In this blog, we will draw out a detailed differentiation between Jetpack Compose and XML, both of which are used for creating Android apps. As app development of all kinds undergoes continuous evolution and growth, modern UI development has become essential. Jetpack Compose and XML play an impactful role in this ever-transforming world of app development. 

We will compare both methods and analyze the distinct strengths and capabilities of Jetpack Compose with regard to UI development. We will also make use of a list view-based practical example to show the direct advantages of using Android Jetpack and how it can be beneficial in modern UI development.

What is Jetpack Compose?

Jetpack Compose is a new tool for making Android apps that look and feel great. It simplifies the process of building interactive and dynamic user interfaces by employing a straightforward and clear method to describe the desired interface appearance. Instead of writing complex XML code, you can use Kotlin functions to create UI components in a concise and easily comprehensible manner. Plus, you get to see your changes instantly with real-time previews, and there are built-in features for handling how things move and change on the screen. It's a modern and enjoyable way to develop Android apps!

Jetpack Compose was first launched by Google in May 2019 at Google I/O. Ever since its introduction, this approach has become quite popular among the developers' community and its utilization has increased. Its latest version 1.5.0 was released on August 9, 2023.

What are XML views?

Traditional XML views have been the longstanding method for crafting user interfaces in Android apps. By defining layouts, visual styles, and behaviors through XML files, developers have the flexibility to customize UI elements. Despite requiring more manual coding, this reliable approach remains widely used in Android app development. 

XML-based layouts were launched during the release of Android in 2008. They quickly gained popularity for designing user interfaces. The Android ecosystem has seen many critical updates and improvements since its release and XML has acted as one of the pillars during this phase by staying relevant. Its utilization in various applications has also been continuous and constant.

XML plays an important role in defining the visual structure of a user interface. It lays down the structuring and defines the properties of UI elements like Text Views, Image Views, Buttons, and many more. XML keeps the layout information separate from the code logic. By doing this, XML is able to support easy collaboration between developers and designers and it also enables fast upgradation or changes in the design process.

However, even with extensive usage, XML faces a few limitations. Android apps have become more complicated, and their features have also increased over time. This results in the XML code becoming bulky and extensive, leading to an increase in maintenance efforts proportionally. Managing of intricate UI interactions and animations also becomes complex and requires manual efforts as well.

Jetpack Compose vs. XML views: the differences

In this comparison, we explore the key differences between these two methodologies. Discover how Android Jetpack Compose revolutionizes UI development.

Declarative UI

Jetpack Compose utilizes a declarative approach, where you express the desired UI state, and the framework manages its rendering. In contrast, the XML view approach is imperative, requiring manual manipulation of view hierarchies and state changes.

Simplified UI Development

Jetpack Compose offers a more concise and intuitive way to build UIs with less boilerplate code. It leverages Kotlin's language features and allows you to create UI components as functions, resulting in more readable and maintainable code. Traditional XML views involve writing XML files and using separate Java/Kotlin code to handle logic and interactions.

Real-time Preview

Jetpack Compose has an amazing real-time preview feature that allows you to instantly see any changes you make to the user interface. You can even check how the UI interacts using the "Interactive Mode," which makes it easier to refine and improve your designs. On the other hand, when using XML, you can preview the UI, but to test the interactions, you'll need to run the app.

Reactive Programming

Jetpack Compose embraces reactive programming principles, allowing you to easily manage UI state and handle UI updates based on data changes. XML requires manual management of view state and event handling.

Animations and Transitions

Jetpack Compose offers a simplified way to create animations and transitions, with built-in support for common animations. XML views require additional XML attributes and separate animation files to achieve similar effects.

Performance and Efficiency

Compose leverages a highly optimized rendering engine, which can result in better UI performance and efficiency compared to XML views. Composes state management also helps reduce unnecessary UI updates and improves overall performance.

Ecosystems and Futureproofing

Jetpack Compose is part of the official Android Jetpack library and is actively supported by Google. It benefits from regular updates, bug fixes, and new features. While XML views will still be supported, Google's focus is on advancing Jetpack Compose, making it a future-proof choice for UI development.

Also read: Accelerating Development through Reusable Components for Enhanced Efficiency

Jetpack Compose vs. XML: architecture

Developers have a variety of options in terms of architectural frameworks when they initiate the design of user interfaces in Android app development. The two most common choices here are Jetpack Compose and XML architecture. Both approaches have a number of advantages and disadvantages that need to be considered when zeroing in on one because they have a huge impact on the overall development process, code maintainability, and user experience.

