6. Lógica da Aplicação

6.4. Classe MainActivity

Configure a MainActivity para servir apenas como uma inicialização da aplicação.

package br.edu.ifsc.fulano.weatherapp

import android.os.Bundle
import com.google.android.material.snackbar.Snackbar
import androidx.appcompat.app.AppCompatActivity
import androidx.navigation.findNavController
import androidx.navigation.ui.AppBarConfiguration
import androidx.navigation.ui.navigateUp
import androidx.navigation.ui.setupActionBarWithNavController
import android.view.Menu
import android.view.MenuItem
import br.edu.ifsc.fulano.weatherapp.databinding.ActivityMainBinding

class MainActivity : AppCompatActivity() {

private lateinit var appBarConfiguration: AppBarConfiguration
private lateinit var binding: ActivityMainBinding

override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)

binding = ActivityMainBinding.inflate(layoutInflater)
setContentView(binding.root)

setSupportActionBar(binding.toolbar)

val navController = findNavController(R.id.nav_host_fragment_content_main)
appBarConfiguration = AppBarConfiguration(navController.graph)
setupActionBarWithNavController(navController, appBarConfiguration)
}

override fun onSupportNavigateUp(): Boolean {
val navController = findNavController(R.id.nav_host_fragment_content_main)
return navController.navigateUp(appBarConfiguration)
|| super.onSupportNavigateUp()
}
}