Develop Reference

liftOnScroll not working with NestedScrollView

When I set app:liftOnScroll="true" to my AppBarLayout, and then launch the app, I don't see any shadow, and scrolling down or up doesn't work.
My Layout:
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto">
<!--.....................................................regular-->
<com.google.android.material.appbar.AppBarLayout
app:liftOnScroll="true"
android:fitsSystemWindows="true"
android:theme="#style/ThemeOverlay.Catalog.AppBarLayout"
android:id="#+id/toolbar_regular"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.google.android.material.appbar.MaterialToolbar
android:id="#+id/topAppBar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:title="Regular top app bar"
app:menu="#menu/menu_with_icons"
app:navigationIcon="#drawable/ic_drawer_white"
/>
</com.google.android.material.appbar.AppBarLayout>
<androidx.core.widget.NestedScrollView
android:id="#+id/nested_scroll_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#f5f5f5"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<include layout="#layout/top_appbar_filler_text_view" />
</androidx.core.widget.NestedScrollView>
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:layout_gravity="bottom|end"
android:id="#+id/fab_add"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="#dimen/spacing_middle"
android:layout_marginLeft="#dimen/spacing_smlarge"
android:layout_marginRight="#dimen/spacing_smlarge"
android:layout_marginTop="#dimen/spacing_middle"
android:clickable="true"
android:tint="#android:color/white"
app:backgroundTint="#android:color/black"
app:fabSize="normal"
app:tint="#color/white"
app:rippleColor="#android:color/white"
app:srcCompat="#drawable/ic_baseline_edit_24"
android:focusable="true"
android:contentDescription="#string/fab_description" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
Version:
implementation 'com.google.android.material:material:1.3.0-beta01'
Ref doc:
Applying scrolling behavior to the top app bar
https://material.io/components/app-bars-top/android#regular-top-app-bar
It should increases elevation and lets content scroll behind it.

It's hard to notice.
Try setting both App bar and Main background white and you will see the shadow.

Toolbar in the wrong location on BottomNavigationView

I'm building an app and when I load the view with the BottomNavigationView, I have odd issues all the time, sometimes, I have an extra space and other times, the toolbar is wrongly located, for example:
With bottom navigation:
Without bottom navigation:
This is my code for the 1st image:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:background="#android:color/white"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include
layout="#menu/toolbar_recipe" />
<FrameLayout
android:id="#+id/content_frame"
android:layout_height="0dp"
android:layout_weight="1"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:layout_width="match_parent" />
<android.support.design.widget.BottomNavigationView
android:id="#+id/bottom_navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
app:menu="#menu/bottom_nav_menu"
app:labelVisibilityMode="unlabeled"
app:itemBackground="#color/colorPrimary"
app:itemIconTint="#color/bottom_nav_color"
app:itemTextColor="#color/bottom_nav_color" />
</LinearLayout>
</RelativeLayout>
Toolbar:
<?xml version="1.0" encoding="UTF-8" ?>
<android.support.v7.widget.Toolbar
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/toolbar_recipe"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:theme="#style/ToolBarStyle"
android:minHeight="?android:attr/actionBarSize"
android:background="#color/colorPrimary"/>
And this is how it behaves with the CoordinatorLayout, after I set the paddingTop as ?attr/actionBarSize the FrameLayout moved some space, but it's still wrongly located.
With CoordinatorLayout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:background="#android:color/white"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
android:layout_above="#+id/bottom_navigation">
<include
layout="#menu/toolbar_recipe" />
<FrameLayout
android:id="#+id/content_frame"
android:paddingTop="?attr/actionBarSize"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</android.support.design.widget.CoordinatorLayout>
<android.support.design.widget.BottomNavigationView
android:id="#+id/bottom_navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
app:menu="#menu/bottom_nav_menu"
app:labelVisibilityMode="unlabeled"
app:itemBackground="#color/colorPrimary"
app:itemIconTint="#color/bottom_nav_color"
app:itemTextColor="#color/bottom_nav_color" />
</RelativeLayout>
Without that addition, it just stays behind. I'm working in Android 8+, but I don't think it's the issue and I'm out of ideas how to coordinate that situation. Has anyone experienced it?
Thanks for any comment, especially of why it's happening since I cannot understand it.

I found the answer based on this line:
android:fitsSystemWindows="true"
I needed to add it to the root element more or less like this:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:background="#android:color/white"
android:layout_width="match_parent"
android:fitsSystemWindows="true"
android:layout_height="match_parent">
And here is a description of the property:
System windows are the parts of the screen where the system is drawing
either non-interactive (in the case of the status bar) or interactive
(in the case of the navigation bar) content.
Most of the time, your app won’t need to draw under the status bar or
the navigation bar, but if you do: you need to make sure interactive
elements (like buttons) aren’t hidden underneath them. That’s what the
default behavior of the android:fitsSystemWindows="true" attribute
gives you: it sets the padding of the View to ensure the contents
don’t overlay the system windows.
I found it here:
Why would I want to fitsSystemWindows?

