Android WebView err_unknown_url_scheme

Question

使用下面简单的代码我可以正确加载我的url，但是，当我尝试点击以mailto：whatsapp：和tg：（Telegram）开头的html链接时，我得到“ERR_UNKNOWN_URL_SCHEME”。

有人可以帮我解决这个问题吗？不幸的是我根本不懂Java :(

谢谢。

import android.app.Activity;
import android.os.Bundle;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends Activity {

    private WebView mWebView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mWebView = (WebView) findViewById(R.id.activity_main_webview);

        // Force links and redirects to open in the WebView instead of in a browser
        mWebView.setWebViewClient(new WebViewClient());

        // Enable Javascript
        WebSettings webSettings = mWebView.getSettings();
        webSettings.setJavaScriptEnabled(true);

        // Use remote resource
        mWebView.loadUrl("http://myexample.com");
    }
}

Answer 1

您必须在Webview中设置客户端并将其传递给intent

webView.setWebViewClient(new WebViewClient() {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            if( URLUtil.isNetworkUrl(url) ) {
                return false;
            }
            if (appInstalledOrNot(url)) {
                Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
                startActivity( intent );
            } else {
                // do something if app is not installed
            }
            return true;
        }

    });
}

您可以使用方法检查是否已安装应用程序

private boolean appInstalledOrNot(String uri) {
        PackageManager pm = getPackageManager();
        try {
            pm.getPackageInfo(uri, PackageManager.GET_ACTIVITIES);
            return true;
        } catch (PackageManager.NameNotFoundException e) {
        }

        return false;
    }

Answer 2

您需要覆盖WebViewClient的方法shouldOverrideUrlLoading，您可以在其中自行控制链接传输。

因为html links that starts with mailto: whatsapp: and tg: (Telegram).不是常见的url以“http：//”或“https：//”开头，所以WebView无法将其解析到正确的位置，我们应该使用intent来重定向url。

例如：

        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            if (url == null || url.startsWith("http://") || url.startsWith("https://")) return false;

            try {
                Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
                view.getContext().startActivity(intent);
                return true;
            } catch (Exception e) {
                Log.i(TAG, "shouldOverrideUrlLoading Exception:" + e);
                return true;
            }
        }

然后将WebViewClient设置为WebView，如下所示：

public class MainActivity extends Activity {

private WebView mWebView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    mWebView = (WebView) findViewById(R.id.activity_main_webview);

    // Force links and redirects to open in the WebView instead of in a browser
    mWebView.setWebViewClient(new WebViewClient() {

    @Override
    public boolean shouldOverrideUrlLoading(WebView view, String url) {
        if (url == null || url.startsWith("http://") || url.startsWith("https://")) return false;

        try {
            Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
            view.getContext().startActivity(intent);
            return true;
        } catch (Exception e) {
            Log.i(TAG, "shouldOverrideUrlLoading Exception:" + e);
            return true;
        }
    }
    });

    // Enable Javascript
    WebSettings webSettings = mWebView.getSettings();
    webSettings.setJavaScriptEnabled(true);

    // Use remote resource
    mWebView.loadUrl("http://myexample.com");
}}

Answer 3

实际上WebView没有如何使用url方案，如mailto，tg，sms，phone。您应该覆盖shouldOverrideUrlloading（）方法，并在找到这些类型的方案时执行webview需要执行的操作。

 @Override
        public boolean shouldOverrideUrlLoading(WebView view, String  url)
        {

            if( URLUtil.isNetworkUrl(url) )
            {
                return false;
            }
            try {
                Intent intent = new Intent(Intent.ACTION_VIEW);
                intent.setData(Uri.parse(url));
                startActivity(intent);

            }catch(ActivityNotFoundException e)
            {
                Log.e("AndroiRide",e.toString());
                Toast.makeText(MainActivity.this,"No activity found",Toast.LENGTH_LONG).show();
            }

            return true;
        }

在API级别24中不推荐使用shouldOverrideUrlLoading（WebView视图，String url）。

所以重写public boolean shouldOverrideUrlLoading（WebView视图，WebResourceRequest请求）

@RequiresApi(Build.VERSION_CODES.N)
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request)
        {
            String url=request.getUrl().toString();
            if( URLUtil.isNetworkUrl(url) )
            {
                return false;
            }
            try {
                Intent intent = new Intent(Intent.ACTION_VIEW);
                intent.setData(Uri.parse(url));
                startActivity(intent);

            }catch(ActivityNotFoundException e)
            {
                Log.e("AndroiRide",e.toString());
                Toast.makeText(MainActivity.this,"No activity found",Toast.LENGTH_LONG).show();
            }

            return true;
        }

如果您创建自己的方案，请自定义代码。 [ERR unknown URL Scheme in Android WebView - Kotlin & Java code]

Answer 4

mailto链接不会被加载到你的webview.you在shouldOverrideUrlLoading中检查它并用intent处理它。

    public boolean shouldOverrideUrlLoading(WebView view, String url) {
    if (url.startsWith("mailto:")) {

        Intent share = new Intent(Intent.ACTION_SEND);
        share.setType("text/plain");
        share.putExtra(Intent.EXTRA_TEXT, message);
        startActivity(Intent.createChooser(share, "Title of the dialog the system will open"));
        view.reload();
        return true;
    }
  }

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