Jetpack Compose architecture

Jetpack Compose involves a comparatively more modern, declarative, and composable architecture that ensures UI components definition during development with the use of simple and brief Kotlin functions. The framework is majorly centered on the notion of constructing UI elements as reusable and independent building blocks.

In Jetpack Compose, UI is defined as a function of the app. This means that the UI automatically updates its features in proportion to any changes in the state. The major point to be noted is that it only updates the affected parts and not the entire framework. This kind of reactive ability in the UI development framework makes the management of UI state convenient and guarantees that the UI framework always showcases the current state of the app.

Jetpack Compose also simplifies the management of UI interactions and handling of difficult animations. Developers are also able to create customized functions to summarize specific UI behaviors. This makes the codebase more integrated and sustainable. This architectural style also syncs well with reactive programming principles and permits cleaner and more testable code.

XML architecture

XML architecture is used with traditional XML. Jetpack Compose differs majorly as it follows an imperative and hierarchical approach to define UI layouts. XML files serve as outlines for the UI, and they lay down the structuring and properties of individual UI components. The XML-based approach depends majorly on view hierarchies, where views are put close together to create the overall UI structure.

XML architecture requires manual efforts for the management of UI state and interaction handling. This increases the complexity and length of code specifically in larger apps with elaborate UIs. Developers need to maintain a clear approach to managing view state changes and updates because they are more susceptible to errors and make the code more difficult to maintain.

Also Read: Android Instant Apps: Resolving App Non-Installation for Users

A closer look at the list view case

When it comes to building user interfaces in Android apps, the list view is a fundamental component that allows for the efficient display of data in a scrollable format. Here in this section, we'll take a closer look at the List View case and explore two popular approaches for implementing it.

List with the XML view approach

In the traditional way of building dynamic lists in Android, developers had to deal with complicated and repetitive code. They had to handle RecyclerViews, adapters, and view holders to display data correctly. However, this approach often leads to messy and confusing code, making it hard to understand and maintain. To demonstrate the difficulties involved, let's take a look at how a book list would typically be created using this traditional approach.

Example:

First, you'll need to define your book item layout (book_item.xml) that represents the individual book view in the list:

1<!-- book_item.xml -->
2<LinearLayout
3    xmlns:android="http://schemas.android.com/apk/res/android"
4    android:layout_width="match_parent"
5    android:layout_height="wrap_content"
6    android:orientation="vertical"
7    android:padding="16dp">
8
9    <TextView
10        android:id="@+id/bookTitleTextView"
11        android:layout_width="wrap_content"
12        android:layout_height="wrap_content"
13        android:textSize="16sp"
14        android:textStyle="bold"/>
15
16    <TextView
17        android:id="@+id/bookAuthorTextView"
18        android:layout_width="wrap_content"
19        android:layout_height="wrap_content"
20        android:textSize="14sp"/>
21</LinearLayout>

Next, create an adapter class (Booklist Adapter) that extends RecyclerView. Adapter to read and manage the book data:

1public class BookListAdapter extends RecyclerView.Adapter<BookListAdapter.BookViewHolder> {
2    private List<Book> bookList;
3
4    public BookListAdapter(List<Book> bookList) {
5        this.bookList = bookList;
6    }
7
8    @NonNull
9    @Override
10    public BookViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
11        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.book_item, parent, false);
12        return new BookViewHolder(view);
13    }
14
15    @Override
16    public void onBindViewHolder(@NonNull BookViewHolder holder, int position) {
17        Book book = bookList.get(position);
18        holder.bookTitleTextView.setText(book.getTitle());
19        holder.bookAuthorTextView.setText(book.getAuthor());
20    }
21
22    @Override
23    public int getItemCount() {
24        return bookList.size();
25    }
26
27    public class BookViewHolder extends RecyclerView.ViewHolder {
28        TextView bookTitleTextView;
29        TextView bookAuthorTextView;
30
31        public BookViewHolder(@NonNull View itemView) {
32            super(itemView);
33            bookTitleTextView = itemView.findViewById(R.id.bookTitleTextView);
34            bookAuthorTextView = itemView.findViewById(R.id.bookAuthorTextView);
35        }
36    }
37}

Finally, you can use the adapter in your activity or fragment to display the book list