Umano SlidingUpPanel not working in CoordinatorLayout

I'm using Umano SlidingUpPanel to set a view like the following:
But no matter what I do, It can't be shown hidden. Instead, it's "peeking":
I need it to hide completely. This is my XML resource
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
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:layout_height="match_parent"
android:layout_width="match_parent"
xmlns:sothree="http://schemas.android.com/tools"
android:id="#+id/coordinator_layout"
tools:context="com.pocket.poktsales.activities.InventoryActivity">
<android.support.design.widget.AppBarLayout
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:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<ProgressBar
android:id="#+id/progressBar"
style="?android:attr/progressBarStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical|center_horizontal"
app:layout_anchorGravity="center_vertical|center_horizontal" />
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="#dimen/fab_margin"
android:src="#drawable/ic_box_add" />
<com.sothree.slidinguppanel.SlidingUpPanelLayout
android:layout_height="wrap_content"
android:layout_width="match_parent"
sothree:umanoDragView="#+id/sliding_up_panel"
android:gravity="bottom"
sothree:overlay="false"
sothree:umanoPanelHeight="0dp"
sothree:umanoParalaxOffset="100dp"
sothree:umanoShadowHeight="4dp">
<include
android:id="#+id/include"
layout="#layout/content_inventory" />
<include android:id="#+id/sliding_up_panel"
layout="#layout/content_product_detail"/>
</com.sothree.slidinguppanel.SlidingUpPanelLayout>
</android.support.design.widget.CoordinatorLayout>
I have tried:
use 0 dp for panel height, no results. Actually it'snot even affected by that attribute no matter what's the value.
Wrap it inside a frame Layout with no result.
Can anyone help me to hide it completely?

In my particular case, I added the panel height programatically:
panel.setPanelHeight(0);
And now it's working!

AppBarLayout scrolling content below Toolbar

I'd like to have a content area below my Toolbar. Its behavior should be to scroll while scrolling up and to enter immediately while scrolling down. Toolbar should stay on its place without any scrolling.
My layout is like that:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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/coordinator_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ui.MainActivity">
<android.support.design.widget.AppBarLayout
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:popupTheme="#style/AppTheme.PopupOverlay" />
<RelativeLayout
android:id="#+id/box_search"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="16dp"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
app:layout_scrollFlags="scroll|enterAlways">
<TextView
android:id="#+id/text_search_filter"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Line 1"
android:textColor="#FFF" />
<TextView
android:id="#+id/text_search_category"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/text_search_filter"
android:text="Line 2"
android:textColor="#FFF" />
<TextView
android:id="#+id/text_search_location"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/text_search_category"
android:text="Line 3"
android:textColor="#FFF" />
</RelativeLayout>
</android.support.design.widget.AppBarLayout>
<include layout="#layout/content_main" />
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="#dimen/fab_margin"
android:src="#drawable/ic_add_white_24dp" />
</android.support.design.widget.CoordinatorLayout>
If I put content area above Toolbar I am able to get the desired effect, but obviously it's in the wrong position.
If I put content area below Toolbar nothing scrolls...

If I put content area above Toolbar I am able to get the desired
effect, but obviously it's in the wrong position.
Of course it is in the wrong position since: http://www.google.com/design/spec/layout/structure.html#structure-app-bar
The app bar, formerly known as the action bar in Android, is a special
kind of toolbar that’s used for branding, navigation, search, and
actions.
So, you need to add a CollapsingToolbarLayout and the contents on it.
And:
I'd like to have a content area below my Toolbar. Its behavior should
be to scroll while scrolling up and to enter immediately while
scrolling down, Toolbar should stay on its place without any
scrolling.
To not to scrolling the Toolbar after adding that CollapsingToolbarLayout, you may want to add app:layout_collapseMode="pin" to that Toolbar.

