当 webview 中无法访问互联网时，如何在 android 中显示消息并隐藏 url？

Question

当网络视图中无法访问互联网时，如何在 Android 应用程序中显示消息并隐藏 URL？如果互联网连接不可用，我不想显示 URL 和进度条。

这是我的代码。请向我提供正确的代码。我是安卓初学者。

public class WebViewClientDemoActivity extends Activity {
    /** Called when the activity is first created. */

    WebView web;
    ProgressBar progressBar;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        web = (WebView) findViewById(R.id.webview01);
        progressBar = (ProgressBar) findViewById(R.id.progressBar1);

        web.setWebViewClient(new myWebClient());
        web.getSettings().setJavaScriptEnabled(true);
        web.loadUrl("http://www.vijaytutorials.com/mo");
    }

    public class myWebClient extends WebViewClient
    {
        @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            // TODO Auto-generated method stub
            super.onPageStarted(view, url, favicon);
        }

        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            // TODO Auto-generated method stub

            view.loadUrl(url);
            return true;

        }

        @Override
        public void onPageFinished(WebView view, String url) {
            // TODO Auto-generated method stub
            super.onPageFinished(view, url);

            progressBar.setVisibility(View.GONE);
        }
    }

    // To handle "Back" key press event for WebView to go back to previous screen.
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) 
    {
        if ((keyCode == KeyEvent.KEYCODE_BACK) && web.canGoBack()) {
            web.goBack();
            return true;
        }
        return super.onKeyDown(keyCode, event);
    }
}

Answer 1

您可以覆盖 WebView 的错误处理程序，并显示 Toast 或显示您创建的图像，告诉用户存在网络错误：

@Override
public void onReceivedError(WebView view, int errorCode, String description, String url)
{
    view.loadUrl("file:///[your error image or page goes here]");
}