1public class BookListActivity extends AppCompatActivity {
2    private RecyclerView bookRecyclerView;
3    private BookListAdapter bookListAdapter;
4    private List<Book> bookList;
5
6    @Override
7    protected void onCreate(Bundle savedInstanceState) {
8        super.onCreate(savedInstanceState);
9        setContentView(R.layout.activity_book_list);
10
11        // Assuming you have initialized and populated the bookList
12
13        bookRecyclerView = findViewById(R.id.bookRecyclerView);
14        bookRecyclerView.setLayoutManager(new LinearLayoutManager(this));
15        bookListAdapter = new BookListAdapter(bookList);
16        bookRecyclerView.setAdapter(bookListAdapter);
17    }
18}

List with Jetpack Compose

Jetpack Compose brings a refreshing change to Android development with its straightforward and easy-to-understand approach. It allows us to create user interface components using a simple function-based approach. Now, let's explore how we can harness the power of Jetpack Compose to effortlessly create a dynamic book list.

Example

First, create a composable function BookList that takes a list of books as a parameter and displays them:

1@Composable
2fun BookList(books: List<Book>) {
3    LazyColumn {
4        items(books) { book ->
5            BookItem(book)
6        }
7    }
8}
9
10@Composable
11fun BookItem(book: Book) {
12    Column(
13        modifier = Modifier
14            .fillMaxWidth()
15            .padding(16.dp)
16    ) {
17        Text(text = book.title, fontWeight = FontWeight.Bold, fontSize = 16.sp)
18        Text(text = book.author, fontSize = 14.sp)
19    }
20}

In the code above, BookList is a composable function that uses Lazy Column to efficiently handle large lists. It uses the items function to iterate over the list of books and calls the BookItem composable for each book.

The BookItem composable represents the layout of an individual book item. It uses the Column composable to arrange the Text composable components that display the book's title and author.

To display the book list in your activity or fragment, use the setContent function:

1class MainActivity : AppCompatActivity() {
2    private val bookList = listOf(
3        Book("Title 1", "Author 1"),
4        Book("Title 2", "Author 2"),
5        Book("Title 3", "Author 3")
6    )
7
8    override fun onCreate(savedInstanceState: Bundle?) {
9        super.onCreate(savedInstanceState)
10        setContent {
11            BookList(books = bookList)
12        }
13    }
14}

In this example, MainActivity sets the content view using setContent and directly calls the BookList composable, passing in the bookList data.

As you can see, the Jetpack Compose implementation is much simpler and more concise compared to the traditional approach. You don't have to deal with adapters, view holders, or complex XML layouts. Instead, you define composable functions that represent your UI components and compose them together to build the UI hierarchy.

Jetpack Compose leverages Kotlin's concise and expressive syntax, allowing you to create dynamic and interactive UIs with minimal boilerplate code.

With Jetpack Compose, building a book list becomes a straightforward and enjoyable process, empowering you to focus on the actual UI design and functionality of your app.

Also Read: Creating an Android App to Scaring Away Pigeons with ML Kit

Use cases and applicability

Both Jetpack Compose and traditional XML Views work well in different scenarios. Therefore, it is important to understand their practical use circumstances and their utilization in the same for making any decision about their implementation in the Android app development process. In this section, we will discover various situations where one outshines the other and may help the developers in making a good sustainable choice between both:

Also read: Evaluating App Performance: Native Android vs. Flutter Development

Code Examples: Direct Comparisons

To understand the key differences between Jetpack Compose and XML, below are some code snippets that show the contrast in verbosity, boilerplate code, and the declarative vs imperative approaches.

1. Button with a Click Listener

XML Approach:

1<Button
2    android:id=”@+id/myButton”
3    android:layout_width=”wrap_content”
4    android:layout_height=”wrap_content”
5    android:text=”Click Me” />
6
7val myButton: Button = findViewById(R.id.myButton)
8myButton.setOnClickListener {
9    // Handle button click
10}

Jetpack Compose Approach:

1@Composable
2fun MyButton() {
3    Button(onClick = { /* Handle button click */ }) {
4        Text(text = “Click Me”)
5    }
6}

2. TextView with Dynamic Content

XML Approach:

1<TextView
2    android:id=”@+id/myTextView”
3    android:layout_width=”wrap_content”
4    android:layout_height=”wrap_content”
5    android:text=”Hello, World!” />
6
7val myTextView: TextView = findViewById(R.id.myTextView)
8myTextView.text = “Updated Text”

