blur bg and stopping user interaction
        let bgView = UIView(frame: self.frame)
        bgView.backgroundColor = UIColor(red: CGFloat(255.0/255.0), green: CGFloat(255.0/255.0), blue: CGFloat(255.0/255.0), alpha: CGFloat(0.6))
        bgView.tag = 555
        
        //Label For showing toast text
        let lblMessage = UILabel()
        lblMessage.numberOfLines = 0
        lblMessage.lineBreakMode = .byWordWrapping
        lblMessage.textColor = .white
        lblMessage.backgroundColor = .black
        lblMessage.textAlignment = .center
        lblMessage.font = UIFont.init(name: "Helvetica Neue", size: 17)
        lblMessage.text = toastMessage
        
        //calculating toast label frame as per message content
        let maxSizeTitle : CGSize = CGSize(width: self.bounds.size.width-16, height: self.bounds.size.height)
        var expectedSizeTitle : CGSize = lblMessage.sizeThatFits(maxSizeTitle)
        // UILabel can return a size larger than the max size when the number of lines is 1
        expectedSizeTitle = CGSize(width:maxSizeTitle.width.getminimum(value2:expectedSizeTitle.width), height: maxSizeTitle.height.getminimum(value2:expectedSizeTitle.height))
        lblMessage.frame = CGRect(x:((self.bounds.size.width)/2) - ((expectedSizeTitle.width+16)/2) , y: (self.bounds.size.height/2) - ((expectedSizeTitle.height+16)/2), width: expectedSizeTitle.width+16, height: expectedSizeTitle.height+16)
        lblMessage.layer.cornerRadius = 8
        lblMessage.layer.masksToBounds = true
        lblMessage.padding = UIEdgeInsets(top: 4, left: 4, bottom: 4, right: 4)
        bgView.addSubview(lblMessage)
        self.addSubview(bgView)
        lblMessage.alpha = 0
        
        UIView.animateKeyframes(withDuration:TimeInterval(duration) , delay: 0, options: [] , animations: {
            lblMessage.alpha = 1
        }, completion: {
            sucess in
            UIView.animate(withDuration:TimeInterval(duration), delay: 8, options: [] , animations: {
                lblMessage.alpha = 0
                bgView.alpha = 0
            })
            bgView.removeFromSuperview()
        })
    }
}
extension CGFloat
{
    func getminimum(value2:CGFloat)->CGFloat
    {
        if self < value2
        {
            return self
        }
        else
        {
            return value2
        }
    }
}

//MARK: Extension on UILabel for adding insets - for adding padding in top, bottom, right, left.

extension UILabel
{
    private struct AssociatedKeys {
        static var padding = UIEdgeInsets()
    }
    
    var padding: UIEdgeInsets? {
        get {
            return objc_getAssociatedObject(self, &AssociatedKeys.padding) as? UIEdgeInsets
        }
        set {
            if let newValue = newValue {
                objc_setAssociatedObject(self, &AssociatedKeys.padding, newValue as UIEdgeInsets?, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
            }
        }
    }
    
    override open func draw(_ rect: CGRect) {
        if let insets = padding {
            self.drawText(in: rect.inset(by: insets))
        } else {
            self.drawText(in: rect)
        }
    }
    
    override open var intrinsicContentSize: CGSize {
        get {
            var contentSize = super.intrinsicContentSize
            if let insets = padding {
                contentSize.height += insets.top + insets.bottom
                contentSize.width += insets.left + insets.right
            }
            return contentSize
        }
    }
}