Show the Download Status of a File in Swift with a Progress Bar
Download Progress Bar Swift: How to Create and Customize It
Have you ever wanted to show your users how much time or data is left for downloading a file or an image in your app? If so, you might need a download progress bar. A download progress bar is a graphical indicator that displays the percentage of completion of a download operation. In this article, you will learn what a download progress bar is, why you should use it, and how to create and customize it in Swift.
Introduction
What is a download progress bar?
A download progress bar is a UI component that shows the progress of a download operation. It usually consists of two parts: a horizontal bar that fills up as the download progresses, and a label that shows the numerical value of the progress, such as 50% or 10 MB out of 20 MB. A download progress bar can also have other features, such as a cancel button, a pause button, or an error message.
download progress bar swift
Why use a download progress bar?
A download progress bar can provide several benefits for your app and your users. Here are some of them:
It can improve the user experience by providing feedback and reducing uncertainty. Users can see how much time or data is left for the download, and whether the download is successful or not.
It can increase user engagement and retention by creating anticipation and satisfaction. Users can feel more motivated and rewarded when they see the progress of their download.
It can prevent user frustration and confusion by handling errors and interruptions. Users can see if there is any problem with the download, such as network failure or low battery, and take appropriate actions.
How to create a download progress bar in Swift?
There are different ways to create a download progress bar in Swift, but one of the most common and simple ways is to use URLSession and UIProgressView. URLSession is a class that provides an API for downloading and uploading data from and to a server. UIProgressView is a class that provides a standard progress bar for iOS apps. You can use these two classes together to create a basic download progress bar in Swift.
Creating a Download Progress Bar with URLSession
Setting up the UI
To set up the UI for your download progress bar, you need to add a UIProgressView and a UILabel to your storyboard or code. You can also add other UI elements, such as buttons or images, depending on your design. For example, you can add a UIButton to start or cancel the download, and an UIImageView to display the downloaded image. You also need to create outlets and actions for your UI elements in your view controller class.
Creating a URLSession data task
To create a URLSession data task for your download operation, you need to use the URLSession class and its dataTask(with:completionHandler:) method. This method takes two parameters: an URL that specifies the location of the file or image you want to download, and a completion handler that executes when the download is finished or failed. You also need to set the delegate property of your URLSession object to self, so that you can implement the delegate methods that report the progress of the download.
Implementing the URLSession delegate methods
To implement the URLSession delegate methods that report the progress of the download, you need to conform to the URLSessionDataDelegate protocol in your view controller class. This protocol defines several methods that are called when certain events occur during the data transfer. The most important methods for your download progress bar are: - urlSession(_:dataTask:didReceive:completionHandler:): This method is called when the data task receives the initial response from the server. You can use this method to check the status code and the expected content length of the response, and to decide whether to continue or cancel the download. - urlSession(_:dataTask:didReceive:): This method is called when the data task receives a portion of data from the server. You can use this method to append the received data to a data object, and to calculate and update the progress of the download. - urlSession(_:task:didCompleteWithError:): This method is called when the data task finishes or fails. You can use this method to handle any error that occurred during the download, and to perform any final actions, such as converting the data object to an image and displaying it on the image view. Updating the progress bar value and label
To update the progress bar value and label, you need to use the UIProgressView class and its progress and progressTintColor properties. The progress property is a float value that represents the fraction of the download that is completed, ranging from 0.0 to 1.0. The progressTintColor property is a UIColor value that represents the color of the filled portion of the progress bar. You can set these properties in your URLSession delegate methods, using the DispatchQueue.main.async method to ensure that the UI updates are performed on the main thread.
Customizing the Download Progress Bar with UIProgressView
Changing the progress bar color and style
To change the progress bar color and style, you can use the UIProgressView class and its trackTintColor and progressViewStyle properties. The trackTintColor property is a UIColor value that represents the color of the unfilled portion of the progress bar. The progressViewStyle property is an enum value that represents the appearance of the progress bar, which can be either default, bar, or tinted. You can set these properties in your storyboard or code, depending on your preference.
Adding a track image and a progress image
To add a track image and a progress image, you can use the UIProgressView class and its trackImage and progressImage properties. The trackImage property is a UIImage value that represents the image that is displayed behind the progress bar. The progressImage property is a UIImage value that represents the image that is displayed on top of the progress bar. You can set these properties in your storyboard or code, depending on your preference.
Animating the progress bar changes
To animate the progress bar changes, you can use the UIProgressView class and its setProgress(_:animated:) method. This method takes two parameters: a float value that represents the new progress value, and a boolean value that indicates whether to animate the change or not. You can call this method in your URLSession delegate methods, instead of setting the progress property directly, to create a smooth transition effect.
How to create a custom download progress bar in Swift
Swift tutorial: Implementing a download progress view with URLSession
Download progress indicator with SwiftUI and Combine
Swift 5: Using ProgressHUD to show download progress
Show download progress in a circular progress bar with Swift
Using MKMagneticProgress to display download progress in Swift
How to observe the progress property of URLSessionDataTask in Swift
LinearProgressBar: A simple and elegant linear progress view for Swift
How to use ChartProgressBar to draw a chart with progress bar style in Swift
AWStepBar: A step progress UI component for Swift
How to animate a gradient progress bar with TYProgressBar in Swift
ProgressMeter: Measuring the download progress with annotations in Swift
How to use MultiProgressView to depict multiple progresses over time in Swift
ShowSomeProgress: Progress and activity indicators for iOS apps in Swift
How to use IJProgressView to show a simple progress view in Swift
AMProgressBar: An elegant progress bar for your iOS apps in Swift
How to calculate the download progress of a file in Swift
How to use NSURLSessionDownloadDelegate to get the download progress status in Swift
How to update the UI with the download progress using dispatch_async in Swift
How to use interface builder designable and inspectable properties for progress bars in Swift
How to create a segmented progress view like Instagram in Swift
How to use core graphics to draw a custom progress bar in Swift
How to use KVO to observe the fractionCompleted property of Progress in Swift
How to use UIProgressView to show the download progress in Swift
How to customize the appearance and animation of progress bars in Swift
How to use Alamofire to download files and show the progress in Swift
How to use Firebase Storage to upload and download files with progress bars in Swift
How to use SDWebImage to download images and show the progress in Swift
How to use Kingfisher to download images and show the progress in Swift
How to use Nuke to download images and show the progress in Swift
How to use MBCircularProgressBar to show circular progress bars in Swift
How to use YLProgressBar to show custom progress bars in Swift
How to use GTProgressBar to show gradient tinted progress bars in Swift
How to use RPCircularProgress to show circular and indeterminate progress indicators in Swift
How to use FlexibleSteppedProgressBar to show a stepped progress bar in Swift
How to use KYCircularProgress to show circular progress bars with gradient colors in Swift
How to use M13ProgressSuite to show various types of progress indicators in Swift
How to use DACircularProgress to show circular progress views with UIKit dynamics in Swift
How to use KDCircularProgress to show circular progress views with animations in Swift
How to use LDProgressView to show flat or gradient style progress views in Swift
How to use UICircularProgressRingView to show circular pr