title: Android activity design with layouts
body: <p>I have to create Android activity which looks like this:</p>
  
  <p><a href="https://i.stack.imgur.com/RhOT4.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/RhOT4.png" alt="enter image description here"></a></p>
  
  <p>Now I've created only such part of the activity.</p>
  
  <p><a href="https://i.stack.imgur.com/QQwae.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QQwae.png" alt="enter image description here"></a></p>
  
  <p>Which coded this way.</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;android.support.constraint.ConstraintLayout
      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="ru.alexeyzhulin.elecomp.MainActivity"&gt;
  
      &lt;LinearLayout
          android:layout_width="fill_parent"
          android:layout_height="fill_parent"
          android:orientation="vertical"
          tools:layout_editor_absoluteX="0dp"
          tools:layout_editor_absoluteY="0dp"&gt;
  
          &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="fill_parent"
                  android:orientation="horizontal"&gt;
  
                  &lt;ImageButton
                      android:id="@+id/logoButton"
                      android:layout_width="55dp"
                      android:layout_height="55dp"
                      android:layout_weight="0"
                      android:background="@color/colorPrimary"
                      app:srcCompat="@drawable/main_icon" /&gt;
  
                  &lt;SearchView
                      android:id="@+id/searchText"
                      android:layout_width="wrap_content"
                      android:layout_height="55dp"
                      android:layout_weight="1"
                      android:background="@color/colorPrimary"
                      android:queryHint="@string/search_message"
                      android:textAlignment="center" /&gt;
  
                  &lt;ImageButton
                      android:id="@+id/cartButton"
                      android:layout_width="55dp"
                      android:layout_height="55dp"
                      android:layout_weight="0"
                      android:background="@color/colorPrimary"
                      app:srcCompat="@drawable/cart_icon1" /&gt;
              &lt;/LinearLayout&gt;
  
      &lt;/LinearLayout&gt;
  &lt;/android.support.constraint.ConstraintLayout&gt;
  </code></pre>
  
  <p>Please help me how to put last four buttons to the activity.</p>
  
  <p>The particular question is:</p>
  
  <p>How to put four buttons in the center of the screen.</p>