Develop Reference

Floating Button showed too low - placed in CoordinatorLayout with android:layout_gravity="bottom|end"

my floating action button shows up too low, even though it looks just fine in the Android Studio preview (see below).
FB is placed in root under CoordinatorLayout and set to show at the bottom end using android:layout_gravity.
This Layout is used in Fragment (extends Fragment) with Tabbed Activity using ViewPager. Android X.
Thanks
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/fragmentTableCoordinator"
tools:context=".fragment.FragmentTable">
<!-- CoordinatorLayout for Floating Button -->
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/fragmentTable"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/colorBackgroundCards">
<!-- Total Card -->
<androidx.cardview.widget.CardView
android:id="#+id/card_viewNew"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="5dp"
card_view:cardCornerRadius="2dp"
card_view:contentPadding="10dp"
card_view:layout_constraintEnd_toEndOf="parent"
card_view:layout_constraintStart_toStartOf="parent"
card_view:layout_constraintTop_toTopOf="parent">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="fill_parent"
android:layout_height="match_parent">
<androidx.constraintlayout.widget.Guideline
android:id="#+id/Total_guideline"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
card_view:layout_constraintGuide_percent="0.5" />
<!-- some textViews here -->
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.cardview.widget.CardView>
<!-- RecyclerView with months -->
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/Total_recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
android:scrollbars="vertical"
android:visibility="visible"
card_view:layout_constraintEnd_toEndOf="parent"
card_view:layout_constraintStart_toStartOf="parent"
card_view:layout_constraintTop_toBottomOf="#+id/card_viewNew" />
</androidx.constraintlayout.widget.ConstraintLayout>
<!-- Floating button -->
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/floating_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="#dimen/fab_margin"
android:contentDescription="TODO"
app:srcCompat="#android:drawable/ic_dialog_email" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>

My own fix : after hours trying to fix in in Fragment Layout - the best for me worked :
place Floating button into activity_main layout
hide it (setVisibility) for Fragment you dont need.
This solved this for me

You're setting ConstraintLayout inside the CoordinatorLayout and also CoordinatorLayout in the Fragment layout. You'll need to change it a bit.
Use FloatingActionButton inside your main activity layout with CoordinatorLayout, AppBarLayout and maybe a NestedScrollView, use ConstraintLayout in your Fragment layout and then, as you already mentioned, you'll be able to see FloatingActionButton with desire effect which is also stable at the bottom of the page and then you can hide it in the Fragments you don't want to use.

Android How to center title of top actionBar?

To start my objective is to center my title. I have started a project by selecting the bottom navigation activity template. This came with 3 fragments and a main activity. I am attempting to center the title of the top action bar. I have attempted to access the mobile_navigation by id and align the text within the MainActivity but this does not seem to work. I also tried adding a textAlignment attribute in the homeFragment.xml but this did not work either. I do not find any similar scenarios anyone know how could I be able to resolve this?
mobile_navigation.xml:
<?xml version="1.0" encoding="utf-8"?>
<navigation 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/mobile_navigation"
app:startDestination="#+id/navigation_home">
<fragment
android:id="#+id/navigation_home"
android:name="com.Example.exmaple.ui.home.HomeFragment"
android:label="#string/app_name"
tools:layout="#layout/fragment_home" />
<fragment
android:id="#+id/navigation_dashboard"
android:name="com.Example.exmaple.ui.dashboard.DashboardFragment"
android:label="#string/title_dashboard"
tools:layout="#layout/fragment_dashboard" />
<fragment
android:id="#+id/navigation_notifications"
android:name="com.Example.exmaple.ui.notifications.NotificationsFragment"
android:label="#string/title_notifications"
tools:layout="#layout/fragment_notifications" />
</navigation>
I also attempted to add:
android:gravity="center"
Any feedback welcomed.

To use a custom title in your Toolbar all you need to do is remember is that Toolbar is just a fancy ViewGroup so you can add a custom title like so:
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar_top"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:minHeight="?attr/actionBarSize"
android:background="#color/action_bar_bkgnd"
app:theme="#style/ToolBarTheme" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Toolbar Title"
android:layout_gravity="center"
android:id="#+id/toolbar_title" />
</android.support.v7.widget.Toolbar>
This means that you can style the TextView however you would like because it's just a regular TextView. So in your activity you can access the title like so:
Toolbar toolbarTop = (Toolbar) findViewById(R.id.toolbar_top);
TextView mTitle = (TextView) toolbarTop.findViewById(R.id.toolbar_title);
setSupportActionBar(toolbar);
mTitle.setText(toolbar.getTitle());
getSupportActionBar().setDisplayShowTitleEnabled(false);

Try below code may works for you
getSupportActionBar().setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
getSupportActionBar().setCustomView(R.layout.abs_layout);

Better add a layout file for tool bar and center the title there and add dynamically on create or include in your fragment layout file.

