private WebView mWebView;

@SuppressLint("SetJavaScriptEnabled")
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if(android.os.Build.VERSION.SDK_INT >=11)
    {
        getWindow().addFlags(16777216);
    }
    setContentView(R.layout.activity_main);

    mWebView = (WebView) findViewById (R.id.webview);
    mWebView.getSettings().setJavaScriptEnabled(true);
    mWebView.loadUrl("http://myUrl");
    mWebView.setWebViewClient(new HelloWebViewClient());
    mWebView.getSettings().setSupportMultipleWindows(true);
    mWebView.setWebChromeClient(new ChromeClient());
    mWebView.setWebViewClient(new WebClient1()
    {
         @SuppressLint("NewApi")
        @ Override public boolean shouldOverrideUrlLoading(WebView view, String url) {
            if (url.startsWith("vnd.youtube")){
                startActionMode((Callback) new Intent(Intent.ACTION_VIEW, Uri.parse(url)));
                return true;
             } else{
                return false;
             }
         }
     }
    );
}




    private class HelloWebViewClient extends WebViewClient {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            view.loadUrl(url);
            return true;
        }
    }

    private class  ChromeClient extends WebChromeClient {
        FrameLayout.LayoutParams LayoutParameters = new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,
                FrameLayout.LayoutParams.MATCH_PARENT);
        private Object mCustomView;
        private RelativeLayout mContentView;
        private FrameLayout mCustomViewContainer;
        private CustomViewCallback mCustomViewCallback;

        @Override
        public void onShowCustomView(View view, CustomViewCallback callback) {
            // if a view already exists then immediately terminate the new one
            if (mCustomView != null) {
                callback.onCustomViewHidden();
                return;
            }

            mContentView.setVisibility(View.GONE);
            mCustomViewContainer = new FrameLayout(MainActivity.this);
            mCustomViewContainer.setLayoutParams(LayoutParameters);
            mCustomViewContainer.setBackgroundResource(android.R.color.black);
            view.setLayoutParams(LayoutParameters);
            mCustomViewContainer.addView(view);
            mCustomView = view;
            mCustomViewCallback = callback;
            mCustomViewContainer.setVisibility(View.VISIBLE);
            setContentView(mCustomViewContainer);
        }

        @Override
        public void onHideCustomView() {
            if (mCustomView == null) {
                return;
            } else {
                // Hide the custom view.
                ((View) mCustomView).setVisibility(View.GONE);
                // Remove the custom view from its container.
                mCustomViewContainer.removeView((View) mCustomView);
                mCustomView = null;
                mCustomViewContainer.setVisibility(View.GONE);
                mCustomViewCallback.onCustomViewHidden();
                // Show the content view.
                mContentView.setVisibility(View.VISIBLE);
                setContentView(mContentView);
            }
        }
    }