UIImage from a UIColor

Many time graphic team are very busy and they are not able to provide single color image or background for my controller. So, I do google and found  Below code help me to convert UIColor to UIImage.

In Objective-c 

+ (UIImage *)imageFromColor:(UIColor *)color {
    CGRect rect = CGRectMake(0, 0, 1, 1);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetFillColorWithColor(context, [color CGColor]);
    CGContextFillRect(context, rect);
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return image;
}

UIImage *img = [YourClassName imageFromColor:[UIColor blueColor]];

In Swift 2.0

extension UIImage {
    static func fromColor(color: UIColor) -> UIImage {
        let rect = CGRect(x: 0, y: 0, width: 1, height: 1)
        UIGraphicsBeginImageContext(rect.size)
        let context = UIGraphicsGetCurrentContext()
        CGContextSetFillColorWithColor(context, color.CGColor)
        CGContextFillRect(context, rect)
        let img = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return img
    }
}  

let img = UIImage.fromColor(.blueColor())

For alpha replace 

UIGraphicsBeginImageContext(rect.size);

With

UIGraphicsBeginImageContextWithOptions(rect.size, NO, 0);

Using a dispatch_once create a Singleton model in Swift

The traditional Objective-C approach in Swift to create a Singleton model.

One of the toughest issues to debug is the one created by the multiple instances of a class which manages the state of a single resource. It is highly desirable if we can use some Design Pattern to control the access to that shared resource. The Singleton pattern fits the bill perfectly to solve this scenario; by wrapping a singleton class around this problem ensures that there will be only one instance of the class at any given time. A most common and clichéd example for a singleton class is the one used for logging purposes where the whole application needs only one logger instance at anytime

If you opt for the lazy instantiation paradigm, then the singleton variable will not get memory until the property or function designated to return the reference is first called. This type of instantiation is very helpful if your singleton class is resource intense.

class Global: NSObject {

    var arrayDaysName: NSMutableArray! = []

    class var sharedInstance : Global {

        struct Static {

            static var onceToken : dispatch_once_t = 0

            static var instance : Global? = nil

        }

        dispatch_once(&Static.onceToken) {

            Static.instance = Global()

        }

        return Static.instance!

    }

}

How to use?, It simple

Global.sharedInstance.arrDaysForecast = //Do what you want

Create Custom Cell Using XIB With Protocol(Call back method) in swift

I will show you how to customize table view cells by using static xib and by subclassing UITableViewCell in Swift.

Create a Empty project and next create a subclass with xib named by CustomTableCell.

In next three screen follow the code(don't forgot delegate 'CustomTableCellDelegate') and design the xib.

Also create a uibutton action

In your viewcontroller implement cell delegate and tableview datasource and delegate also

and follow the screens

if you create a cell without Register cell close 'option 1' and open 'option 2' codes

And in viewcontroller xib 

every thing is done now just run your project

Create Custom Cell Using XIB With Protocol(Call back method)

I will show you how to customize table view cells by using static xib and by subclassing UITableViewCell. 

First, create a new project. In Xcode Click File ->New ->Project ->Single View Application

Set up the rest as in the picture below and click Next (I put project name CellProject)

The next step is to create a custom UITableViewCell. Right-click your project name node in the Project Navigation view and choose ->New File ->Cocoa Touch Class.

Set Class for you cell (I put here CustomTableViewCell) and must be subclass to UITaleViewCell and conform check Also create XIB file option.

And also I create protocol for button action it gave me callback on my view when I click any button.

Be sure to have Outlet type of the connection selected. Name the property valueField

We are going to create a value object based on NSObject class for hold data. In my case I am using User model.

Now, In ViewController class and stroyboard and I add all the necessary like, tableview add table view delegate and custom cell delegate. And add a dummy data method. and run the app

And finally you got this :)