webview cangoback in fragment

if (NetworkState.isOnline(Objects.requireNonNull(getContext()))) {
                tvError.setVisibility(View.GONE);
                WebSettings webSettings = webView.getSettings();
                webSettings.setJavaScriptEnabled(true);
                webView.loadUrl(Constants.WEB_URL);
                webView.setWebChromeClient(new WebChromeClient());
                webView.setWebViewClient(new WebViewClient() {
                    @Override
                    public boolean shouldOverrideUrlLoading(WebView view, String url) {
                        view.loadUrl(url);

                        return true;
                    }
                    @Override
                    public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
                        // TODO: handle error in some way
                    }
                    @Override
                    public void onPageFinished(WebView view, String url) {
                        super.onPageFinished(view, url);
                        if (webView.getProgress() == 100) {
                            loading.dismiss();
                        }
                    }
                });

                webView.canGoBack();
                webView.setOnKeyListener(new View.OnKeyListener() {
                    public boolean onKey(View v, int keyCode, KeyEvent event) {
                        if (keyCode == KeyEvent.KEYCODE_BACK
                                && event.getAction() == MotionEvent.ACTION_UP
                                && webView.canGoBack()) {
                            webView.goBack();
                            return true;
                        }
                        return false;
                    }
                });

            } else {
                webView.setVisibility(View.GONE);
            }