MainActivity.kt

MainActivity.kt

package de.comp.proj.androidApp

import android.os.Bundle
import android.view.MenuItem
import androidx.appcompat.app.ActionBarDrawerToggle
import androidx.appcompat.widget.Toolbar
import androidx.core.view.GravityCompat
import androidx.databinding.DataBindingUtil
import androidx.drawerlayout.widget.DrawerLayout
import androidx.lifecycle.Observer
import androidx.lifecycle.ViewModelProvider
import androidx.navigation.fragment.NavHostFragment
import androidx.navigation.ui.AppBarConfiguration
import androidx.navigation.ui.NavigationUI
import androidx.navigation.ui.navigateUp
import com.google.android.material.navigation.NavigationView
import de.comp.proj.androidApp.databinding.ActivityMainBinding
import de.comp.proj.androidApp.databinding.NavHeaderBinding
import de.comp.proj.androidApp.fragments.login.LoginFragmentDirections
import de.comp.proj.androidApp.fragments.login.LoginViewModel
import de.comp.proj.shared.models.LoginModel
import dev.icerock.moko.mvvm.MvvmEventsActivity
import dev.icerock.moko.mvvm.createViewModelFactory
import dev.icerock.moko.mvvm.dispatcher.eventsDispatcherOnMain
import dev.icerock.moko.resources.desc.StringDesc
import kotlinx.coroutines.MainScope
import kotlinx.coroutines.cancel

class MainActivity :
    MvvmEventsActivity<ActivityMainBinding, LoginModel, LoginModel.EventsListener>(),
    NavigationView.OnNavigationItemSelectedListener {
    private val mainScope = MainScope()

    override val layoutId: Int = R.layout.activity_main
    override val viewModelVariableId: Int = BR.viewModel
    override val viewModelClass: Class<LoginModel> =
        LoginModel::class.java

    val drawerLayout by lazy { findViewById<DrawerLayout>(R.id.drawerLayout) }
    val navController by lazy {
        (supportFragmentManager.findFragmentById(R.id.navHostFragment) as NavHostFragment).navController
    }
    val navigationView by lazy { findViewById<NavigationView>(R.id.navView) }

    private var loginModel: LoginModel? = null
    private lateinit var headerBinding: NavHeaderBinding


    private val appBarConfiguration by lazy {
        AppBarConfiguration(
            setOf(
                R.id.loginFragment,
                R.id.deviceListFragment,
                R.id.favouriteListFragment,
                R.id.imprintFragment
            ), drawerLayout
        )
    }

    override fun viewModelFactory(): ViewModelProvider.Factory {
        return createViewModelFactory {
            LoginModel(
                eventsDispatcher = eventsDispatcherOnMain()
            )
        }
    }

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

        setupDataBinding()
        setupNavigation()
        setupViewModel()
        hideLoggedNavItems()

        loginModel!!.logged.addObserver { logged ->
            logged.let {
                if (!logged) {
                    navController.popBackStack(R.id.loginFragment, false)
                }

                //if user logged in show relevant menu items
                val menu = navigationView.menu
                menu.findItem(R.id.loginFragment).isVisible = !logged
                menu.findItem(R.id.logout).isVisible = logged
                menu.findItem(R.id.accountFragment).isVisible = logged

                //invalidate header
                updateNavHeader()
            }
        }

    }

    private fun setupDataBinding() {

        headerBinding = DataBindingUtil.inflate(
            layoutInflater, R.layout.nav_header, binding.navView, false
        )

        binding.navView.addHeaderView(headerBinding.root)
    }

    private fun setupNavigation() {
        val toolbar = findViewById<Toolbar>(R.id.toolbar)
        setSupportActionBar(toolbar)

        val toggle = ActionBarDrawerToggle(
            this,
            drawerLayout,
            toolbar,
            R.string.navigation_drawer_open,
            R.string.navigation_drawer_close
        )
        drawerLayout.addDrawerListener(toggle)
        toggle.syncState()

        // Show and Manage the Drawer and Back Icon
        NavigationUI.setupActionBarWithNavController(this, navController, drawerLayout)

        NavigationUI.setupWithNavController(toolbar, navController, drawerLayout)
        NavigationUI.setupWithNavController(navigationView, navController)

        navController.addOnDestinationChangedListener { _, destination, _ ->
            if (destination.id == R.id.loginFragment) {
                loginModel?.onLogout()
            }
        }

        navigationView.setNavigationItemSelectedListener(this)
        navigationView.bringToFront()

        drawerLayout.isEnabled = true
    }

    //refresh navigation header after login or logout
    private fun updateNavHeader() {
        headerBinding.invalidateAll()
    }


    private fun setupViewModel() {
        try {
            val viewModelProvider = ViewModelProvider(
                navController.getViewModelStoreOwner(R.id.nav_graph),
                viewModelFactory()
            )
            loginModel = viewModelProvider.get(LoginModel::class.java)

            headerBinding.viewModel = loginModel
        } catch (e: IllegalArgumentException) {
            e.printStackTrace()
        }


    }

    private fun hideLoggedNavItems() {
        val menu = navigationView.menu
        menu.findItem(R.id.logout).isVisible = false
        menu.findItem(R.id.accountFragment).isVisible = false
        menu.findItem(R.id.loginFragment).isVisible = true

    }

    override fun onSupportNavigateUp(): Boolean {
        // Allows NavigationUI to support proper up navigation or the drawer layout
        // drawer menu, depending on the situation
        return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
    }

    override fun onOptionsItemSelected(item: MenuItem?): Boolean {
        return NavigationUI.onNavDestinationSelected(
            item!!,
            navController
        ) || super.onOptionsItemSelected(item)
    }


    fun onLoggedChange(logged: Boolean) {
        if (logged) {
            navController.popBackStack(R.id.loginFragment, false)
        }
        refreshMenuItems(logged)

    }

    fun refreshMenuItems(logged: Boolean) {
        //if user logged in show relevant menu items
        val menu = navigationView.menu
        menu.findItem(R.id.loginFragment).isVisible = !logged
        menu.findItem(R.id.logout).isVisible = logged
        menu.findItem(R.id.accountFragment).isVisible = logged

        //invalidate header
        updateNavHeader()
    }

    override fun onNavigationItemSelected(item: MenuItem): Boolean {
        when (item.itemId) {
            R.id.logout -> {
                loginModel?.onLogout()
            }
        }
        drawerLayout.closeDrawer(GravityCompat.START)
        return true
    }

    override fun onDestroy() {
        super.onDestroy()
        mainScope.cancel()
    }

}