Remove dark colour at the top of actionbar

Question

I have been having quite a problem figuring out how to get rid of the dark line at the top of the action bar. There is a picture in the link showing where the dark line is. I was wondering if there was a way to get rid of it. It seem like a very simple problem but I cannot find anything on the web on how to get rid of it.

Any help is appreciated

Here is my xml layout

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" android:layout_height="match_parent">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingTop="@dimen/appbar_padding_top"
        android:theme="@style/AppTheme.AppBarOverlay"
        android:layout_alignParentTop="true"
        style="@style/Base.Theme.AppCompat.Light">

        <android.support.design.widget.TabLayout
            android:id="@+id/tabs"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:fillViewport="false" />

    </android.support.design.widget.AppBarLayout>

</RelativeLayout>

Answer 1

Make sure the Activity containing the AppBarLayout has a theme that includes these attributes:

    <item name="windowActionBar">false</item>
    <item name="windowNoTitle">true</item>

Using an AppBarLayout is effectively creating your own App Bar (formerly known as an Action Bar), instead of using the built-in system one. But if your theme doesn't hide the system app bar, you will end up with two, which can cause the artifact you are seeing.

Also, I don't believe you need the android:paddingTop, app:elevation, or style attributes in your AppBarLayout. Here is code from my AppBarLayout with tabs at the top of my Activity, and it works perfectly for me:

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.design.widget.TabLayout
            android:id="@+id/tabs"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:tabIndicatorColor="@android:color/white"/>

    </android.support.design.widget.AppBarLayout>

However, you probably want to include a ToolBar in there to use as your action bar, like so:

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:layout_scrollFlags="scroll|enterAlways"
            app:popupTheme="@style/AppTheme.PopupOverlay">

        </android.support.v7.widget.Toolbar>

        <android.support.design.widget.TabLayout
            android:id="@+id/tabs"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:tabIndicatorColor="@android:color/white"/>

    </android.support.design.widget.AppBarLayout>

Then in your Activity's onCreate() method, make sure you set up the Toolbar as the ActionBar like so:

    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

Answer 2

Add this to your AppBar layout:

app:elevation="0dp"

Your fixed xml layout:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" android:layout_height="match_parent">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingTop="@dimen/appbar_padding_top"
        android:theme="@style/AppTheme.AppBarOverlay"
        android:layout_alignParentTop="true"
        app:elevation="0dp"
        style="@style/Base.Theme.AppCompat.Light">

        <android.support.design.widget.TabLayout
            android:id="@+id/tabs"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:fillViewport="false" />

    </android.support.design.widget.AppBarLayout>

</RelativeLayout>

Also, try this:

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto" android:id="@+id/main_content"
    android:layout_width="match_parent" android:layout_height="match_parent"
    android:fitsSystemWindows="true">

    <android.support.design.widget.AppBarLayout android:id="@+id/appbar"
        android:layout_width="match_parent" android:layout_height="wrap_content"
        android:paddingTop="@dimen/appbar_padding_top"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar android:id="@+id/toolbar"
            android:layout_width="match_parent" android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary" app:popupTheme="@style/AppTheme.PopupOverlay"
            app:layout_scrollFlags="scroll|enterAlways">

        </android.support.v7.widget.Toolbar>

        <android.support.design.widget.TabLayout android:id="@+id/tabs"
            android:layout_width="match_parent" android:layout_height="wrap_content" />

    </android.support.design.widget.AppBarLayout>

</android.support.design.widget.CoordinatorLayout>