fix(android): rework the splashscreen implementation (#377)

Co-authored-by: jeremydolle <j.dolle@thecodingmachine.com>

Author: JeremyDolle

template/android/app/src/main/AndroidManifest.xml

@@ -11,27 +11,17 @@
       android:theme="@style/AppTheme"
     >
       <activity
-        android:name=".SplashActivity"
-        android:theme="@style/SplashTheme"
-        android:label="@string/app_name"
-        android:exported="true"
-      >
+          android:name=".MainActivity"
+          android:label="@string/app_name"
+          android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|screenSize|smallestScreenSize|uiMode"
+          android:launchMode="singleTask"
+          android:theme="@style/SplashTheme"
+          android:windowSoftInputMode="adjustResize"
+          android:exported="true">
         <intent-filter>
           <action android:name="android.intent.action.MAIN" />
           <category android:name="android.intent.category.LAUNCHER" />
         </intent-filter>
       </activity>
-
-      <activity
-        android:name=".MainActivity"
-        android:label="@string/app_name"
-        android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|screenSize|smallestScreenSize|uiMode"
-        android:launchMode="singleTask"
-        android:windowSoftInputMode="adjustResize"
-        android:exported="true">
-        <intent-filter>
-          <action android:name="android.intent.action.MAIN" />
-        </intent-filter>
-      </activity>
     </application>
 </manifest>

template/android/app/src/main/java/com/boilerplate/MainActivity.java

@@ -4,6 +4,7 @@
 import com.facebook.react.ReactActivityDelegate;
 import com.facebook.react.defaults.DefaultNewArchitectureEntryPoint;
 import com.facebook.react.defaults.DefaultReactActivityDelegate;
+import android.os.Bundle;
 
 public class MainActivity extends ReactActivity {
 
@@ -29,4 +30,10 @@ protected ReactActivityDelegate createReactActivityDelegate() {
         // If you opted-in for the New Architecture, we enable the Fabric Renderer.
         DefaultNewArchitectureEntryPoint.getFabricEnabled());
   }
+
+  @Override
+  protected void onCreate(Bundle savedInstance) {
+    super.onCreate(savedInstance);
+    setTheme(R.style.AppTheme);
+  }
 }