Shared element transition of cover

app/src/main/java/de/danoeh/antennapod/activity/MediaplayerActivity.java

@@ -11,6 +11,7 @@ import android.net.Uri;
 import android.os.Build;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
+import android.support.v4.app.ActivityOptionsCompat;
 import android.support.v7.app.AlertDialog;
 import android.util.Log;
 import android.view.Menu;
@@ -368,7 +369,16 @@ public abstract class MediaplayerActivity extends CastEnabledActivity implements
                     MainActivity.class);
             intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP
                     | Intent.FLAG_ACTIVITY_NEW_TASK);
-            startActivity(intent);
+
+            View cover = findViewById(R.id.imgvCover);
+            if (cover != null && Build.VERSION.SDK_INT >= 16) {
+                ActivityOptionsCompat options = ActivityOptionsCompat.
+                        makeSceneTransitionAnimation(MediaplayerActivity.this,
+                        cover, "coverTransition");
+                startActivity(intent, options.toBundle());
+            } else {
+                startActivity(intent);
+            }
             return true;
         } else {
             if (media != null) {

app/src/main/java/de/danoeh/antennapod/activity/MediaplayerInfoActivity.java

@@ -6,6 +6,7 @@ import android.content.Intent;
 import android.content.SharedPreferences;
 import android.content.res.Configuration;
 import android.os.Build;
+import android.os.Bundle;
 import android.support.annotation.Nullable;
 import android.support.design.widget.AppBarLayout;
 import android.support.design.widget.Snackbar;
@@ -112,6 +113,12 @@ public abstract class MediaplayerInfoActivity extends MediaplayerActivity implem
         EventBus.getDefault().unregister(this);
     }
 
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        supportPostponeEnterTransition();
+    }
+
     @Override
     protected void onStop() {
         super.onStop();
@@ -277,6 +284,8 @@ public abstract class MediaplayerInfoActivity extends MediaplayerActivity implem
         pageIndicator.setViewPager(pager);
         loadLastFragment();
         pager.onSaveInstanceState();
+
+        navList.post(this::supportStartPostponedEnterTransition);
     }
 
     @Override

app/src/main/java/de/danoeh/antennapod/fragment/ExternalPlayerFragment.java

@@ -1,6 +1,9 @@
 package de.danoeh.antennapod.fragment;
 
+import android.content.Intent;
+import android.os.Build;
 import android.os.Bundle;
+import android.support.v4.app.ActivityOptionsCompat;
 import android.support.v4.app.Fragment;
 import android.util.Log;
 import android.view.LayoutInflater;
@@ -56,8 +59,15 @@ public class ExternalPlayerFragment extends Fragment {
             Log.d(TAG, "layoutInfo was clicked");
 
             if (controller != null && controller.getMedia() != null) {
-                startActivity(PlaybackService.getPlayerActivityIntent(
-                        getActivity(), controller.getMedia()));
+                Intent intent = PlaybackService.getPlayerActivityIntent(getActivity(), controller.getMedia());
+
+                if (Build.VERSION.SDK_INT >= 16) {
+                    ActivityOptionsCompat options = ActivityOptionsCompat.
+                            makeSceneTransitionAnimation(getActivity(), imgvCover, "coverTransition");
+                    startActivity(intent, options.toBundle());
+                } else {
+                    startActivity(intent);
+                }
             }
         });
         return root;

app/src/main/res/layout/cover_fragment.xml

@@ -16,6 +16,7 @@
         android:scaleType="fitCenter"
         app:layout_aspectRatio="100%"
         app:layout_widthPercent="82%"
+        android:transitionName="coverTransition"
         tools:src="@android:drawable/sym_def_app_icon" />
 
     <LinearLayout

app/src/main/res/layout/external_player_fragment.xml

@@ -22,6 +22,7 @@
             android:scaleType="centerCrop"
             tools:src="@drawable/ic_drag_vertical_white_48dp"
             tools:background="@android:color/holo_green_dark"
+            android:transitionName="coverTransition"
             android:layout_alignParentTop="true"
             android:layout_alignParentLeft="true"
             android:layout_alignParentStart="true"/>

core/src/main/res/values-v21/styles.xml

@@ -1,5 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
+    <style name="Theme.AntennaPod.Light" parent="Theme.Base.AntennaPod.Light">
+        <item name="android:windowContentTransitions">true</item>
+    </style>
+    <style name="Theme.AntennaPod.Dark" parent="Theme.Base.AntennaPod.Dark">
+        <item name="android:windowContentTransitions">true</item>
+    </style>
 
     <style name="Widget.AntennaPod.Button" parent="Widget.AppCompat.Button">
         <item name="textAllCaps">true</item>