I was able to figure out the solution. I will post it incase anyone runs across this issue.
I added the following to the Main Activity xml:
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolBar"
android:elevation="5dp"
app:layout_constraintTop_toTopOf="parent"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/colorBlack">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#color/colorTransparent"
android:layout_alignParentStart="true"
android:layout_gravity="start"
android:text="#string/log_out"
android:textAlignment="center"
android:textColor="#color/lightblue"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/app_name"
android:textColor="#color/colorApp"
android:textSize="20sp"/>
<ImageButton
android:layout_width="20dp"
android:layout_height="20dp"
android:src="#drawable/ic_add"
android:tint="#color/lightblue"
android:layout_alignParentEnd="true"
android:layout_gravity="end"
android:background="#color/colorBlack" />
</androidx.appcompat.widget.Toolbar>
I also took away the padding top from the androidx.constraintlayout.widget.ConstraintLayout opening tag in the Main Activity XML
Added the following style to styles.xml:
<style name="AppTheme.NoActionBar" parent="AppTheme">
<item name="windowNoTitle">true</item>
<item name="windowActionBar">false</item>
</style>
Finally in the Android manifest I added the following theme to the Main Acivity:
android:theme="#style/AppTheme.NoActionBar"

Bring to Button front while having two ConstraintLayout

I'm trying to implement the following design on Android.
I know that to have the button at that position I should have two constraint layout; one for whole change password form and one for change password form without the Save button and then set the Save button's Top and Bottom constraint to the second ConstraintLayout.
But when I do this, the button goes behind the form, and therein lies the problem:
Here is my XML:
<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"
tools:context=".ChangePasswordActivity">
<include
android:id="#+id/changePasswordBar"
layout="#layout/top_bar_full"></include>
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<android.support.constraint.ConstraintLayout
android:id="#+id/changePasswordCTL"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="#dimen/activities_constraint_top_bottom"
android:layout_marginEnd="#dimen/activities_constraint_start_end"
android:layout_marginStart="#dimen/activities_constraint_start_end"
android:layout_marginTop="#dimen/activities_constraint_top_bottom"
android:background="#drawable/radius_background_exchange"
android:elevation="5dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
// some EditText and TextView views here
</android.support.constraint.ConstraintLayout>
<br.com.simplepass.loading_button_lib.customViews.CircularProgressButton
android:id="#+id/changePasswordBT"
style="#style/customButton"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:layout_marginEnd="32dp"
android:layout_marginStart="32dp"
android:layout_marginTop="8dp"
android:fontFamily="#font/sans_web_medium"
android:text="#string/finish"
android:textAllCaps="false"
android:textColor="#android:color/white"
android:textSize="#dimen/signinup_button_font_size"
app:initialCornerAngle="5dp"
app:layout_constraintBottom_toBottomOf="#+id/changePasswordCTL"
app:layout_constraintEnd_toEndOf="#+id/changePasswordCTL"
app:layout_constraintStart_toStartOf="#+id/changePasswordCTL"
app:layout_constraintTop_toBottomOf="#+id/changePasswordCTL"
app:spinning_bar_color="#android:color/white"
app:spinning_bar_padding="6dp"
app:spinning_bar_width="4dp" />
</android.support.constraint.ConstraintLayout>
</android.support.design.widget.CoordinatorLayout>

When elevation isn't in the picture, views that are defined later in the XML file will draw "on top" of views defined earlier. However, your password form has android:elevation="5dp", and this will override the normal drawing order.
To fix, add elevation to the button as well. android:elevation="5dp" should be enough, since then they're at the same elevation and the normal rules should apply. But you could give it more elevation to guarantee that it always draws on top of the password form.

There is a 5dp elevation on the form and no elevation on the button, so it is partially obscured. Increase the button elevation to at least 5dp.
android:elevation="5dp"

You could achieve such design by using a CoordinatorLayout.
Example:
<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:fitsSystemWindows="true">
<ImageView
android:id="#+id/header"
android:layout_width="match_parent"
android:layout_height="180dp"
android:adjustViewBounds="true"
android:scaleType="centerCrop"
android:background="#color/primary" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ic_camera"
app:layout_anchor="#id/header"
app:layout_anchorGravity="bottom|center_horizontal" />
</android.support.design.widget.CoordinatorLayout>
just use the following to anchor the layout of your button to the layout of your library view:
app:layout_anchor= "id_of_password_form_layout"

How can I add a shadow to bottom sheet view?

As of now, with the official bottom sheet component from the Android design library implemented the top edge doesn't show a shadow. But for what I've seen in various mockups and in the Material Design specs, the bottom sheet include a discrete shadow of some sort.
I think the shadow would help distant the bottom sheet from the main layout, especially if there's a peek value set and/or the bottom sheet is always visible. Otherwise it just will blend together with the main layout and its items.
I've tried both ViewCompat.setElevation(bottomSheet, 5); and setting android:elevation="5dp" to the view in the XML, without success.

