Managing App Configuration

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        if (BuildConfig.DEBUG) {
            Log.d("MainActivity", "App is running in debug mode")
        }

        val versionName = BuildConfig.VERSION_NAME
        Log.d("MainActivity", "App Version: $versionName")
    }
}

android {
    buildTypes {
        getByName("debug") {
            isDebuggable = true
            applicationIdSuffix = ".debug"
        }

        getByName("release") {
            isMinifyEnabled = true
            proguardFiles getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro"
        }
    }

    flavorDimensions("version")
    productFlavors {
        create("free") {
            dimension = "version"
            applicationIdSuffix = ".free"
        }

        create("paid") {
            dimension = "version"
            applicationIdSuffix = ".paid"
        }
    }
}

class MyApplication : Application() {
    override fun onCreate() {
        super.onCreate()
        // Initialize global state here
        Log.d("MyApp", "Application created")
    }
}

<application
    android:name=".MyApplication"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name">
</application>

import android.app.Application
import android.util.Log

class MyApplication : Application() {
    override fun onCreate() {
        super.onCreate()
        Log.d("MyApp", "Application initialized")
        // Initialize third-party libraries here
        // e.g., Firebase, Crashlytics, etc.
    }
}

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.app">
    <application>
        <activity
            android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.app">
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <application>
        ...
    </application>
</manifest>

<activity
    android:name=".MainActivity"
    android:label="@string/app_name"
    android:theme="@style/Theme.AppCompat.Light"
    android:exported="true"
    android:launchMode="singleTop"
    android:screenOrientation="portrait">
</activity>

<resources>
    <style name="AppTheme" parent="Theme.AppCompat.Light">
        <item name="colorPrimary">&#64;color/primary_color</item>
        <item name="colorPrimaryDark">&#64;color/primary_dark</item>
        <item name="colorAccent">&#64;color/accent_color</item>
    </style>
</resources>

<application
    android:theme="&#64;style/AppTheme">
    ...
</application>

val metadata = packageManager.getApplicationInfo(
    packageName,
    PackageManager.GET_META_DATA
).metaData

val apiKey = metadata.getString("com.example.api_key")
val version = metadata.getString("version")

<activity
    android:name=".DeepLinkActivity"
    android:exported="true">
    <intent-filter>
        <action android:name="android.intent.action.VIEW" />
        <category android:name="android.intent.category.DEFAULT" />
        <category android:name="android.intent.category.BROWSABLE" />
        <data
            android:scheme="https"
            android:host="myapp.com"
            android:pathPrefix="/deep" />
    </intent-filter>
</activity>

class DeepLinkActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_deep_link)

        val uri = intent.data
        if (uri != null) {
            // Handle the deep link data
            val path = uri.path
            val param = uri.getQueryParameter("param")
        }
    }
}

class FeatureFlags {
    companion object {
        const val NEW_UI = "feature_new_ui"
        const val PUSH_NOTIFICATIONS = "feature_push_notifications"
        const val ANALYTICS = "feature_analytics"
    }
}

fun isFeatureEnabled(flag: String): Boolean {
    return when (flag) {
        FeatureFlags.NEW_UI -> false
        FeatureFlags.PUSH_NOTIFICATIONS -> true
        FeatureFlags.ANALYTICS -> true
        else -> false
    }
}