title: Not able to set ShadowColor in react-native android
body: <h1>Environment</h1>
  <ul>
  <li><p>Environment:</p>
  <ul>
  <li>OS: macOS High Sierra 10.13.1</li>
  <li>Node: 8.9.1</li>
  <li>Yarn: 0.17.10</li>
  <li>npm: 5.6.0</li>
  <li>Watchman: 4.7.0</li>
  <li>Xcode: Xcode 9.2 Build version 9C40b</li>
  <li>Android Studio: 2.3 AI-162.4069837</li>
  </ul>
  </li>
  <li><p>Packages: (installed)</p>
  <ul>
  <li>react: 16.0.0</li>
  <li>react-native: 0.51.0</li>
  </ul>
  </li>
  </ul>
  <h1>Steps to Reproduce</h1>
  <h3>Run this code</h3>
  <pre><code>import React, {Component} from 'react';
  import {View, Text, TouchableOpacity} from 'react-native';
  class App extends Component {
    render() {
      return (&lt;View style={styles.container}&gt;
        &lt;View&gt;
          &lt;TouchableOpacity style={[styles.boxShadow, shadow]}&gt;
            &lt;Text style={styles.text}&gt;LOGIN&lt;/Text&gt;
          &lt;/TouchableOpacity&gt;
        &lt;/View&gt;
      &lt;/View&gt;);
    }
  }
  const shadow = {
    shadowColor: '#30C1DD',
    shadowRadius: 10,
    shadowOpacity: 0.6,
    elevation: 8,
    shadowOffset: {
      width: 0,
      height: 4
    }
  }
  const styles = {
    container: {
      flex: 1,
      justifyContent: 'center',
      alignItems: 'center'
    },
    boxShadow: {
      width: 200,
      height: 50,
      borderRadius: 10,
      backgroundColor: '#ed7171',
      justifyContent: 'center',
      alignItems: 'center'
    },
    text: {
      color: '#ffffff'
    }
  };
  export default App;
  </code></pre>
  <h1>Expected Behavior</h1>
  <p>Is there way to achieve like this Shadow in Android</p>
  <p><img src="https://user-images.githubusercontent.com/7195877/34039666-6d6a926e-e1b6-11e7-9581-96c55c6fb44d.png" alt="buttonshadow" /></p>
  <p>as shadow Props of react-native only supports in iOS</p>
  <ul>
  <li><strong>color need to be changed</strong></li>
  <li>Tried <code>elevation</code> but can not change default <strong>greyed</strong> color</li>
  <li>able to achieve in ios with <code>shadowColor</code> props but not in android as it is only support iOS</li>
  </ul>
  <h1>Actual Behavior</h1>
  <p>See sample code and preview.</p>
  <ul>
  <li>It should be work for android too.</li>
  <li>Shadow color is always grey, however I tried to change..</li>
  </ul>
  <h1>Reproducible Demo</h1>
  <p>This is sample snapshot in which I can only get shadow with elevation with only grey color [default].</p>
  <p><img src="https://user-images.githubusercontent.com/7195877/34040282-0129ae70-e1b9-11e7-8023-52944163410d.png" alt="screen shot 2017-12-15 at 4 56 54 pm" /></p>