Android Programming: The Big Nerd Ranch Guide, 5th Edition

Querying the Database

Now that CrimeRepository is set up to pull data from a populated database, update CrimeListViewModel to access the database when loading crimes instead of using the dummy data.

Listing 12.23  Accessing your database (CrimeListViewModel.kt)

class CrimeListViewModel : ViewModel() {
  private val crimeRepository = CrimeRepository.get()

  val crimes = mutableListOf<Crime>()
  ...
  suspend fun loadCrimes(): List<Crime> {
      val result = mutableListOf<Crime>()
      delay(5000)
      for (i in 0 until 100) {
          val crime = Crime(
              id = UUID.randomUUID(),
              title = "Crime #$i",
              date = Date(),
              isSolved = i % 2 == 0
          )

          result += crime
      }
      return result
      return crimeRepository.getCrimes()
  }
}

Run the app and see the prepopulated crimes display ...