CoordinatorLayout with Toolbar and fragment

Question

I'm using the layout below, The CoordinatorLayout holds inside it AppBarLayout (With Toolbar and TabLayout inside it) and a placeholder RelativeLayout, so I could add and replace fragments on it.

I'm experiencing margin errors, the fragments I add on the RelativeLayout will always over expand beyond the bottom of the screen (in the amount similar to the size of the AppBarLayout height), I've tried setting it's height to wrap_content and match_parent, in both cases it goes overboard.

if I remove the app:layout_behavior="@string/appbar_scrolling_view_behavior" from the RelativeLayout the top of it will be under the AppBarLayout which is also not the desired outcome.

<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/drawer_layout"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:fitsSystemWindows="true">

    <android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
        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.support.design.widget.AppBarLayout
            android:id="@+id/appbar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

        <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/ThemeOverlay.AppCompat.Light"
                app:layout_scrollFlags="scroll|enterAlways" />

            <android.support.design.widget.TabLayout
                android:id="@+id/tabs"
                app:tabIndicatorHeight="4dp"
                app:tabIndicatorColor="#ffffff"
                app:tabMode="scrollable"
                android:visibility="gone"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />

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


        <RelativeLayout
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
            android:id="@+id/main_fragment_container"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>


       <android.support.design.widget.FloatingActionButton
            android:id="@+id/fab"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="end|bottom"
            android:layout_margin="20dp"
            android:src="@drawable/ic_done" />


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

<android.support.design.widget.NavigationView
    android:id="@+id/nav_view"
    android:layout_height="match_parent"
    android:layout_width="wrap_content"
    android:layout_gravity="start"
    android:fitsSystemWindows="true"
    app:headerLayout="@layout/nav_header"
    app:menu="@menu/drawer_view"/>

</android.support.v4.widget.DrawerLayout>

Answer 1

I have figured out the problem on showing fragment below toolbar when using the coordinator layout. The problem in my case is:

In this image it shows the Fragment is overlapped by Toolbar.

Now just put your AppBarLayout and FrameLayout inside LinearLayout like below,

<LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <android.support.design.widget.AppBarLayout
            android:id="@+id/mainappbar"
            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"/>

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

        <FrameLayout
            android:id="@+id/frame_container"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
    </LinearLayout>

Now your problem is solved. And it will be like this.

The final image.