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class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        NetworkConnectLifecycle(this, lifecycle).run {
            networkChange = { handleNetworkChange(it) }
        }
    }

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fun Context.isOnline(): Boolean {
    val connectManager = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
    val activeNetwork = connectManager.activeNetwork ?: return false
    val activeNetworkCapabilities =
        connectManager.getNetworkCapabilities(activeNetwork) ?: return false
    return when {
        activeNetworkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI) -> true
        activeNetworkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR) -> true
        activeNetworkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET) -> true
        activeNetworkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_BLUETOOTH) -> true

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class NetworkConnectLifecycle(private val context: Context, private val lifecycle: Lifecycle) :
    LifecycleObserver,
    ConnectivityManager.NetworkCallback() {

    private val mConnectActivityManager: ConnectivityManager =
        context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager

    var networkChange: ((Boolean) -> Unit)? = null

    init {

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<resources>
    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.DayNight.DarkActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
    </style>

</resources>

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<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="colorPrimary">#463B5C</color>
    <color name="colorPrimaryDark">#463B5C</color>
    <color name="colorAccent">#463B5C</color>

    //Define color for text primary and divider (change color in color value-night)
    <color name="textColorPrimary">#111111</color>
    <color name="colorDivider">#E4E4E4</color>

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<?xml version="1.0" encoding="utf-8"?>
<resources>

    <color name="textColorPrimary">#ffffff</color>
    <color name="colorDivider">#101010</color>

</resources>

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/**
 * Created by nambv on 8/20/2020
 */
object PreferenceUtils {

    private const val PREFERENCE_NAME = "com.android.dark_theme_preferences"

    const val PREFERENCE_KEY_THEME = "key_theme"
    const val THEME_LIGHT = 0
    const val THEME_DARK = 1

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/**
 * Created by nambv on 10/5/2020
 */
class ThemeApplication : Application() {

    override fun onCreate() {
        super.onCreate()
        setupTheme()
    }

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class PreferenceObserverLifecycle(private val context: Context, private val lifecycle: Lifecycle) :
    LifecycleObserver, SharedPreferences.OnSharedPreferenceChangeListener {

    private val mPreference = PreferenceUtils.getAppPrefs(context)
    var themeConfigChange: (() -> Unit)? = null

    init {
        lifecycle.addObserver(this)
    }

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/**
 * Created by nambv on 10/5/2020
 */
abstract class BaseThemeActivity : AppCompatActivity() {

    @get:LayoutRes
    abstract val layoutId: Int

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