How to fullscreen youtube video in WebView
<p>I use following code:</p>

<pre><code>@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_test_web_view_play_youtube);
    WebView w = (WebView) findViewById(R.id.w);
    w.setWebChromeClient(new WebChromeClient());
    w.setWebViewClient(new WebViewClient());
    w.getSettings().setJavaScriptEnabled(true);
    w.loadUrl("https://www.youtube.com/watch?v=gY-HZg1Uwpc");
}
</code></pre>

<p>i get following screenshot</p>

<p><a href="https://i.stack.imgur.com/5z4Ab.png" rel="noreferrer"><img src="https://i.stack.imgur.com/5z4Ab.png" alt="enter image description here"></a></p>

<p>In this screenshot, I could not see "fullScreen" button.</p>