android - Hide Toolbar Up Button in certain page of WebViewClient -

i trying implement material design webviewclient. webviewclient opens index.html saved in asset. want achieve when home page, index.html opened, there shouldn't "up button". "up button" should shown when click on link in index.html. have tried

getsupportactionbar().setdisplayhomeasupenabled(true); 

but apparently, show "up button" of pages. how hide "up button" homepage, index.html?

problem solved adding under onpagefinished in webviewclient

public void onpagefinished(webview view, string url) {          if (url.equals("file:///android_asset/index.html")) {             getsupportactionbar().setdisplayhomeasupenabled(false);         } else {             getsupportactionbar().setdisplayhomeasupenabled(true);         }         super.onpagefinished(view, url);     }