我无法转到Webview的上一页，并且OnBackPressed（）在我的WebView活动中不起作用

Question

这是我的WebActivity代码。我有两个活动->资源活动和webActivity。我正在将URL从Resource Activity传递到WebActivity。请指导我应在哪个Activity中放置该代码，即Resource Activity或Web Activity？

public class WebActivity extends AppCompatActivity {


private WebView mwebview;
private ProgressDialog progressBar;

protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.webview);
    final WebView mwebview = (WebView) findViewById(R.id.webview);

    WebSettings webSettings = mwebview.getSettings();
    mwebview.setWebViewClient(new WebViewClient());
    webSettings.setJavaScriptEnabled(true);

    String uri = getIntent().getExtras().getString("uri");

    mwebview.loadUrl(uri);

    String auri = getIntent().getExtras().getString("auri");
    mwebview.loadUrl(auri);
    String huri = getIntent().getExtras().getString("huri");
    mwebview.loadUrl(huri);
    String eouri = getIntent().getExtras().getString("eouri");
    mwebview.loadUrl(eouri);
    String houri = getIntent().getExtras().getString("houri");
    mwebview.loadUrl(houri);
    String bouri = getIntent().getExtras().getString("bouri");
    mwebview.loadUrl(bouri);





    }
//My OnBackPressed Code 

@Override
 public void onBackPressed() 
 {
 if (mwebview.canGoBack())
  mwebview.goBack();
  else
  super.onBackPressed();

}




}