McGuile McGuile - 1 month ago 8
Android Question

CoordinatorLayout Toolbar invisible on enter until full height

Included in my activity_main.xml's

DrawerLayout
is a
CoordinatorLayout
called content_layout.xml. Within this
CoordinatorLayout
is my
AppBarLayout
containing a
Toolbar
, then a
LinearLayout
for a fragment's content.

When a fragment containing a
RecyclerView
is scrolled up, the toolbar exits successfully. The problem lies when scrolling down to bring the toolbar back. The toolbar does not appear until the full height of the toolbar has been scrolled and as such leaves an unsightly white box in its place as shown.

toolbar

content_layout.xml

<android.support.design.widget.CoordinatorLayout
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/container_frame"
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"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />

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

<!-- The main content view for fragments-->
<LinearLayout
android:id="@+id/content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
app:layout_behavior="@string/appbar_scrolling_view_behavior"/>

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


The toolbar is initialized via
MainActivity
's
onCreate()
:

Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setHomeButtonEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);


I would appreciate any suggestions as to resolving this. Thank you.

Answer

I was having this same issue and the only thing I found that solved it was by having something else other than the toolbar inside the AppBarLayout. I placed an invisible view in my layout underneath the toolbar. Not the most ideal solution, but it worked.

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

     <View
        android:id="@+id/appbar_bottom"
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="@android:color/transparent"
        android:visibility="invisible"/>

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