How to use UI Sliders in iOS?

iOS UI Sliders

In iOS slider is a horizontal bar with thumb control, by using this we can slide between minimum and maximum value. Generally, we use sliders to increase or decrease value like adjust screen brightness level or change the volume of speaker like as shown below

We can use Sliders in our iOS applications by adding UISlider class reference.

Now we will see how to use iOS UI sliders in our iOS applications with example.

Create iOS UI Sliders App in Swift

To create new project in iOS open Xcode from /Applications folder directory. Once we open Xcode the welcome window will open like as shown below. In welcome window click on the second option “Create a new Xcode Project” or choose File à New à Project.

After selecting “Create a new Xcode project” a new window will open in that we need to choose template.

The new Xcode window will contain several built-in app templates to implement common type of iOS apps like page based apps, tab-based apps, games, table-view apps, etc. These templates are having pre-configured interface and source code files. 

For this iOS Slider example, we will use most basic template “Single View Application”. To select this one, Go to the iOS section in left side à select Application à In main area of dialog select “Single View Application” and then click on next button like as shown below.

After click Next we will get window like as shown below, in this we need to mention project name and other details for our application.

Product Name: “Slider in iOS”

The name whatever we enter in Product Name section will be used for the project and app.

Organization Name: “Tutlane”

You can enter the name of your organization or your own name or you can leave it as blank.

Organization Identifier: “com.developersociety”

Enter your organization identifier in case if you don't have any organization identifier enter com.example.

Bundle Identifier: This value will generate automatically based on the values we entered in Product Name and Organization Identifier.

Language: “Swift”

Select language type as “Swift” because we are going to develop applications using swift.

Devices: “Universal”

Choose Devices options as Universal it means that one application is for all apple devices in case if you have any specific requirement to run app only for iPad then you can choose the iPad option to make your application restricted to run only on iPad devices.

Use Core Data: Unselected

This option is used for database operations. In case if you have any database related operations in your application select this option otherwise unselect the option.

Include Unit Tests: Unselected

In case if you need unit tests for your application then select this option otherwise unselect it.

Include UI Tests: Unselected

In case if you need UI tests for your application then select this option otherwise unselect it.

Once you finished entering all the options then click on Next button like as shown below.

Once we click on Next button new dialog will open in that we need to select the location to save our project. Once you select the location to save project then click on Create button like as shown below

After click on Create button the Xcode will create and open a new project. In our project Main.storyboard and ViewController.swift are the main files which we used to design app user interface and to maintain source code. 

Main.storyboard - Its visual interface editor and we will use this file to design our app user interface 

ViewController.swift - It contains source code of our application and we use this file to write any code related to our app.

Now in project select Main.storyboard file the Xcode will open visual interface editor like as shown below.

Now select ViewController.swift file in your project that view will be like as shown below.

Add iOS UI Controls to View in Swift

Now we will add controls to our application for that open Object Library. The Object Library will appear at the bottom of Xcode in right side. In case if you don't find Object library, click on the button which is at the third position from the left in the library selector bar like as shown below. (Alternatively you can choose View à Utilities à Show Object Library).

As we discussed our user interface will be in Main.storyboard file so open Main.storyboard file. Now in Object library search for the Slider in Filter field then drag and drop the Slider control into Main.storyboard ViewController same way we need to add one button control to ViewController like as shown below

Connect iOS UI Controls to Code in Swift

Now we will make connection between controls and ViewController.Swift code for that click on assistant button (overlap circle) in Xcode toolbar right side corner like as shown below

To map the controls, press Ctrl button in keyboard and drag the slider and button controls from canvas interface and drop into ViewController.swift file like as shown below

Once we add controls to ViewController.swift file then write the custom code to show the slider value in button control while moving between minimum and maximum values. Once we write all required functionality our ViewController.swift file code should be like as shown below.

//  ViewController.swift

//  Slider in iOS

//  Created by Tutlane on 10/08/2016.

//  Copyright © 2016 Tutlane. All rights reserved.

import UIKit

class ViewController: UIViewController {

@IBOutlet weak var slider: UISlider!

@IBOutlet weak var buttonl: UILabel!

@IBAction func sliderValueChange(sender: AnyObject) {

let currentValue = Int(slider.value)

buttonl.text = "\(currentValue)"

}

override func viewDidLoad() {

super.viewDidLoad()

// Do any additional setup after loading the view, typically from a nib.

}

override func didReceiveMemoryWarning() {

super.didReceiveMemoryWarning()

// Dispose of any resources that can be recreated.

}

}

Now we will run and check the output of application. To run application, select the required simulator (Here we selected iPhone 6s Plus) and click on Play button, located at the top-left corner of the Xcode toolbar like as shown below.

Output of iOS Sliders App in Swift

Following is the result of iOS Sliders application. Now slide the slider from left to right or right to left the respective value will show in button control like as shown below.

This is how we can use iOS ui sliders in swift to slide the value between minimum and maximum range values using thumb control in horizontal bar.