10 Android Jetpack Compose Best Practices

Android Jetpack Compose is a modern toolkit for building native Android UI. It simplifies and accelerates UI development on Android with less code, powerful tools, and intuitive Kotlin APIs.

If you’re new to Android Jetpack Compose, you may be wondering what best practices you should follow when developing with it. In this article, we’ll discuss 10 Android Jetpack Compose best practices that you should consider when building your app. We’ll cover topics such as code organization, performance optimization, and testing.

1. Use the Compose DSL for creating and managing UI components

The Compose DSL is a declarative programming language that allows developers to create and manage UI components in an intuitive way. It provides a concise syntax for defining the structure of a user interface, making it easier to read and understand than traditional imperative code. This makes it much simpler to maintain and modify existing code, as well as quickly develop new features.

Compose also offers several advantages over other approaches to creating UIs. For example, its composable functions allow developers to easily reuse components across multiple screens, reducing development time and complexity. Additionally, Compose’s built-in state management system helps ensure that changes made to one component are automatically reflected in all related components, eliminating the need for manual synchronization.

Furthermore, Compose simplifies testing by allowing developers to write unit tests directly against their UI components. This eliminates the need to manually test each individual element, saving both time and effort. Finally, Compose supports hot reloading, which enables developers to instantly preview changes without having to restart the app.

2. Leverage state management with State objects and remember to scope them correctly

State objects are a way to store and manage the state of your application. They allow you to keep track of data that is used throughout your app, such as user preferences or UI states. By using State objects, you can ensure that any changes made to the state will be reflected in all parts of your app that use it. This makes it easier to maintain consistency across different screens and components.

When using Android Jetpack Compose, it’s important to remember to scope your State objects correctly. Scoping refers to how the State object is defined and where it can be accessed from. For example, if you define a State object at the top level of your app, then it can be accessed from anywhere within the app. However, if you define a State object inside a specific component, then it can only be accessed from within that component. This helps to prevent unintended side effects by ensuring that each component has its own isolated state.

It’s also important to note that State objects should not be mutated directly. Instead, they should be updated through setters provided by the State object itself. This ensures that any changes made to the state are properly tracked and propagated throughout the app.

3. Utilize composable functions for reusability and modularity in your codebase

Composable functions are a way to break down complex UI into smaller, reusable components. This makes it easier to maintain and update code over time, as well as making the code more readable and understandable for other developers. By breaking down complex UI into composable functions, you can create modular components that can be reused in different parts of your app.

Using composable functions also helps with scalability. As your app grows, so does the complexity of its UI. Composable functions allow you to scale up your UI without having to rewrite large chunks of code. You can simply add new composable functions or modify existing ones to fit the needs of your app.

Additionally, using composable functions allows you to take advantage of Jetpack Compose’s built-in state management capabilities. With composable functions, you can easily manage the state of your UI elements, such as visibility, text content, and color. This makes it easy to keep track of changes in your UI and ensure that everything is always up to date.

Furthermore, composable functions make it easier to test your code. Since each function is self-contained, you can easily isolate any issues and quickly identify where the problem lies. This makes debugging much simpler and faster.

4. Leverage @Composable functions to create custom components

@Composable functions are a way to create custom components in Jetpack Compose. They allow developers to define their own UI elements, which can be used as building blocks for larger compositions. This makes it easier to reuse code and keep the overall structure of an app consistent.

The @Composable annotation is what tells the compiler that this function should be treated as a composable component. It also allows the developer to specify parameters that will be passed into the function when it is called. These parameters can be used to customize the behavior or appearance of the component. For example, if you have a button component, you could pass in different colors or text labels to change how it looks.

When creating a custom component with @Composable functions, there are several benefits. Firstly, they make it easy to break down complex UIs into smaller, more manageable pieces. This helps to reduce complexity and improve readability. Secondly, since each component is self-contained, it’s much easier to test and debug them individually. Finally, because all of the components are defined in one place, it’s simpler to maintain consistency across the entire application.

5. Prefer using pre-defined composables over writing raw views

The main reason for preferring pre-defined composables is that they are designed to be more efficient and easier to use than writing raw views. Pre-defined composables provide a set of APIs that allow developers to quickly create complex UI elements without having to write the code from scratch. This makes it much faster and simpler to build an app, as well as making it easier to maintain and update in the future. Additionally, pre-defined composables often come with built-in features such as accessibility support, which can save time and effort when developing an app.

When using pre-defined composables, developers should take advantage of the available APIs to customize their components. For example, many composables have parameters that can be used to adjust the size, color, or other properties of the component. By taking advantage of these parameters, developers can easily customize their components to fit their needs. Additionally, some composables also offer additional features such as animations or transitions, which can add extra visual appeal to an app.

