android - Error inflating class - NestedScrollView - class not found

Question

Running Android Studio 2.1.2, Windows 7.

I replaced a ScrollView with a NestedScrollView and now I'm getting

android.view.InflateException: Binary XML file line #2: Error inflating class NestedScrollView

java.lang.ClassNotFoundException: Didn't find class "android.view.NestedScrollView" on path: /data/app/com.assemblyguide.remote-48.apk

... when I call SetContentView() on that XML file. I did not get it when I had just a ScrollView.

I've tried cleaning, and invalidating the cache and rebuilding. The XML looks like this . . .

<?xml version="1.0" encoding="utf-8"?>
<NestedScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <!-- This linear layout is because the scrollview can have only 1 direct child -->
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical" >

        <!-- Relative layout for Workorder -->
        <RelativeLayout
            android:id="@+id/rellayWorkorder"
            android:background="#383838"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="30dp"
            android:layout_marginBottom="2dp">
            <TextView
                android:id="@+id/workorderlabel"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="true"
                android:layout_margin="2dp"
                android:gravity="left"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="Work Order:"/>

            <TextView
                android:id="@+id/workorderContent"
                android:layout_width="150dp"
                android:layout_height="wrap_content"
                android:layout_alignParentRight="true"
                android:layout_margin="2dp"
                android:gravity="right"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="---workorder---"/>
        </RelativeLayout>


        <!-- Relative layout for Required Time
   <FrameLayout
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:layout_gravity="center_horizontal"></FrameLayout> -->

        <RelativeLayout
            android:id="@+id/rellayRequiredTime"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="30dp"
            android:layout_marginBottom="2dp">
            <TextView
                android:id="@+id/requiredTimelabel"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="true"
                android:layout_margin="2dp"
                android:gravity="left"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="Required Time:"/>

            <TextView
                android:id="@+id/requiredTimeContent"
                android:layout_width="150dp"
                android:layout_height="wrap_content"
                android:layout_alignParentRight="true"
                android:layout_margin="2dp"
                android:gravity="right"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="--- 00 minutes ---"/>
        </RelativeLayout>

        <!-- Relative layout for Time remaining -->
        <RelativeLayout
            android:id="@+id/rellayTimeRemaining"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="30dp"
            android:layout_marginBottom="2dp">
            <TextView
                android:id="@+id/timeremaininglabel"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="true"
                android:layout_margin="2dp"
                android:gravity="left"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="Time Remaining:"/>

            <TextView
                android:id="@+id/tviewtimeremainingContent"
                android:layout_width="150dp"
                android:layout_height="wrap_content"
                android:layout_alignParentRight="true"
                android:layout_margin="2dp"
                android:gravity="right"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="--- 0:00:00---"/>
        </RelativeLayout>

        <!--  Linear layout for Record Start / Record End buttons -->
        <LinearLayout
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"  >
            <Button
                android:id="@+id/debulkrecordStart"
                android:layout_width="150dp"
                android:layout_height="wrap_content"
                android:layout_marginTop="6dp"
                android:layout_marginRight="4dp"
                android:gravity="center"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:onClick="OnSetRecordStartTimeClick"
                android:text="Record Start"/>
            <Button
                android:id="@+id/debulkrecordEnd"
                android:layout_width="150dp"
                android:layout_height="wrap_content"
                android:layout_marginTop="6dp"
                android:layout_marginRight="4dp"
                android:gravity="center"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:onClick="OnSetRecordEndTimeClick"
                android:text="Record End"/>
        </LinearLayout>

        <!-- Relative layout for Vacuum level -->
        <RelativeLayout
            android:id="@+id/rellayvacuumlevel"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="2dp">
            <TextView
                android:id="@+id/vaclabel"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="true"
                android:layout_margin="2dp"
                android:gravity="left"
                android:textAppearance="?android:attr/textAppearanceSmall"
                android:text="Vacuum Level (inches Hg):"/>
            <EditText
                android:id="@+id/vacleveledit"
                android:layout_width="120dp"
                android:layout_height="wrap_content"
                android:layout_alignParentRight = "true"
                android:layout_margin="2dp"
                android:gravity="left"
                android:textAppearance="?android:attr/textAppearanceSmall"
                android:inputType="text|textCapCharacters"
                android:text="vac level"
                android:layout_marginRight="2dp"
                android:layout_marginTop="2dp"
                android:layout_marginBottom="2dp"/>
        </RelativeLayout>

        <!-- Relative layout for Vac Gauge Equipment # -->
        <RelativeLayout
            android:id="@+id/rlayvacuumGauge"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="2dp">
            <TextView
                android:id="@+id/vacgaugelabel"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="true"
                android:layout_margin="2dp"
                android:gravity="left"
                android:textAppearance="?android:attr/textAppearanceSmall"
                android:text="Vac Gauge Equipment #:"/>
            <EditText
                android:id="@+id/vacgaugeedit"
                android:layout_width="120dp"
                android:layout_height="wrap_content"
                android:layout_alignParentRight = "true"
                android:layout_margin="2dp"
                android:gravity="left"
                android:textAppearance="?android:attr/textAppearanceSmall"
                android:inputType="text|textCapCharacters"
                android:text="equip. #"/>
        </RelativeLayout>



        <!-- Relative layout for Calibration Due date -->
        <RelativeLayout
            android:id="@+id/rlaycalibdue"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="2dp">
            <TextView
                android:id="@+id/calibduelabel"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="true"
                android:layout_margin="2dp"
                android:gravity="left"
                android:textAppearance="?android:attr/textAppearanceSmall"
                android:text="Calibration Due Date:"/>
            <EditText
                android:id="@+id/calibdueedit"
                android:layout_width="120dp"
                android:layout_height="wrap_content"
                android:layout_alignParentRight = "true"
                android:layout_margin="2dp"
                android:gravity="left"
                android:textAppearance="?android:attr/textAppearanceSmall"
                android:inputType="text|textCapCharacters"
                android:text="mm/dd/yyyy"/>
        </RelativeLayout>


        <CalendarView
            android:id="@+id/debulkcalendar"
            android:layout_width="300dp"
            android:layout_height="250dp"
            android:minDate="01/01/2016"
            android:maxDate="11/30/2016"
            />


        <!--  this linear layout is for the debulk override and done buttons  -->
        <LinearLayout
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"  >
            <Button
                android:id="@+id/debulkOverride"
                android:layout_width="150dp"
                android:layout_height="wrap_content"
                android:layout_marginTop="6dp"
                android:layout_marginRight="4dp"
                android:onClick="OnResetClick"
                android:gravity="center"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="Override"/>
            <Button
                android:id="@+id/debulkDone"
                android:layout_width="150dp"
                android:layout_height="wrap_content"
                android:layout_marginTop="6dp"
                android:layout_marginRight="2dp"
                android:onClick="onDoneBtnClick"
   

Answer 1

The full class name is android.support.v4.widget.NestedScrollView. Replace the <NestedScrollView> element with <android.support.v4.widget.NestedScrollView> and it should work fine. Make sure you have the v4 support library in your build.gradle file, too.