title: DrawerLayout issue
body: <p>Good morning all,
  I'm trying out Android Studio and I want to create an app including a Google Maps and a side menu.</p>
  
  <p>At first I integrated the card that works perfectly but wanting to integrate the sidebar I run into a problem in my main XML file.</p>
  
  <p>I do not understand the errors because the so-called missing elements are present</p>
  
  <p>I am enclosing all the errors and the XML file in question</p>
  
  <p>Thank you in advance for your help !</p>
  
  <p>All Errors --></p>
  
  <pre><code>java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.platdujourproject/com.example.platdujourproject.MainActivity}: android.view.InflateException: Binary XML file line #8: Binary XML file line #8: You must supply a layout_width attribute.
      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646)
      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
      at android.app.ActivityThread.-wrap12(ActivityThread.java)
      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
      at android.os.Handler.dispatchMessage(Handler.java:102)
      at android.os.Looper.loop(Looper.java:154)
      at android.app.ActivityThread.main(ActivityThread.java:6077)
      at java.lang.reflect.Method.invoke(Native Method)
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)
   Caused by: android.view.InflateException: Binary XML file line #8: Binary XML file line #8: You must supply a layout_width attribute.
   Caused by: java.lang.UnsupportedOperationException: Binary XML file line #8: You must supply a layout_width attribute.
      at android.content.res.TypedArray.getLayoutDimension(TypedArray.java:765)
      at android.view.ViewGroup$LayoutParams.setBaseAttributes(ViewGroup.java:7059)
      at android.view.ViewGroup$MarginLayoutParams.&lt;init&gt;(ViewGroup.java:7241)
      at androidx.constraintlayout.widget.ConstraintLayout$LayoutParams.&lt;init&gt;(ConstraintLayout.java:2649)
      at androidx.constraintlayout.widget.ConstraintLayout.generateLayoutParams(ConstraintLayout.java:1972)
      at androidx.constraintlayout.widget.ConstraintLayout.generateLayoutParams(ConstraintLayout.java:482)
      at android.view.LayoutInflater.rInflate(LayoutInflater.java:860)
      at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:821)
      at android.view.LayoutInflater.inflate(LayoutInflater.java:518)
      at android.view.LayoutInflater.inflate(LayoutInflater.java:426)
      at android.view.LayoutInflater.inflate(LayoutInflater.java:377)
      at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:555)
      at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:161)
      at com.example.platdujourproject.MainActivity.onCreate(MainActivity.java:52)
      at android.app.Activity.performCreate(Activity.java:6662)
      at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599)
      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
      at android.app.ActivityThread.-wrap12(ActivityThread.java)
      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
      at android.os.Handler.dispatchMessage(Handler.java:102)
      at android.os.Looper.loop(Looper.java:154)
      at android.app.ActivityThread.main(ActivityThread.java:6077)
      at java.lang.reflect.Method.invoke(Native Method)
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)
  </code></pre>
  
  <p>Activity_main.xml --></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;androidx.constraintlayout.widget.ConstraintLayout 
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  tools:context=".MainActivity"&gt;
  
  &lt;androidx.drawerlayout.widget.DrawerLayout
      xmlns:android="https://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto"
      android:id="@+id/drawer_layout"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      tools:openDrawer="start"&gt;
  
      &lt;include
          layout="@layout/app_bar_main"
          android:layout_width="match_parent"
          android:layout_height="match_parent" /&gt;
  
      &lt;android.support.design.widget.NavigationView
          android:id="@+id/nav_view"
          android:layout_width="wrap_content"
          android:layout_height="match_parent"
          android:layout_gravity="start"
          app:headerLayout="@menu/nav_header_main"
          app:menu="@menu/activity_main_drawer" /&gt;
  
  &lt;/androidx.drawerlayout.widget.DrawerLayout&gt;
  
  &lt;fragment
      android:id="@+id/map"
      android:name="com.google.android.gms.maps.SupportMapFragment"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      tools:context="com.example.dell.displayinggooglemaps.MapsActivity" /&gt;
  &lt;/androidx.constraintlayout.widget.ConstraintLayout&gt;
  </code></pre>
  
  <p>app_bar_main.xml --></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;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=".MainActivity"&gt;
  
      &lt;android.support.design.widget.AppBarLayout
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:fitsSystemWindows="true"
          android:theme="@style/ThemeOverlay.AppCompat.Dark"&gt;
  
          &lt;android.support.v7.widget.Toolbar
              android:id="@+id/toolbar_main"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:background="?attr/colorPrimary"
              app:layout_scrollFlags="scroll|enterAlways"
              app:popupTheme="@style/ThemeOverlay.AppCompat.Dark" /&gt;
  
      &lt;/android.support.design.widget.AppBarLayout&gt;
  &lt;/android.support.design.widget.CoordinatorLayout&gt;
  </code></pre>
  
  <p>activity_main_drawer.xml --></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;menu xmlns:android="http://schemas.android.com/apk/res/android"&gt;
      &lt;group android:id="@+id/group_menu"&gt;
          &lt;item android:id="@+id/nav_item_four"
              android:title="Item 4" /&gt;
          &lt;item android:id="@+id/nav_item_five"
              android:title="Item 5" /&gt;
      &lt;/group&gt;
  
      &lt;item android:title="Title 1"&gt;
          &lt;menu&gt;
              &lt;item android:id="@+id/nav_item_six"
  
                  android:title="Item 6" /&gt;
              &lt;item android:id="@+id/nav_item_seven"
                  android:title="Item 7" /&gt;
          &lt;/menu&gt;
      &lt;/item&gt;
  &lt;/menu&gt;
  </code></pre>
  
  <p>nav_header_main.xml --></p>
  
  <pre><code>&lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/nav_header"
      android:layout_width="match_parent"
      android:layout_height="160dp"
      android:background="@color/colorAccent"
      android:clickable="true"
      android:focusable="true"
      android:foreground="?attr/selectableItemBackgroundBorderless"
      android:gravity="bottom"
      android:orientation="vertical"
      android:padding="16dp"
      android:theme="@style/ThemeOverlay.AppCompat.Dark"&gt;
  
      &lt;ImageView
          android:id="@+id/nav_header_imageView"
          android:layout_width="64dp"
          android:layout_height="64dp"
          android:src="@mipmap/ic_launcher" /&gt;
  
      &lt;TextView
          android:id="@+id/nav_header_textView"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:paddingTop="16dp"
          android:text="Chike Mgbemena"
          android:textAppearance="@style/TextAppearance.AppCompat.Body1" /&gt;
  &lt;/LinearLayout&gt;
  </code></pre>