Update:
Since my original suggestion did not work, another method to achieve the desired outcome would be to break out the Toolbar from the CoordinatorLayout. You can structure your layout XML as follows:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
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:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<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" />
<android.support.design.widget.CoordinatorLayout
android:id="#+id/coordinator_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ui.MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:theme="#style/AppTheme.AppBarOverlay">
<RelativeLayout
android:id="#+id/box_search"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:layout_marginBottom="16dp"
app:layout_scrollFlags="scroll|enterAlways">
<TextView
android:id="#+id/text_search_filter"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Line 1"
android:textColor="#FFF" />
<TextView
android:id="#+id/text_search_category"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/text_search_filter"
android:text="Line 2"
android:textColor="#FFF" />
<TextView
android:id="#+id/text_search_location"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/text_search_category"
android:text="Line 3"
android:textColor="#FFF" />
</RelativeLayout>
</android.support.design.widget.AppBarLayout>
<include layout="#layout/content_main"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="#dimen/fab_margin"
android:src="#drawable/ic_add_white_24dp" />
</android.support.design.widget.CoordinatorLayout>
</LinearLayout>
If it's still not working, you should consider not using the include statement as this might be the source of the issues. Rather, bring in the layout definition directly into this layout and place under a NestedScrollView (apply app:layout_behavior="#string/appbar_scrolling_view_behavior" to this NestedScrollView). If you need additional help, post the contents of your content_main layout XML in your OP.
Original Response:
Make sure you define the app:layout_behavior for your main content, which defines that the scrolling of the main content should affect the AppBarLayout. Specifically, try this:
<include layout="#layout/content_main"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />

RecyclerView and Toolbar, can't scroll bottom item into view

EDIT: See Using the Master/Detail template in ViewPager Fragments (download link) for full code
I have a toolbar and a recyclerView. When the layout is first inflated the last item of the recyclerView is out of the scroll-able region of the screen and is therefore not visible. After rotating the item appears. It is apparent that the toolbar is pushing the recyclerView outside the boundaries of the screen. If I add padding to the bottom of the recyclerView with the height of the toolbar the issue is resolved BUT only for the initial inflation of the layout. After rotation I am left with a gap on the bottom of the screen. I'm using sdk 23.
A possible workaround would be to programmatically remove the padding after the very first inflation of the layout. I assume I could use:
onCreateView(){ if (onSaveInstanceState != null) removePadding();}
However, I'd rather not have to do a dodgy work-around.
My app is basically exactly the same as the Master/Detail-flow template supplied in Android Studio, except that I use fragments and a single Activity. There is no such issue in the template.
Any ideas?
fragment_item_list.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<android.support.design.widget.AppBarLayout
android:id="#+id/app_bar"
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"
app:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<FrameLayout
android:id="#+id/frameLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<include layout="#layout/item_list" />
</FrameLayout>
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="#dimen/fab_margin"
android:src="#android:drawable/ic_dialog_email" />
</android.support.design.widget.CoordinatorLayout>
item_list.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView 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/item_list"
android:name="com.idragonit.scrolltabs.ItemListFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
app:layoutManager="LinearLayoutManager"
tools:context="com.idragonit.scrolltabs.ItemListActivity"
tools:listitem="#layout/item_list_content" />
item_list_content.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#+id/id"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/text_margin"
android:textAppearance="?attr/textAppearanceListItem" />
<TextView
android:id="#+id/content"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/text_margin"
android:textAppearance="?attr/textAppearanceListItem" />
</LinearLayout>
snippet of ItemListFragment.java
Toolbar toolbar = (Toolbar) root.findViewById(R.id.toolbar);
toolbar.setTitle("List");

I added:
android:layout_gravity="fill_vertical"
android:layout_marginBottom="?attr/actionBarSize"
to item_list.xml. The issue persists. The first time the layout is inflated it shows the bottom element as expected. After rotating to landscape and back to portrait it leaves a margin the size of the actionBar at the bottom of the screen.
This issue does not happen in the Master/Detail-flow template available in Android Studio and the code for item_list.xml, item_list_twopane.xml and activity_item_list are exactly the same as the code used in item_list.xml, land/item_list.xml and fragment_item_list.xml in my project. Yet, as the attached images show, the preview of the AppBar shows the flexible space in the Android template but not my code.
EDIT: When I click on the reference for "?attr/actionBarSize" in the template it navigates to a different line in android SDK's values.xml, which starts with <declare-styleable name="AppCompatTheme">. The same line of code in my app references a different line starting with<declare-styleable name="Theme">.
Screenshots:

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
xmlns: android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/white"
android:orientation="vertical">
<android.support.design.widget.AppBarLayout
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:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<android.support.v7.widget.RecyclerView
android:id="#+id/item_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="5dp"
android:scrollbars="vertical" />
</LinearLayout>
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_gravity="bottom|right"
android:layout_marginBottom="#dimen/activity_vertical_margin"
android:layout_marginRight="#dimen/activity_horizontal_margin"
android:src="#drawable/ic_add"
app:backgroundTint="#color/colorPrimary" />
</android.support.design.widget.CoordinatorLayout>

You must add
android:layout_paddingBottom="?attr/actionBarSize
Instead of
android:layout_marginBottom="?attr/actionBarSize
This works for me