title: Why the EditText shows a black frame when focused on devices that greater than 7.0
body: <p>this is my Edittext, it works well on all the devices that below 7.0. all of the things are ok, the following capture is good.</p>
  
  <p><a href="https://i.stack.imgur.com/jYBrJ.jpg" rel="nofollow noreferrer">good man, click me</a></p>
  
  <p>but when the edittext get focus, it gets a black frame, the color became more and more black automatically, it seems like the edittext redraw but have not erased the background. To the end, it has become like the following image:</p>
  
  <p><a href="https://i.stack.imgur.com/JLyuI.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JLyuI.jpg" alt="enter image description here"></a></p>
  
  <p>so, let me summy all the clues:</p>
  
  <ol>
  <li><p>only occur greater than android 7.0</p></li>
  <li><p>the shape is rounded rectangle</p></li>
  <li><p>focused (when i touch other views, the black frame disappear, it would appear in a while later.)</p></li>
  </ol>
  
  <p>the EditText layout attribute is shown below:</p>
  
  <pre><code>&lt;EditText
      android:id="@+id/contact_type"
      android:layout_width="match_parent"
      android:layout_height="32dp"
      android:layout_marginLeft="16dp"
      android:background="@drawable/complain_edit"
      android:maxLines="1"
      android:paddingLeft="13dp"
      android:hint="@string/text_contact_number"
      android:textSize="12sp" /&gt;
  </code></pre>
  
  <p>and the @drawable/complain_edit is mention to the following lines of my code:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;shape xmlns:android="http://schemas.android.com/apk/res/android"
      android:shape="rectangle"&gt;
  
      &lt;corners
          android:bottomLeftRadius="33.33dp"
          android:bottomRightRadius="33.33dp"
          android:topLeftRadius="33.33dp"
          android:topRightRadius="33.33dp" /&gt;
  
      &lt;stroke
          android:width="0.33dp"
          android:color="#4D000000"
          /&gt;
      &lt;solid
          android:color="@color/colorWhite"/&gt;
  
  &lt;/shape&gt;
  </code></pre>