App keep getting stopped because of Floating Action Button

Question

My app keep getting stopped after launching it on my mobile connecting it to android studio.

Below is my Log file which shows following error.Basically what i understood is that error is because of floating action button that i am using in my main_activity.xml file

I am not able to figure it out what exactly is causing the error. I have even added library 'com.android.support:design:26.1.0'.

05-11 11:18:01.098 27456-27456/it.moondroid.chatbot E/AndroidRuntime: FATA          L EXCEPTION: main
         Process: it.moondroid.chatbot, PID: 27456
        java.lang.RuntimeException: Unable to start activity ComponentInfo{it.moondroid.chatbot/it.moondroid.chatbot.MainActivity}: android.view.InflateException: Binary XML file line #39: Binary XML file line #39: Error inflating class android.support.design.widget.FloatingActionButton
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2957)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3032)
        at android.app.ActivityThread.-wrap11(Unknown Source:0)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1696)
        at android.os.Handler.dispatchMessage(Handler.java:105)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:6940)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)
     Caused by: android.view.InflateException: Binary XML file line #39: Binary XML file line #39: Error inflating class android.support.design.widget.FloatingActionButton
     Caused by: android.view.InflateException: Binary XML file line #39: Error inflating class android.support.design.widget.FloatingActionButton
     Caused by: java.lang.reflect.InvocationTargetException
        at java.lang.reflect.Constructor.newInstance0(Native Method)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:334)
        at android.view.LayoutInflater.createView(LayoutInflater.java:647)
        at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:790)
        at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
        at android.view.LayoutInflater.rInflate(LayoutInflater.java:863)
        at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
        at android.view.LayoutInflater.rInflate(LayoutInflater.java:866)
        at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
        at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
        at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
        at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
        at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:461)
        at android.app.Activity.setContentView(Activity.java:2737)
        at it.moondroid.chatbot.MainActivity.onCreate(MainActivity.java:47)
        at android.app.Activity.performCreate(Activity.java:7174)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1220)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2910)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3032)
        at android.app.ActivityThread.-wrap11(Unknown Source:0)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1696)
        at android.os.Handler.dispatchMessage(Handler.java:105)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:6940)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)
     Caused by: java.lang.IllegalArgumentException: You need to use a Theme.AppCompat theme (or descendant) with the design library.
        at android.support.design.widget.ThemeUtils.checkAppCompatTheme(ThemeUtils.java:33)
        at android.support.design.widget.FloatingActionButton.<init>(FloatingActionButton.java:157)
        at android.support.design.widget.FloatingActionButton.<init>(FloatingActionButton.java:151)
        at java.lang.reflect.Constructor.newInstance0(Native Method) 
        at java.lang.reflect.Constructor.newInstance(Constructor.java:334) 
        at android.view.LayoutInflater.createView(LayoutInflater.java:647) 
        at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:790) 
        at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730) 
        at android.view.LayoutInflater.rInflate(LayoutInflater.java:863) 
        at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824) 
        at android.view.LayoutInflater.rInflate(LayoutInflater.java:866) 
        at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824) 
        at android.view.LayoutInflater.inflate(LayoutInflater.java:515) 
        at android.view.LayoutInflater.inflate(LayoutInflater.java:423) 
        at android.view.LayoutInflater.inflate(LayoutInflater.java:374) 
        at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:461) 
        at android.app.Activity.setContentView(Activity.java:2737) 
        at it.moondroid.chatbot.MainActivity.onCreate(MainActivity.java:47) 
        at android.app.Activity.performCreate(Activity.java:7174) 
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1220) 
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2910) 
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3032) 
        at android.app.ActivityThread.-wrap11(Unknown Source:0) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1696) 
        at android.os.Handler.dispatchMessage(Handler.java:105) 
        at android.os.Looper.loop(Looper.java:164) 
        at android.app.ActivityThread.main(ActivityThread.java:6940) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)

Below here i my xml File

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/background_hd" >

    <ListView
        android:id="@+id/chat_listView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_above="@+id/form"
        android:layout_alignParentTop="true"
        android:clipToPadding="false"
        android:divider="@android:color/transparent"
        android:dividerHeight="1dp"
        android:listSelector="@android:color/transparent"
        android:transcriptMode="alwaysScroll" >
    </ListView>

    <RelativeLayout
        android:id="@+id/form"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentStart="true"
        android:background="@android:color/white"
        android:padding="16dp">

        <EditText
            android:id="@+id/chat_editText"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_alignParentRight="true"
            android:layout_marginRight="82dp"
            android:inputType="text" />

        <android.support.design.widget.FloatingActionButton
            android:id="@+id/btn"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentEnd="true"
            android:layout_centerVertical="true"
            android:layout_marginEnd="13dp"
            android:clickable="true"
            android:focusable="true"
            android:src="@android:drawable/ic_btn_speak_now"
            app:fabSize="mini" />

        </RelativeLayout>

    </RelativeLayout>

Answer 1

As stated in Error log " You need to use a Theme.AppCompat theme (or descendant) with the design library".

Thanks