Initial Movies UI

Create data

Now we create some fake data to display Movies in the app. After we talk about databases, we'll convert the data into something real (and add Actors and Ratings).

Create a Movie class. For now we just hold a title and description, but we'll add more when we create our database.

show in full file app/src/main/java/com/androidbyexample/compose/movies/Movie.kt

package com.androidbyexample.compose.movieui1

data class Movie(
    val title: String,
    val description: String,
)

Next, we create a MovieViewModel to hold a list of movies. View models prepare and provide data for our user interface to consume. Here we hardcode the data, but we'll change that in the database module.

show in full file app/src/main/java/com/androidbyexample/compose/movies/MovieViewModel.kt

// ...
import androidx.lifecycle.ViewModel

class MovieViewModel: ViewModel() {
    val movies: List<Movie> = listOf(
        Movie("The Transporter", "Jason Statham kicks a guy in the face"),
        Movie("Transporter 2", "Jason Statham kicks a bunch of guys in the face"),
        Movie("Hobbs and Shaw", "Cars, Explosions and Stuff"),
        Movie("Jumanji - Welcome to the Jungle", "The Rock smolders"),
    )
}

Finally, we connect the view model to the MainActivity. Using the viewModels function creates a property delegate that will create an instance of the specified view model (if it doesn't exist), or fetch an existing one for the activity. This allows us to keep data across configuration changes, when the activity is destroyed and recreated.

When adding the viewModels function, it'll show in red. Place your cursor on the word viewModels and press Alt+Enter to see your options. It'll show you an option to import the viewModels extension function. Selecting it will add an import at the top of the file and the error will go away.

show in full file app/src/main/java/com/androidbyexample/compose/movies/MainActivity.kt

// ...

class MainActivity : ComponentActivity() {
    private val viewModel by viewModels<MovieViewModel>()

    override fun onCreate(savedInstanceState: Bundle?) {
        // ...
}
// ...

---

All code changes

CHANGED: app/src/main/java/com/androidbyexample/compose/movies/MainActivity.kt

package com.androidbyexample.compose.movies

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.activity.enableEdgeToEdge
import androidx.activity.viewModels
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.padding
import androidx.compose.material3.Scaffold
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.tooling.preview.Preview
import com.androidbyexample.compose.movies.ui.theme.MoviesTheme
import com.androidbyexample.compose.movieui1.MovieViewModel

class MainActivity : ComponentActivity() {
    private val viewModel by viewModels<MovieViewModel>()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
        setContent {
            MoviesTheme {
                Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
                    Greeting(
                        name = "Android",
                        modifier = Modifier.padding(innerPadding)
                    )
                }
            }
        }
    }
}

@Composable
fun Greeting(name: String, modifier: Modifier = Modifier) {
    Text(
        text = "Hello $name!",
        modifier = modifier
    )
}

@Preview(showBackground = true)
@Composable
fun GreetingPreview() {
    MoviesTheme {
        Greeting("Android")
    }
}

ADDED: app/src/main/java/com/androidbyexample/compose/movies/Movie.kt

package com.androidbyexample.compose.movieui1

data class Movie(
    val title: String,
    val description: String,
)

ADDED: app/src/main/java/com/androidbyexample/compose/movies/MovieViewModel.kt

package com.androidbyexample.compose.movieui1

import androidx.lifecycle.ViewModel

class MovieViewModel: ViewModel() {
    val movies: List<Movie> = listOf(
        Movie("The Transporter", "Jason Statham kicks a guy in the face"),
        Movie("Transporter 2", "Jason Statham kicks a bunch of guys in the face"),
        Movie("Hobbs and Shaw", "Cars, Explosions and Stuff"),
        Movie("Jumanji - Welcome to the Jungle", "The Rock smolders"),
    )
}