<!-- App colors -->
    <color name="lollipop_theme_default_primary">#3F51B5</color>
    <color name="lollipop_theme_default_primary_dark">#303F9F</color>
    <color name="lollipop_theme_default_accent">#C5CAE9</color>
    <color name="fab_color">#FF4081</color>


    <!-- Main theme colors -->
    <style name="MainLollipopTheme" parent="android:Theme.Material.Light">
        <item name="android:colorPrimary">@color/lollipop_theme_default_primary</item>
        <item name="android:colorPrimaryDark">@color/lollipop_theme_default_primary</item>
        <item name="android:statusBarColor">@color/lollipop_theme_default_primary_dark</item>
        <item name="android:colorAccent">@color/lollipop_theme_default_accent</item>
        <item name="android:colorControlHighlight">@color/lollipop_theme_default_accent</item>
        <item name="android:navigationBarColor">@color/lollipop_theme_default_primary</item>

        <!-- Main theme action bar-->
        <item name="android:actionBarStyle">@style/MainActionBar</item>
        <item name="android:actionBarTheme">@style/MainActionBarThemeOverlay</item>


        <!-- lag indicating whether this window requests that content changes be performed
             as scene changes with transitions -->
        <item name="android:windowContentTransitions">true</item>

        <!-- Flag indicating whether this Window's transition should overlap with
             the exiting transition of the calling Activity. -->
        <item name="android:windowAllowEnterTransitionOverlap">true</item>

        <!--Flag indicating whether this Window's transition should overlap with
             the exiting transition of the called Activity when the called Activity
             finishes. -->
        <item name="android:windowAllowExitTransitionOverlap">true</item>

        <!-- Flag indicating whether this window's Action Bar should overlay -->
        <item name="android:windowActionBarOverlay">false</item>

        <!-- Flag indicating whether this window's Action Bar content should overlay -->
        <item name="android:windowContentOverlay">@null</item>
    </style>

...
    <!-- fab button -->
    <ImageButton
        android:id="@+id/fab"
        android:layout_alignParentRight="true"
        android:layout_alignParentBottom="true"
        android:layout_width="@dimen/fab_size"
        android:layout_height="@dimen/fab_size"
        android:layout_gravity="bottom|right"
        android:layout_marginRight="16dp"
        android:layout_marginBottom="16dp"
        android:background="@drawable/fab_ripple"
        android:elevation="@dimen/button_elevation"
        android:onClick="onFabClicked"
        android:src="@drawable/ic_action_add"/>
...

        // Configure the FAB button
        int size = getResources().getDimensionPixelSize(R.dimen.fab_size);
        Outline outline = new Outline();
        outline.setOval(0, 0, size, size);
        findViewById(R.id.fab).setOutline(outline);

    <style name="MainLollipopTheme" parent="android:Theme.Material.Light">
        ...
        <!-- lag indicating whether this window requests that content changes be performed
       as scene changes with transitions -->
        <item name="android:windowContentTransitions">true</item>

        <!-- Flag indicating whether this Window's transition should overlap with
             the exiting transition of the calling Activity. -->
        <item name="android:windowAllowEnterTransitionOverlap">true</item>

        <!--Flag indicating whether this Window's transition should overlap with
             the exiting transition of the called Activity when the called Activity
             finishes. -->
        <item name="android:windowAllowExitTransitionOverlap">true</item>

        <!-- Flag indicating whether this window's Action Bar should overlay -->
        <item name="android:windowActionBarOverlay">false</item>

        <!-- Flag indicating whether this window's Action Bar content should overlay -->
        <item name="android:windowContentOverlay">@null</item>
        ...
    </style>
    

        // Setup the transition to the detail activity
        ActivityOptions options =  ActivityOptions.makeSceneTransitionAnimation(MainActivity.this, view, "photo" + i);
        startActivity(detailIntent, options.toBundle());