6. Make sure all views are properly sized using Layout modifiers like width, height and padding

Using Layout modifiers like width, height and padding is important for ensuring that views are properly sized. This helps to ensure that the UI looks consistent across different devices with different screen sizes and resolutions. For example, if a view has an explicit size set using a Layout modifier, it will be displayed at the same size regardless of the device’s resolution or screen size. Without these modifiers, the view may appear too large on some devices and too small on others.

Layout modifiers also help to make sure that all views fit within their parent containers. If a view does not have its size specified, then it can take up more space than intended, which could cause other views in the layout to become misaligned or overlap each other. By setting explicit sizes for views, you can avoid this issue and ensure that everything fits together nicely.

Additionally, Layout modifiers allow developers to control how much spacing there is between views. Padding is used to add extra space around a view, while margins are used to add extra space outside of a view. This allows developers to create layouts that look aesthetically pleasing and organized. It also makes it easier to read and understand the code since the spacing between elements is clearly defined.

7. Leverage animations when appropriate to provide a more natural user experience

Animations are a great way to provide visual feedback and context for user interactions. Animations can be used to indicate that an action has been completed, or to show the progress of a task. They also help create a more immersive experience by providing subtle cues about what is happening in the app. For example, when a user taps on a button, an animation could be used to indicate that the action was successful.

Using animations with Android Jetpack Compose is easy thanks to its declarative UI framework. The AnimatedVisibility composable allows developers to animate the visibility of components, while the Transition composable provides a simple API for animating changes between two states. Additionally, there are several other APIs available for creating custom animations.

When using animations with Android Jetpack Compose, it’s important to keep performance in mind. Animations should be kept as lightweight as possible, and they should not interfere with the overall performance of the app. Developers should also consider how long each animation should last, as too many short animations can become distracting. Finally, animations should be tested across different devices to ensure that they look and feel consistent.

8. Prefer using Ambients to share data between multiple composables

Ambients are a type of composable that allow data to be shared between multiple composables in the same scope. This is done by wrapping the data in an ambient and then passing it down through the hierarchy as needed. Ambients can also be used to store global state, such as application-level settings or user preferences.

Using Ambients for sharing data has several advantages over other methods. Firstly, it allows data to be passed down without having to explicitly pass it from one composable to another. This makes code more concise and easier to read. Secondly, since the data is stored in an ambient, it can easily be accessed from any composable within the same scope. Finally, using ambients ensures that all components have access to the same version of the data, which helps prevent bugs caused by inconsistent data states.

When using Ambients, there are some important considerations to keep in mind. Firstly, it’s important to ensure that the data being stored in the ambient is immutable, as this will help prevent unexpected side effects. Secondly, it’s important to make sure that the ambient is only updated when necessary, as updating the ambient too often can lead to performance issues. Finally, it’s important to use unique keys for each ambient, as this will help avoid conflicts with other ambients.

9. Take advantage of the compose compiler optimizations to improve performance

Compose compiler optimizations are a set of features that allow developers to optimize their code for better performance. These optimizations can be used to reduce the amount of time it takes to compile and execute code, as well as improve the overall performance of an application.

The first optimization is inlining. Inlining allows the Compose compiler to replace calls to functions with the actual code from those functions. This reduces the number of function calls, which improves performance by reducing the overhead associated with making multiple function calls. Additionally, inlining also helps reduce the size of the compiled code, which can help reduce memory usage.

The second optimization is dead-code elimination. Dead-code elimination removes any code that isn’t being used or referenced in the application. This helps reduce the size of the compiled code, which can lead to improved performance due to reduced memory usage. It also helps reduce the amount of time it takes to compile the code, since the compiler doesn’t have to process unnecessary code.

The third optimization is constant folding. Constant folding replaces expressions that contain constants with the result of the expression. For example, if an expression contains two constants (e.g., 2 + 3), the compiler will replace the expression with the result (5). This helps reduce the amount of time it takes to evaluate the expression, which can lead to improved performance.

10. Test changes quickly by using the preview feature on Android Studio

The preview feature on Android Studio allows developers to quickly see the changes they make in their code. This is especially useful when using Android Jetpack Compose, as it provides a live preview of the UI components and how they will look with different configurations. The preview also updates automatically whenever any changes are made to the code, so developers can immediately see the effects of their modifications without having to manually rebuild the project or run the app.

Using the preview feature also helps developers identify potential issues early on in the development process. For example, if a developer adds a new component to the layout but forgets to add the necessary styling, they can easily spot this mistake by looking at the preview. This saves time and effort since the issue can be fixed before the app is even built.

Furthermore, the preview feature makes it easier for developers to experiment with different design options. Instead of writing multiple versions of the same code, developers can simply adjust the parameters of the existing components and instantly see the results. This allows them to find the best solution faster and more efficiently.