Jetpack Compose Approach:

1@Composable
2fun MyTextView() {
3    var text by remember { mutableStateOf(“Hello, World!”) }
4
5    Text(text = text)
6}

3. Linear Layout (Vertical) with Multiple Views

XML Approach:

1<LinearLayout
2    android:layout_width=”match_parent”
3    android:layout_height=”wrap_content”
4    android:orientation=”vertical”>
5
6    <TextView
7        android:layout_width=”wrap_content”
8        android:layout_height=”wrap_content”
9        android:text=”Text 1″ />
10
11    <TextView
12        android:layout_width=”wrap_content”
13        android:layout_height=”wrap_content”
14        android:text=”Text 2″ />
15</LinearLayout>

Kotlin:

1val myLinearLayout: LinearLayout = findViewById(R.id.myLinearLayout)
2
3val textView1 = TextView(context).apply {
4    text = “Text 1”
5}
6
7val textView2 = TextView(context).apply {
8    text = “Text 2”
9}
10
11myLinearLayout.addView(textView1)
12myLinearLayout.addView(textView2)

Jetpack Compose Approach:

1@Composable
2fun MyLinearLayout() {
3    Column {
4        Text(text = “Text 1”)
5        Text(text = “Text 2”)
6    }
7}

4. RecyclerView vs LazyColumn

XML Approach (RecyclerView):

1<androidx.recyclerview.widget.RecyclerView
2    android:id=”@+id/recyclerView”
3    android:layout_width=”match_parent”
4    android:layout_height=”match_parent” />
5
6val recyclerView: RecyclerView = findViewById(R.id.recyclerView)
7recyclerView.layoutManager = LinearLayoutManager(this)
8recyclerView.adapter = MyAdapter(myList)

Jetpack Compose Approach (LazyColumn):

1@Composable
2fun MyLazyColumn(myList: List<String>) {
3    LazyColumn {
4        items(myList) { item ->
5            Text(text = item)
6        }
7    }
8}

5. ImageView with Rounded Corners

XML Approach:

1<ImageView
2    android:id=”@+id/imageView”
3    android:layout_width=”wrap_content”
4    android:layout_height=”wrap_content”
5    android:src=”@drawable/my_image”
6    android:scaleType=”centerCrop” />
7
8val imageView: ImageView = findViewById(R.id.imageView)
9Glide.with(this)
10    .load(imageUrl)
11    .apply(RequestOptions().transform(RoundedCorners(20)))
12    .into(imageView)

Jetpack Compose Approach:

1@Composable
2fun MyImageView() {
3    Image(
4        painter = painterResource(R.drawable.my_image),
5        contentDescription = null,
6        modifier = Modifier
7            .size(128.dp)
8            .clip(RoundedCornerShape(20.dp)),
9        contentScale = ContentScale.Crop
10    )
11}

Jetpack Compose vs XML: Performance

Jetpack Compose utilizes a highly optimized rendering engine for performance. It is specifically curated for modern UI requirements. This framework is assertive in nature and reduces irrelevant re-renders by categorically updating parts of the UI affected by state changes, thus enhancing overall efficiency.

On contrast to this, XML-based layouts seemingly require more manual intervention to ascertain performance efficacy. However, even with these additional efforts, they are still reliable. But as the complexity of the UI increases, maintaining consistent high performance with XML can be difficult to navigate. This may also be due to the critical nature of handling view hierarchies, which can substantially increase processing time as well as cause inconvenience in managing state changes.

Performance Metrics Comparison

Memory Usage: Jetpack Compose requires less memory in comparison to XML. Unlike the extensive view hierarchies used in XML, Jetpack Compose is able to efficiently conduct state management and rendering mechanisms in a simplified way.

Rendering Speed: The rendering times of Jetpack Compose are faster, especially for dynamic content. This is majorly due to its optimized rendering engine that only updates affected UI components.

Responsiveness: Jetpack Compose has a reactive programming model which facilitates smoother and seamless interactions. The UI updates here are more effective in comparison to the manual state management required in XML views.

Key Areas Where Jetpack Compose Excels in Performance:

Efficient Rendering: Updates happen only in the affected UI components, thus leading to lower resource usage.

State Management: There's a provision for built-in support for reactive programming, which efficiently reduces the complexity of managing UI changes and also improves responsiveness.

