Support for other protocols in Android webview

问题:

I've created a web view app, the page that is displayed features market:// links but upon clicking them I get the 404 screen along with the error that the protocol is not supported. I've tried looking through documentation but was unable to find anything relating to this. Any help is much appreciated.

回答1:

For me the JavaScript thing wasn't a solution as the HTML is not under my control. So if you need to control this from the application side, then there is a relative simple solution: Derive from WebViewClientand inject the implementation using WebView.setWebViewClient(). All you need to override in your WebViewClientimplementation is the shouldOverrideUrlLoading method as shown here:

public boolean shouldOverrideUrlLoading(WebView view, String url) {
    if (url != null && url.startsWith("market://")) {
        view.getContext().startActivity(
            new Intent(Intent.ACTION_VIEW, Uri.parse(url)));
        return true;
    } else {
        return false;
    }
}

For me this works fine.

回答2:

For the links to work you have to have the market app installed on your device/emulator. Also your app need to request a permission to access network.

UPD: as a workaround you can call java code from within the webview, for example if you generate links like this:

<a href="javascript:go('market://your.path.to.market.app')">..</a>

Define a javascript function named go():

<script type="text/javascript">
   function go(link) {
     if (handler) {
           handler.go(link);
         } else {
           document.location = link;
         }
   }
</script>

You then can pass in a handler object into the WebView:

webview.addJavascriptInterface(new Handler() {
        @Override
        public void go(String marketUrl) {
                         //start market intent here
        }
    },  "handler");

Handler interface can be defined as follows:

   public interface Handler{

    public void go(String url);

}

回答3:

HOPE THIS HELPS YOU

public boolean shouldOverrideUrlLoading(WebView view, String url) 
{
    if (url.startsWith("market://")||url.startsWith("vnd:youtube")||url.startsWith("tel:")||url.startsWith("mailto:"))
    {
        Intent intent = new Intent(Intent.ACTION_VIEW); 
        intent.setData(Uri.parse(url)); 
        startActivity(intent);
        return true;
     }
    else{
        view.loadUrl(url);
        return true;
        }
}

回答4:

Work for me:

webView = (WebView) findViewById(R.id.webView);
webView.setWebChromeClient(new WebChromeClient());
webView.getSettings().setPluginState(WebSettings.PluginState.ON);
webView.getSettings().setPluginState(WebSettings.PluginState.ON_DEMAND);

webView.setWebViewClient(new MyWebViewClient());
webView.getSettings().setJavaScriptEnabled(true);

webView.loadUrl("http://myweb.com");

private class MyWebViewClient extends WebViewClient {
    public boolean shouldOverrideUrlLoading(WebView view, String url) {
        if (url != null && url.startsWith("whatsapp://")) {
            view.getContext().startActivity(
                    new Intent(Intent.ACTION_VIEW, Uri.parse(url)));
            return true;
        } else {
            return false;
        }
    }
}

回答5:

It is important to understand how the webview and its clients (webviewclient and webchromeclient) works. Please go through the http://therockncoder.blogspot.in/2014/04/understanding-androids-webchromeclient.html

In the webviewclient's shouldOverrideUrlLoading() method, you can decide if you want to open the link in new browser or within the webview. If you don't override this method, it will by default open the link in a new browser outside of the your android application. If you want to open within webview, override the method as below

public boolean shouldOverrideUrlLoading(WebView view, String url) { <br>
    Log.v("activity", "INSIDE WEBVIEW CLIENT ON shouldOverrideUrlLoading");
        view.loadUrl(url);
        return false; //need to understand return value based on usage
    }

Schemes like whatsapp://send?text=Hello%20World! or market://details?id=xx.xx.xx will open the corresponding apps automatically if they are opened outside the webview and if that app is installed on the handset.

If you want to open certain links within webview and specific schemes outside webview, you need to override WebChromeClients onCreateWindow() method as explained in the link provided above. It should solve the purpose.

回答6:

Simplest solution

 Intent newApp = new Intent(Intent.ACTION_VIEW,  Uri.parse(URL));
startActivity(newApp);