Update splash screen to properly use the Androidx SplashScreen library (#4413)

The Androidx SplashScreen library is added as a dependency to the
project but isn't properly enabled in the current code. This pull
request configures the splash screen properly.

- Remove `SplashScreenActivity` which is not needed and use
`MainActivity` as main entry point to the application. `MainActivity`
inherits from `BaseActivity` which already detects if no account is
configured and redirects to `LoginActivity` if needed, just like
`SplashScreenActivity`.
- Initialize the SplashScreen library in `MainActivity.onCreate()`.
- Instead of letting the SplashScreen library set the final theme from
the `postSplashScreenTheme` attribute in SplashTheme, let `BaseActivity`
set it according to the user settings.
- When no account is available in `MainActivity.onCreate()`, keep the
splash screen shown until `LoginActivity` appears.
- Disable the slide-in animation when launching `LoginActivity` when no
account is available because the detection happens in `onCreate()` and
an Activity that finishes itself in `onCreate()` will not be drawn, so
the slide-in animation will not be visible either and only
`LoginActivity` will appear.
- Upgrade `core-splashscreen` to 1.2.0-alpha01 which contains a fix for
corrupted app theme on API 31+.

app/src/main/java/com/keylesspalace/tusky/BaseActivity.java

@@ -102,6 +102,8 @@ public abstract class BaseActivity extends AppCompatActivity {
         Log.d("activeTheme", theme);
         if (ThemeUtils.isBlack(getResources().getConfiguration(), theme)) {
             setTheme(R.style.TuskyBlackTheme);
+        } else {
+            setTheme(R.style.TuskyTheme);
         }
 
         /* set the taskdescription programmatically, the theme would turn it blue */
@@ -207,9 +209,9 @@ public abstract class BaseActivity extends AppCompatActivity {
     protected void redirectIfNotLoggedIn() {
         AccountEntity account = accountManager.getActiveAccount();
         if (account == null) {
-            Intent intent = new Intent(this, LoginActivity.class);
+            Intent intent = LoginActivity.getIntent(this, LoginActivity.MODE_DEFAULT);
             intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK);
-            ActivityExtensions.startActivityWithSlideInAnimation(this, intent);
+            startActivity(intent);
             finish();
         }
     }

app/src/main/java/com/keylesspalace/tusky/MainActivity.kt

@@ -46,6 +46,7 @@ import androidx.coordinatorlayout.widget.CoordinatorLayout
 import androidx.core.app.ActivityCompat
 import androidx.core.content.ContextCompat
 import androidx.core.content.pm.ShortcutManagerCompat
+import androidx.core.splashscreen.SplashScreen.Companion.installSplashScreen
 import androidx.core.view.MenuProvider
 import androidx.core.view.forEach
 import androidx.core.view.isVisible
@@ -203,10 +204,15 @@ class MainActivity : BottomSheetActivity(), ActionButtonActivity, MenuProvider {
 
     @SuppressLint("RestrictedApi")
     override fun onCreate(savedInstanceState: Bundle?) {
+        val splashScreen = installSplashScreen()
         super.onCreate(savedInstanceState)
 
         val activeAccount = accountManager.activeAccount
-            ?: return // will be redirected to LoginActivity by BaseActivity
+        if (activeAccount == null) {
+            splashScreen.setKeepOnScreenCondition { true }
+            // will be redirected to LoginActivity by BaseActivity
+            return
+        }
 
         if (explodeAnimationWasRequested()) {
             overrideActivityTransitionCompat(

app/src/main/java/com/keylesspalace/tusky/SplashActivity.kt

@@ -1,47 +0,0 @@
-/* Copyright 2018 Conny Duck
- *
- * This file is a part of Tusky.
- *
- * This program is free software; you can redistribute it and/or modify it under the terms of the
- * GNU General Public License as published by the Free Software Foundation; either version 3 of the
- * License, or (at your option) any later version.
- *
- * Tusky is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
- * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
- * Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with Tusky; if not,
- * see <http://www.gnu.org/licenses>. */
-
-package com.keylesspalace.tusky
-
-import android.annotation.SuppressLint
-import android.content.Intent
-import android.os.Bundle
-import androidx.appcompat.app.AppCompatActivity
-import com.keylesspalace.tusky.components.login.LoginActivity
-import com.keylesspalace.tusky.db.AccountManager
-import dagger.hilt.android.AndroidEntryPoint
-import javax.inject.Inject
-
-@SuppressLint("CustomSplashScreen")
-@AndroidEntryPoint
-class SplashActivity : AppCompatActivity() {
-
-    @Inject
-    lateinit var accountManager: AccountManager
-
-    override fun onCreate(savedInstanceState: Bundle?) {
-        super.onCreate(savedInstanceState)
-
-        /** Determine whether the user is currently logged in, and if so go ahead and load the
-         *  timeline. Otherwise, start the activity_login screen. */
-        val intent = if (accountManager.activeAccount != null) {
-            Intent(this, MainActivity::class.java)
-        } else {
-            LoginActivity.getIntent(this, LoginActivity.MODE_DEFAULT)
-        }
-        startActivity(intent)
-        finish()
-    }
-}