I know that a shadow shape doesn't have the same appearance as an elevation - but at least give it a try. The trick is to use app:layout_anchor to clip the shadow to the bottom sheet.
activity_main.xml
<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">
<MapView
android:id="#+id/map"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<View
android:id="#+id/shadow"
android:layout_width="match_parent"
android:layout_height="16dp"
android:background="#drawable/shape_gradient_top_shadow"
app:layout_anchor="#id/bottom_sheet" />
<FrameLayout
android:id="#+id/bottom_sheet"
android:layout_width="match_parent"
android:layout_height="200dp"
android:clipToPadding="false"
app:layout_behavior="android.support.design.widget.BottomSheetBehavior" />
</android.support.design.widget.CoordinatorLayout>
shape_gradient_top_shadow.xml
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<gradient
android:angle="90"
android:endColor="#android:color/transparent"
android:startColor="#64000000"/>
</shape>
Looks like this:
EDIT
Get an even better result with a custom ShadowView:
Post from Roman Nurik on this topic: https://plus.google.com/+RomanNurik/posts/2QvHVFWrHZf
Gist of the ShadowView based on Roman Nurik's solution: https://gist.github.com/MariusBoepple/bf869e02541cd4750550e88fa07b5ddd
Then you can do the following:
<ShadowView
android:id="#+id/shadow"
android:layout_width="match_parent"
android:layout_height="16dp"
android:gravity="bottom"
app:layout_anchor="#id/bottom_sheet" />

For API Level 21 and higher, set the following in the parent view. You can also try in the rootview of the bottomsheet (I have not tried it in the root view)
android:background="#android:color/white"
android:elevation="16dp"
If no background then can use
android:outlineProvider="bounds"
For example, I have my sheet inside a nested scroll view
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clipToPadding="false"
app:layout_behavior="android.support.design.widget.BottomSheetBehavior"
android:elevation="16dp"
android:outlineProvider="bounds"
>
<include layout="#layout/bottomsheet_1" />
</android.support.v4.widget.NestedScrollView>

The trick is to use a CardView as parent and set the elevation in the CardView
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:background="#fff"
android:clickable="true"
android:focusable="true"
app:behavior_hideable="true"
app:layout_behavior="android.support.design.widget.BottomSheetBehavior"
android:layout_height="140dp"
app:cardElevation="8sp"
card_view:cardCornerRadius="0dp">
<!--The content of your Bottom sheet-->
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
.
.
</android.support.constraint.ConstraintLayout>
</android.support.v7.widget.CardView>
EDIT
This technique is not the best solution if you are supporting Kitkat and below. It's due to the extra margin added by the Cardview.

I think this will help you
first create bottom sheet like bellow then include in your main activity
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/bottom_sheet"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
app:behavior_hideable="true"
app:behavior_peekHeight="56dp"
android:layout_marginTop="0.5dp" // this margin depend on shadow area
android:background="set you color"
android:elevation="20dp" // chose your custom elevation
app:layout_behavior="#string/bottom_sheet_behavior">
<LinearLayout
android:layout_marginTop="1dp" // this margin depend on max elevation
android:layout_width="match_parent"
android:layout_height="200dp">
</LinearLayout>
</LinearLayout>

How can I place a ProgressBar at the right of the Toolbar?

With the new Lollipop API, we have to use a Toolbar if we want to personalize the action bar aspect.
Adding a ProgressBar to the Toolbar is as simple as adding it to the Toolbar ViewGroup, as Chris Banes said.
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/material_green_500"
android:minHeight="?attr/actionBarSize"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
app:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<!-- Color is Brown 500 -->
<ProgressBar
android:id="#+id/toolbar_progress_bar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:indeterminateTint="#795548"
android:indeterminateTintMode="src_in"/>
</android.support.v7.widget.Toolbar>
But how can we place it at the right of the Toolbar, where it belongs?
The layout_gravity attribute seems to not be defined for the Toolbar. Setting it from the xml has no effect.
I tried to change the width of the ProgressBar, with no success.
What do I do?
EDIT: There is a programmatical solution to this problem, see #mdelolmo reply for that.

You can try this. It worked for me. Key here is to define layout_gravity in the xml: android:layout_gravity="right"
<android.support.v7.widget.Toolbar
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/material_green_500"
android:minHeight="?attr/actionBarSize"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
app:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<!-- Color is Brown 500 -->
<ProgressBar
android:id="#+id/toolbar_progress_bar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:indeterminateTint="#795548"
android:indeterminateTintMode="src_in"
android:layout_gravity="right"
/>
</android.support.v7.widget.Toolbar>

I also hit the same wall, but programmatically it works:
Toolbar.LayoutParams layoutParams = new Toolbar.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT,
Gravity.TOP | Gravity.RIGHT);
In my snippet, I align it to the top, to match the alignment of the menu.

A workaround to create the layout completely in xml would be replacing the toolbar content with your own relative layout. To do that, you need to fake the activity title (and also the navigation icon if you are using one), which is literally nesting the following in your Toolbar block.
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="#dimen/toolbar_height"
android:paddingRight="2dp" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:text="#string/app_name"
android:textColor="#android:color/white"
android:textSize="20sp"
android:fontFamily="sans-serif-medium" />
<ProgressBar
android:id="#+id/toolbar_progress_bar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:indeterminateTint="#795548"
android:indeterminateTintMode="src_in" />
</RelativeLayout>
Note that 20sp sans-serif-medium is the font used in lollipop toolbar, you might need to adjust the text view parameters to make it look natural in earlier versions.