title: Center content in scroll view
body: <p>I want to center my LinearLayout within ScrollView. When LinearLayout's height is small it's centered alright (see image #1) but when LinearLayout's height is bigger than the screen's height then it behaves strange. I cannot see the top of LinearLayout (see image #2) and at the bottom of ScrollView there's huge padding. I don't know what's happening here. When there are lots of content in LinearLayout the whole screen should look like in image #3. </p>
  
  <p><a href="https://i.imgur.com/NZ7ufsJ.png" rel="noreferrer">image #1</a><br>
  <a href="https://i.imgur.com/Xopxfz6.png" rel="noreferrer">image #2</a><br>
  <a href="https://i.imgur.com/py4pUWj.png" rel="noreferrer">image #3</a><br></p>
  
  <p>Here's my layout file:</p>
  
  <pre><code>            &lt;?xml version="1.0" encoding="utf-8"?&gt;
              &lt;ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
                  android:layout_width="match_parent"
                  android:layout_height="match_parent"
                  android:background="#cccfff" &gt;
  
                  &lt;LinearLayout
                      android:layout_width="match_parent"
                      android:layout_height="wrap_content"
                      android:layout_gravity="center_vertical"
                      android:layout_margin="28dp"
                      android:background="#ffffff"
                      android:orientation="vertical"
                      android:paddingBottom="40dp"
                      android:paddingLeft="20dp"
                      android:paddingRight="20dp"
                      android:paddingTop="40dp" &gt;
  
                      &lt;ImageView
                          android:layout_width="wrap_content"
                          android:layout_height="wrap_content"
                          android:layout_marginBottom="16dp"
                          android:src="@drawable/ic_launcher" /&gt;
  
                      &lt;TextView
                          android:id="@+id/tip_title"
                          android:layout_width="wrap_content"
                          android:layout_height="wrap_content"
                          android:layout_marginBottom="12dp"
                          android:text="Title"
                          android:textColor="@color/orange_text"
                          android:textSize="@dimen/font_size_medium" /&gt;
  
                      &lt;TextView
                          android:id="@+id/tip_description"
                          android:layout_width="wrap_content"
                          android:layout_height="wrap_content"
                          android:text="Description description..."
                          android:textSize="@dimen/font_size_small" /&gt;
                  &lt;/LinearLayout&gt;
  
              &lt;/ScrollView&gt;
  </code></pre>