title: Why is EditText repeating text when entering a not allowed char defined by "android:digits" attribute?
body: <p>My <code>Activity</code> has an <code>EditText</code> as defined bellow:</p>
  
  <pre><code>&lt;EditText 
      android:id="@android:id/text1"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:inputType="text"
      android:digits="0123456789.:"
      /&gt;
  </code></pre>
  
  <p>The allowed input should be <code>.</code>, <code>:</code> and <code>numbers</code>. But if a not allowed char is typed when the <code>EditText</code> is empty the text starts to be duplicated.</p>
  
  <p>For example, assuming the <code>EditText</code> is empty, type the following sequence: <code>abc123</code>.</p>
  
  <p>On my device the result is <code>1112123</code>, but the expected result should be just <code>123</code>.</p>
  
  <p>As this should be as simple as possible, I would not like to use an <code>InputFilter</code>.</p>