Working with Dates in Swift

Working with Dates in Swift

To start working with dates in iOS you must be familiar with at least these three objects: Date, DateFormatter and DateComponents.

Date struct

Date is a struct that belongs to the Foundation framework.

It represents a specific point in time independent of any calendar or time zone.

Date structure bridges to the NSDate class.

It provides methods for creating dates, comparing dates and calculating time intervals between dates. Continue reading “Working with Dates in Swift”

Remove empty rows at the end of UITableView

Removing Empty Rows from the end of UITableView

Sometimes you have a table view with very few number of rows that are not covering the whole screen height.

In that case Xcode will add extra empty rows to your table view which looks very unprofessional. Continue reading “Remove empty rows at the end of UITableView”

Custom header view from xib for UITableView

In this step by step tutorial we will create a custom header view to use in UITableView and it will be loaded from xib file.

Creating the UITableViewHeaderFooterView class and xib

1- First of all create a new Swift file and make it subclass of UITableViewHeaderFooterView and name it “DemoHeaderView” Continue reading “Custom header view from xib for UITableView”

Passing data back and forward between view controllers

I will go straight to the point and tell you how to send data back and forward in different situations.

This code was written in Swift 3

Sending data forward using Segue

If you are navigating from ViewControllerA to ViewControllerB using Segue called “toViewControllerB” then do the following steps Continue reading “Passing data back and forward between view controllers”

Working with CALayer

What is CALayer

CALayer is an object responsible for drawing and animations and it is part of Core Animation framework.

It is always used as backing store for UIViews to manage visual content but it can be also used without views.

If it was created by a view the view assigns itself as delegate for that layer and you should not change that. Continue reading “Working with CALayer”

Set, Array and Dictionary what’s the differences?

Swift provides three collection types for storing collections of values

Here we will try to show the differences between them so you can easily decide which one to use in every situation.

Array:

Array is ordered collection so you can access any element inside it using its index.

Arrays can contain duplicates. Continue reading “Set, Array and Dictionary what’s the differences?”

UIViewController lifecycle explained

UIViewController Lifecycle

In this tutorial we will explain the lifecycle of UIViewController in iOS, these methods will run in the following order:

1- init?(coder aDecoder: NSCoder)

If you are using storyboards this is where the controller is initialized, it is called one time only during the view controller lifetime.

2- loadView()

Creates the view that the controller manage, the view controller calls this method when its view property is requested but is currently nil.

This method loads or creates a view and assign it to the view property. Continue reading “UIViewController lifecycle explained”

How to change UITextField placeholder color in Swift 3 and Interface Builder

You can change UITextField placeholder color programmatically or using interface builder

Changing UITextField placeholder color in Swift 3

1- Create a new UITextField subclass and  override its

layoutSubviews() and insert in it this line of code

self.setValue(UIColor.init(red: 178/255.0, green: 34/255.0, blue: 78/255.0, alpha: 0.5), forKeyPath: "_placeholderLabel.textColor")

Continue reading “How to change UITextField placeholder color in Swift 3 and Interface Builder”

How to add underline to UITextField in Swift 3

UITextField Underlined In Swift 3

Create a custom UITexField and add this method to it then override

layoutSubviews() and call it from there

    func underlined(){
        let border = CALayer()
        let lineWidth = CGFloat(0.3)
        border.borderColor = UIColor.lightGray.cgColor
        border.frame = CGRect(x: 0, y: self.frame.size.height - lineWidth, width:  self.frame.size.width, height: self.frame.size.height)
        border.borderWidth = lineWidth
        self.layer.addSublayer(border)
        self.layer.masksToBounds = true
    }

Good to know How to change UITextField placeholder color

How to detect if application run for the first time in iOS using Swift 3

How to detect if app is running for the first time

You can detect if the application is launched for the first time using NSUserDefaults.


Just by looking for a key called “launchedBefore” for example and if its not found then the application is running for the first time.

if not found then create it.

Add the following code to didFinishLaunchingWithOptions() in AppDelegate.swift file Continue reading “How to detect if application run for the first time in iOS using Swift 3”