How To Create A SwiftUI Hero Animation

Hero Animation is known to offer swift translation between the two animations or screens and they look pretty good as a UI. So, if you are looking to create one, give yourself a pat on the back and follow this article.

What Is SwiftUI?

For those who know, SwiftUI is a user interface framework created by Apple for building apps on various Apple devices. Introduced in 2019, it simplifies UI development by allowing developers to describe how the interface should look and behave in a clear way.

It works across all the operating systems like iOS, macOS, watchOS, and tvOS. Along with several other beneficial features, it offers a live preview feature using which developers can see real-time updates as they code, making it an effective tool.

As far as we are concerned with the hero animation, SwiftUI is one of the best platforms to create one. Here it is easy to make and the platform offers plenty of features to test one.

MatchedGeometryEffect

One of the major modifiers that you are going to be using in the SwiftUI animation is MatchedGeometryEffect. Want to know the reason to use this modifier is:-

View Replacement:

The modifier is particularly useful for replacing one view with another.

Changing View Properties:

It facilitates the replacement of a view’s related properties, including size, height, and color.

Animation Possibilities:

This modifier enables the creation of various animations such as flip animation, hero animation, and transition animation.

Creating The Hero Animation in SwiftUI

These are the stages that are usually followed by the developers when creating the Hero Animation:-

Launch Your Project

Follow these instructions to launch your project:-

Lunch Xcode to create a new SwiftUI project.
Choose a template that aligns with your app’s objectives and hit “Create.”

Consider these steps a groundwork for seamlessly implementing the Hero Animation.

Try To Create Your Views

The next step is to create your views. Identify the views you wish to animate—these could be images, buttons, or any other elements within your app.

Lay Your Hero Animation

The next step is to use the matchedGeometryEffect modifier. This modifier ensures that SwiftUI automatically animates the transition between the specified views. Remember to use the id parameter as it plays a crucial role in determining which views to match during the animation.

Activate Your Hero Animation

The final and last step is to run your project to witness the Hero Animation in action. Try to tap on the image seamlessly transitions between the two views and check if they provide a visually striking and engaging user experience.

Let’s Explain These Steps With An Example:-

Let’s create a simple example of a SwiftUI hero animation between a list view and a detail view. For this example, we’ll use a list of items and display details when tapping on an item.

import SwiftUI

struct ContentView: View {
    let items = ["Item 1", "Item 2", "Item 3"]

    var body: some View {
        NavigationView {
            List(items, id: \.self) { item in
                NavigationLink(destination: DetailView(item: item)) {
                    Text(item)
                }
            }
            .navigationTitle("List")
        }
    }
}

struct DetailView: View {
    let item: String

    var body: some View {
        VStack {
            Spacer()
            Text(item)
                .font(.largeTitle)
                .foregroundColor(.white)
            Spacer()
        }
        .background(Color.blue)
        .edgesIgnoringSafeArea(.all)
        .navigationBarTitle("", displayMode: .inline)
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

In this example, we have a ContentView with a list of items, and each item is a NavigationLink that navigates to the DetailView when tapped. The DetailView displays the item’s details with a background color.

Now, let’s add a hero animation to smoothly transition the item from the list to the detail view.

import SwiftUI

struct ContentView: View {
    let items = ["Item 1", "Item 2", "Item 3"]

    var body: some View {
        NavigationView {
            List(items, id: \.self) { item in
                NavigationLink(destination: DetailView(item: item)) {
                    Text(item)
                        .padding()
                        .background(
                            NavigationLink("", destination: DetailView(item: item))
                                .opacity(0)
                        )
                }
            }
            .navigationTitle("List")
        }
    }
}

struct DetailView: View {
    let item: String

    var body: some View {
        VStack {
            Spacer()
            Text(item)
                .font(.largeTitle)
                .foregroundColor(.white)
            Spacer()
        }
        .background(Color.blue)
        .edgesIgnoringSafeArea(.all)
        .navigationBarTitle("", displayMode: .inline)
        .matchedGeometryEffect(id: item, in: namespace)
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

In this updated code, we use the matchedGeometryEffect modifier in the DetailView to create a hero animation. The id parameter should be a unique identifier for the view that is being transitioned. In this case, we use the item’s name as the identifier.

