安卓 WebView : Mailto Unable to Implement

Question

我无法在下面给出的自定义 webview 中实现 mailto 链接功能。请帮我混合这两个代码我对 android 比较陌生。我不知道如何实现 mailto 代码。

stackoverflow上的解决方案:

Mailto 代码

   @Override
    public boolean shouldOverrideUrlLoading(WebView view, String url) {     
        if(url.startsWith("mailto:")){
            MailTo mt = MailTo.parse(url);
            Intent i = new Intent(Intent.ACTION_SEND);
            i.setType("text/plain");
            i.putExtra(Intent.EXTRA_EMAIL, new String[]{mt.getTo()});
            i.putExtra(Intent.EXTRA_SUBJECT, mt.getSubject());
            i.putExtra(Intent.EXTRA_CC, mt.getCc());
            i.putExtra(Intent.EXTRA_TEXT, mt.getBody());
            mContext.startActivity(i);
            view.reload();
            return true;
        }
        view.loadUrl(url);
        return true;
    }

我的代码

 public class MainActivity extends Activity  implements OnClickListener {

  final Context context = this;
private WebView webView;
 private ImageButton btnrefresh;    
 private TextView txtrefresh;
 private Menu optionsMenu;



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


    //define button 
    btnrefresh = (ImageButton) findViewById(R.id.imageButton1);

    btnrefresh.setOnClickListener(this);
    btnrefresh.setVisibility(View.GONE);

    //define textView
    txtrefresh = (TextView)findViewById((R.id.textView1));
    txtrefresh.setVisibility(View.GONE);


    if(isConnected())
    {

        webView = (WebView) findViewById(R.id.webView1);
        webView.getSettings().setJavaScriptEnabled(true);       
    //  webView.getSettings().setPluginState(PluginState.ON);
      webView.setWebViewClient(new WebViewClient());
        initWebView(webView);                         
        webView.loadUrl("xxxxx");               

        }


    else
    {

    RelativeLayout rel = (RelativeLayout)findViewById(R.id.relativelayout1);
    rel.setOnClickListener(new View.OnClickListener(){
       @Override
       public void onClick(View v){
         refresh();
       }
   });
        btnrefresh.setVisibility(View.VISIBLE); 
        txtrefresh.setVisibility(View.VISIBLE);
        Toast.makeText(getBaseContext(), "No Internet Connection !!", Toast.LENGTH_SHORT).show();


    }       
}

public boolean onCreateOptionsMenu(Menu menu) {
    this.optionsMenu = menu;
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main_activity_actions, menu);
    return super.onCreateOptionsMenu(menu);
}

public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
    case R.id.airport_menuRefresh:
        webView.reload();
        Toast.makeText(getBaseContext(), "Refeshing...", Toast.LENGTH_SHORT).show();
        // Complete with your code
    return true;

     case R.id.goBack:
    if(webView.canGoBack()) {
        webView.goBack();
    }
    return true;

    case R.id.goForward:
    if(webView.canGoForward()) {
        webView.goForward();
    }
    return true;
    default:
    return super.onOptionsItemSelected(item);
    }
}



public void refresh()
{
    if (isConnected()) {
    btnrefresh.setVisibility(View.GONE);
    txtrefresh.setVisibility(View.GONE);
    webView = (WebView) findViewById(R.id.webView1);
    webView.getSettings().setJavaScriptEnabled(true);
    webView.setWebViewClient(new WebViewClient());
        initWebView(webView);       
    webView.loadUrl("xxxxxx");          


    Toast.makeText(getBaseContext(), "Connected !!", Toast.LENGTH_LONG).show();

    Toast.makeText(getBaseContext(), "Loading....", Toast.LENGTH_SHORT).show();
    Toast.makeText(getBaseContext(), "Please wait....", Toast.LENGTH_SHORT).show();
    }
    else
    {
        Toast.makeText(getBaseContext(), "No Internet Connection !!", Toast.LENGTH_SHORT).show();
    }       
}



 public boolean isConnected(){
        ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Activity.CONNECTIVITY_SERVICE);
            NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
            if (networkInfo != null && networkInfo.isConnected())
            {
           return true;
            }
            else                    
                return false;    
    }


    public void wifi()
    {
        WifiManager wifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
        wifi.setWifiEnabled(true);
    }

    public void alertwifi()
    {
    AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(context);

