android-appbarlayout.md

title: Android Design Library: AppBarLayout tags: android,android-appbarlayout

The AppBarLayout--working within a CoordinatorLayout--allows you to scroll the stuff in the app bar, namly the toolbar and tablayout most likely, when you scroll a inner container, like a RecyclerView.

The scrollabel view must have a app:layout_behavior="@string/appbar_scrolling_view_behavior" else it'll overlap the AppBarLayout.

It must also be within the CoordinatorLayout that holds the AppBarLayout.

The app:layout_scrollFlags= flags control how the views within will be scrolled.

<android.support.design.widget.CoordinatorLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    >
  <android.support.design.widget.AppBarLayout
      android:id="@+id/appbar"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      >
    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        app:layout_scrollFlags="scroll|enterAlways"
        />
    <android.support.design.widget.TabLayout
        android:id="@+id/tabLayout"
        style="@style/AppTheme.TabLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:layout_scrollFlags="scroll|enterAlways"
        app:tabGravity="fill"
        app:tabMode="scrollable"
        />
  </android.support.design.widget.AppBarLayout>
  <android.support.v7.widget.RecyclerView
      android:id="@+id/rec_view"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      app:layout_behavior="@string/appbar_scrolling_view_behavior"
      android:layout_below="@+id/appbar"
      />
</android.support.design.widget.CoordinatorLayout

If you leave out the scrollFlags from the TabLayout, you can scroll away the Toolbar but leave the TabLayout. Scream if you want to go faster.