http://stackoverflow.com/questions/42274607/shared-element-transition-on-cardview-with-radius?noredirect=1#comment71706511_42274607

transition-layouts.xml

<!--- 
  list_item_animal.xml 
-->
    <android.support.v7.widget.CardView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:cardCornerRadius="25dp"
        android:padding="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_marginTop="100dp"
    >

        <RelativeLayout
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:onClick="@{(view) -> handler.onAnimalClick(view, animal)}"
        >

            <ImageView
                android:id="@+id/iv_image"
                android:layout_width="200dp"
                android:layout_height="150dp"
                android:contentDescription="a pic"
                android:scaleType="centerCrop"
                android:layout_centerHorizontal="true"
                android:src="@{animal.imageRes}"
            />

            <TextView
                android:id="@+id/tv_name"
                android:layout_width="200dp"
                android:layout_height="wrap_content"
                android:layout_below="@id/iv_image"
                android:layout_centerHorizontal="true"
                android:gravity="center"
                android:padding="12dp"
                android:background="@android:color/white"
                android:textAppearance="@style/TextAppearance.AppCompat.Title"
                android:text="@{animal.name}"
            />

        </RelativeLayout>
    </android.support.v7.widget.CardView>
    
<!--- 
  activity_detail.xml 
-->

  <RelativeLayout
      android:id="@+id/rl_container"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      >

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        >

      <ImageView
          android:id="@+id/iv_image_cover"
          android:layout_width="match_parent"
          android:layout_height="250dp"
          android:scaleType="centerCrop"
          android:src="@{animal.imageRes}"
          android:transitionName="animalImage"
          tools:src="@drawable/acat"
          />

      <android.support.v7.widget.Toolbar
          android:id="@+id/toolbar"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:alpha=".6"
          android:background="@android:color/black"
          android:fitsSystemWindows="true"
          android:minHeight="?attr/actionBarSize"
          android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
          android:transitionName="toolbar"
          app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
          />

    </FrameLayout>

    <android.support.v7.widget.RecyclerView
        android:id="@+id/rv_plants"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="150dp"
        />

    <android.support.v7.widget.RecyclerView
        android:id="@+id/rv_tribes"
        android:layout_width="match_parent"
        android:layout_height="200dp"
        android:layout_alignParentBottom="true"
        />

  </RelativeLayout>