Explore foundational concepts of modern UI development with this Jetpack Compose basics quiz, designed to assess your understanding of composables, UI functions, state management, and layouts. Strengthen your grasp on essential components and best practices for building responsive and efficient user interfaces.
Which annotation is used to mark a function as a composable in Jetpack Compose?
Explanation: The @Composable annotation is required to define a composable function, which can be used to build UI elements declaratively. @ComposableFun, @UI, and @Layout are incorrect because they are not valid or relevant annotations in this context. Only @Composable signals the compiler that the function can participate in composition.
Which composable is typically used to display a simple line of text to the user?
Explanation: Text is the composable used to show a simple readable string on the screen in the Compose framework. Label, StringView, and Paragraph are not standard composables for displaying text, and using them would result in an error or unexpected behavior.
What is commonly used to manage and preserve UI state in Jetpack Compose?
Explanation: The remember function helps store state information across recompositions within a composable. Options like keepState, holdValue, and storeData are not valid functions and would not provide state management in this context.
Which composable arranges its children in a horizontal sequence?
Explanation: Row lays out its children in a horizontal line, making it ideal for horizontal alignment. Column arranges widgets vertically, Stack does not exist as a layout in Compose, and Box overlays items rather than arranging them horizontally.
In Jetpack Compose, what is a Modifier mainly used for?
Explanation: Modifiers allow you to adjust composables' appearance, layout, and behavior, such as padding, size, and background. Adding animations to lists, constructing navigation flows, or handling authentication is not the primary use of Modifiers.
Which parameter should be provided to handle a button's click event?
Explanation: The onClick lambda parameter lets you specify what happens when the button is clicked. onPress, onTap, and onTouch are incorrect because they are not valid parameters for Compose's Button composable.
What annotation should be used to preview a composable design during development?
Explanation: @Preview enables you to visualize a composable's appearance without launching the full application. @ShowUI, @Render, and @Visible are not recognized annotations for previewing composables.
If you want several UI elements stacked from top to bottom, which layout composable should you use?
Explanation: Column arranges its child composables in a vertical sequence from top to bottom. Row arranges items horizontally, Grid is not a standard layout in Compose basics, and Sequence is not a layout component.
What does recomposition mean in the context of Jetpack Compose?
Explanation: Recomposition refers to updating or re-executing specific UI parts when their data changes, ensuring the UI stays current. Updating project files, compiling code, or running background services are separate processes not directly tied to recomposition.
Which composable should you use to accept single-line text input from the user?
Explanation: TextField is the standard composable for collecting single-line or multi-line user text input. TextEntry and InputField are not standard Compose elements, and EditText is a term from older frameworks, not Jetpack Compose.