Animations: Jetpack Compose catalyzes smoother handling of complex animations and that too with a lesser number of performance bottlenecks, in comparison to XML, which requires additional files and configurations for producing similar results.

Memory Usage & CPU Comparison: Jetpack Compose vs XML

The optimization of Jetpack Compose allows it to handle complex UI effectively by lowering down irrelevant UI recompositions and updates. It reduces memory usage and CPU consumption and is able to garner much better outcomes compared to traditional XML-based layouts.

Recomposition Efficiency: In Jetpack Compose, updates happen only in the parts of the UI affected by state changes, whereas in XML layouts, the larger parts of the view hierarchy may need to be redrawn.

Fewer View Hierarchies: XML often includes thoroughly formed view hierarchies. Jetpack Compose, on the other hand, utilizes a flat, lightweight component tree.

Render Optimization: Jetpack Compose makes UI rendering much more efficient. This is majorly due to the fact that its optimized rendering engine avoids traditional view management overhead.

Jetpack Compose: Adaptive Layouts & Responsiveness

Jetpack Compose curates simplified versions of adaptive layouts compatible for varied screen sizes and orientations. It also provides inherent support for responsiveness, allowing the UI to adjust across different devices like phones, tablets, foldables, and Chromebooks.

Modifiers: Compose uses Modifiers to adjust layouts, thus enabling developers to define UI behavior for varied screen sizes.

Constraint Layout: The Compose version of Constraint Layout allows easily adjustable complex UI designs based on device screen dimensions.

Box With Constraints: This composable helps in attributing adaptability of UI to constraints by providing the available size, allowing customized layouts (e.g., different layouts for larger screens).

With adaptive layouts, Compose ensures that the user is able to have an optimized experience on various devices while using the app. It also supports multi-window mode and effectively handles foldable screens, making UI management scalable and future-proof.

Is Jetpack Compose Better Than XML?

There is a notion that Jetpack Compose is better than XML. However, this cannot be given blanket approval as much depends on your project. However, it is definitely true that there are many reasons why many developers are now migrating to Jetpack Compose.

Ease of Use and Readability

Jetpack Compose makes the development process simpler by decreasing the amount of boilerplate code. Its declarative syntax, clubbed together with Kotlin’s expressive language features, makes it convenient for developers to write, read, and maintain UI code. However, with XML, there is a frequent need to manage separate layout files and accompanying Kotlin/Java code, which can lead to complexity.

Reactivity

Compose is structured on the principles of reactive programming. UIs are updated dynamically based on changes in state. This means that developers don’t have to manually manage view updates.  with XML, however, manual tracking is required along with manual updating of UI elements when the underlying data changes. This can introduce bugs and slow down overall development.

Community and Future Support

Compose is definitely becoming a popular choice with its growing community and active updates. Due to this, it is well-supported for upcoming projects as well. XML is a convenient option for legacy systems and simpler apps but does not have much to offer in terms of any focus or efforts for future development.

Customization and Flexibility

There is a greater degree of customization that is possible with Compose through its Composable and modifiers. In XML, while tailored views are possible, they frequently require significantly more hard work in the backend. Compose simplifies the structuring of custom components, making UI design more flexible and adaptive.

Declarative Syntax vs Imperative Syntax

Jetpack Compose undertakes an assertive approach where developers describe what the UI should look like, and the remaining part is handled by the framework. This is in contrast to XML. A critical approach, where the developer needs to explain both the UI and the steps to modify it, adds an extra layer of complexity.

In summary, Jetpack Compose offers diverse advantages over XML, especially in terms of performance, flexibility, convenience, adaptability, and ease of use, thus making it a preferred choice for modern Android development.

Conclusion

Jetpack Compose completely transforms how we create user interfaces in Android apps, and its advantages become particularly clear when dealing with lists. Through our example of a book list, we have demonstrated how Jetpack Compose simplifies the entire process and boosts developer efficiency. With its declarative approach, elimination of excessive code, and robust state management capabilities, Jetpack Compose undoubtedly represents the future of Android UI development. 

To further explore Jetpack Compose and its capabilities, check out these Jetpack Compose Samples.

If you are considering implementing Jetpack Compose into your app projects, our specialized Android app developers at Aubergine Solutions can guide you every step of the way. Whether you want to optimize your existing app's UI, create a new dynamic interface, or explore the full potential of Jetpack Compose, we can help deliver engaging and innovative user interfaces that captivate your audience.