title: Android: issues centering text view horizontally + button text vertically
body: <p>I need to center that two information ("123456789" and "RACCOLTA PUNTI") in the screen.
  This is the (not) desidered result:</p>
  
  <p><a href="https://i.stack.imgur.com/SGLsN.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/SGLsN.png" alt="enter image description here"></a></p>
  
  <p>And this is my XML layout:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;RelativeLayout
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/dashboard_layout"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:padding="@dimen/padding_left"&gt;
  
      &lt;LinearLayout
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:orientation="vertical"&gt;
  
          &lt;TextView
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:textAppearance="@style/TextAppearance.AppCompat.Display2"
              android:id="@+id/card_number"
              android:gravity="center"/&gt;
  
          &lt;TextView
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:textAppearance="@style/TextAppearance.AppCompat.Display1"
              android:id="@+id/name_campaign"
              android:gravity="center"/&gt;
  
          &lt;View
              android:layout_width="5dp"
              android:layout_height="20dp"
              android:layout_alignWithParentIfMissing="false"
              android:layout_centerVertical="true"
              android:layout_centerHorizontal="true"
              android:id="@+id/view_anchor"
              android:gravity="center_horizontal"/&gt;
  
          &lt;Button
              android:layout_width="fill_parent"
              android:layout_height="wrap_content"
              android:text="@string/btn_add"
              android:id="@+id/button_add"
              android:gravity="center_horizontal"/&gt;
  
          &lt;Button
              android:layout_width="fill_parent"
              android:layout_height="wrap_content"
              android:text="@string/btn_deduct"
              android:id="@+id/button_deduct"
              android:gravity="center_horizontal"/&gt;
  
      &lt;/LinearLayout&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>Another one issues: you can note that text in button are not centered (vertically). How I can center (vertically) them? Thank you very much</p>