When working with SwiftUI hero animations, there are a few important points to keep in mind:

Unique Identifiers:
- The id parameter in matchedGeometryEffect should be a unique identifier for the view you are transitioning. It helps SwiftUI understand which views should be matched during the transition. In the example above, we used the item’s name as a unique identifier.
Same Hierarchy:
- The views you are transitioning should be in the same hierarchy. If the views are in different hierarchies, SwiftUI might not be able to create a smooth transition between them.
Geometry Reader:
- Sometimes, using a GeometryReader can help with more complex layouts. The GeometryReader allows you to access the geometry of a parent view, which can be useful for positioning and sizing views in certain scenarios.
Namespace:
- The matchedGeometryEffect should use the same namespace for the views you want to transition. In the example, namespace is used to define the namespace for the matchedGeometryEffect. Make sure to use the same namespace in both the list view and the detail view.
Performance:
- Hero animations can be resource-intensive, especially if you have many views transitioning at the same time. Be mindful of performance implications, especially on older devices.
Conditional Matching:
- You can conditionally apply the matchedGeometryEffect based on some criteria. For example, you might want to apply the effect only when transitioning to a specific detail view, or only for certain items in a list.

**How to use SwiftUI’s matchedGeometryEffect for Seamless Animations**

SwiftUI’s matchedGeometryEffect is a powerful tool that introduces smooth and captivating animations into your app’s user interface. In this guide, we’ll explore various aspects of this animation modifier and how it can be harnessed to enhance user experience.

The Foundation: Two Views and matchedGeometryEffect

At the core of matchedGeometryEffect lies the requirement for a minimum of two views. You need two views to create animations that seamlessly transition between different elements, providing a dynamic and engaging feel to your app.

Works for Hero, Flip, and Transition

The versatility of matchedGeometryEffect extends beyond conventional animations. While commonly associated with Hero animations, you can also use it creatively for Flip and Transition animations. This flexibility allows developers like you to infuse their own creativity so that there shines a unique and personalized touch to the user interface.

Applying the Magic: ID and Namespace

To implement matchedGeometryEffect effectively, it’s crucial to understand two key components: “id” and “namespace.” The “id” parameter plays a pivotal role in correlating different views during animation.

When you provide a shared identifier, SwiftUI ensures that the views maintain their identity throughout the animation process. On the other hand, think of the “namespace” as an Animation Group – a container that encapsulates related animations. This structured approach simplifies the management of various animations within your SwiftUI project.

Identities in Motion: Correlating Views with “id”

The “id” in matchedGeometryEffect serves as the glue that ties different views together. This identifier allows SwiftUI to correlate the views, which, in turn, makes them virtually identical during the animation. It’s a powerful mechanism for ensuring that the transition between views is seamless, creating a visually appealing and cohesive user experience.

Namespace: Structuring Animations for Consistency

Understanding the concept of “namespace” is essential for structuring animations consistently. Similar to an Animation Group, a namespace in SwiftUI provides an organized container for related animations. This not only enhances the readability of your code but also streamlines the management of multiple animations within your project.

Before you Go!

The matchedGeometryEffect is like a magic tool in SwiftUI that helps smoothly transition from one view to another. It’s especially great for creating those cool hero animations that make your app look fantastic.

Even though it’s powerful, there are some details about how it works that Apple’s documentation doesn’t fully explain. We’re here to share some useful tips and insights to help you use this tool effectively in your hero animations.

Have fun experimenting with the matchedGeometryEffect, and we can’t wait to see the awesome hero animations you come up with! Feel free to play around, be creative, and enjoy the process of coding.

Thanks for reading this guide. We hope you have liked It!

How To Create A SwiftUI Hero Animation?