Toggling visibility AppBarLayout views causes spacing issues for loaded Fragments

Question

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I encountered a strange problem with the new Android Design Support Librar (http://android-developers.blogspot.com.ar/2015/05/android-design-support-library.html). If I place additional content (like a LinearLayout) in an AppBarLayout along with the ToolBar and toggle the visibility of that content then switching fragments will have show a dead space at the top of the fragment content.

It appears that AppBarLayout isn't resizing the parent CoordinatorLayout correctly when visibility of the content is toggled. I have my CoordinatorLayout wrapped in the DrawerLayout. I want to toggle the visibility of the extra LinearLayout in the AppBarLayout depending on the which fragment shown.

Here is my main.xml file for the MainActivity:

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

<android.support.design.widget.CoordinatorLayout
            android:layout_height="match_parent"
            android:layout_width="match_parent">

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

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

                <TextView
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:gravity="start"
                        android:text="Hello"/>
            </LinearLayout>

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

        <FrameLayout
           app:layout_behavior="@string/appbar_scrolling_view_behavior"
                android:id="@+id/content_frame"
                android:layout_width="match_parent"
                android:layout_height="match_parent"/>

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

  <android.support.design.widget.NavigationView
            android:id="@+id/navigation"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_gravity="start"
            app:menu="@menu/drawer"/>

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

Answer 1

I had a similar problem using the support design widget. I had a CoordinatorLayout inside a DrawerLayout and an AppBarLayout inside the CoordinatorLayout. I had two toolbars inside the AppBarLayout. My aim was to display a toolbar with a ViewPager displaying a recyclerview content. I wanted to swop between the toolbars when selecting items. In other words, I made one toolbar GONE while the other was visible and vise versa. Scrolling the content up would push the toolbar up off the top of the screen. Everything worked perfectly except that changing orientation would show a space for the toolbar that should be gone. I tried every hack I could think of to get rid of it but did not succeed. I then came across this post and realized that it was a bug in the support library. I then tried putting a FrameLayout in the AppBarLayout and then put the two toolbars inside the FrameLayout and NO MORE SPACE! everything now works as I intend it to work. GONE toolbars are GONE and only the visible toolbar shows, even when changing the orientation.

Hope this helps someone.