        // set title
        alertDialogBuilder.setTitle("NO Internet Connection!!");

        // set dialog message
        alertDialogBuilder
            .setMessage("Click below to turn on Wifi or Enable Data pack")
            .setCancelable(false)
            .setPositiveButton("Wifi",new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog,int id) {
                    // if this button is clicked, close
                    // current activity
                    wifi();
                }
              })
               .setNeutralButton("GPRS",new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog,int id) {
                    // if this button is clicked, close
                    // current activity
                    datapack();
                }
              })
            .setNegativeButton("Back",new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog,int id) {
                    // if this button is clicked, just close
                    // the dialog box and do nothing

                    dialog.cancel();


                }
            });


            // create alert dialog
            AlertDialog alertDialog = alertDialogBuilder.create();

            // show it
            alertDialog.show();
        }

    public void datapack()
    {
        try
        {
    ConnectivityManager dataManager;
    dataManager  = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
    Method dataMtd = ConnectivityManager.class.getDeclaredMethod("setMobileDataEnabled", boolean.class);
    dataMtd.setAccessible(true);
    dataMtd.invoke(dataManager, true);
        }
        catch(Exception e)
        {
            e.printStackTrace();

        }
    }

    @Override
       public boolean onKeyDown(int keyCode, KeyEvent event) {
           if ((keyCode == KeyEvent.KEYCODE_BACK)) {
               AlertDialog.Builder alertbox = new AlertDialog.Builder(MainActivity.this);

               alertbox.setTitle("Do You Want To Exit ?");
               alertbox.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                   public void onClick(DialogInterface arg0, int arg1) { 
                      // finish used for destroyed activity
                       exit();
                   }
               });

               alertbox.setNegativeButton("No", new DialogInterface.OnClickListener() {
                   public void onClick(DialogInterface arg0, int arg1) {
                           // Nothing will be happened when clicked on no button 
                           // of Dialog     
                 }
               });

               alertbox.show();
           }
           return super.onKeyDown(keyCode, event);
       }
    public void exit()
    {
         Intent intent = new Intent(Intent.ACTION_MAIN);
         intent.addCategory(Intent.CATEGORY_HOME);
         intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
         startActivity(intent);
    }


        public void onClick(View v) 

      {


        //refresh ImageButton function

            if (v == btnrefresh) 
            {
                refresh();
            }


            }

        private final static Object methodInvoke(Object obj, String method, Class<?>[] parameterTypes, Object[] args) {
            try {
                Method m = obj.getClass().getMethod(method, new Class[] { boolean.class });
                m.invoke(obj, args);
            } catch (Exception e) {
                e.printStackTrace();
            }

            return null;
        }


        private void initWebView(WebView webView) {

            WebSettings settings = webView.getSettings();

            settings.setJavaScriptEnabled(true);
            settings.setAllowFileAccess(true);
            settings.setDomStorageEnabled(true);
            settings.setCacheMode(WebSettings.LOAD_NO_CACHE);
            settings.setLoadWithOverviewMode(true);
            settings.setUseWideViewPort(true);
            settings.setSupportZoom(true);
            // settings.setPluginsEnabled(true);
            methodInvoke(settings, "setPluginsEnabled", new Class[] { boolean.class }, new Object[] { true });
            // settings.setPluginState(PluginState.ON);
            methodInvoke(settings, "setPluginState", new Class[] { PluginState.class }, new Object[] { PluginState.ON });
            // settings.setPluginsEnabled(true);
            methodInvoke(settings, "setPluginsEnabled", new Class[] { boolean.class }, new Object[] { true });
            // settings.setAllowUniversalAccessFromFileURLs(true);
            methodInvoke(settings, "setAllowUniversalAccessFromFileURLs", new Class[] { boolean.class }, new Object[] { true });
            // settings.setAllowFileAccessFromFileURLs(true);
            methodInvoke(settings, "setAllowFileAccessFromFileURLs", new Class[] { boolean.class }, new Object[] { true });

            webView.setScrollBarStyle(View.SCROLLBARS_INSIDE_OVERLAY);
            webView.clearHistory();
            webView.clearFormData();
            webView.clearCache(true);

            webView.setWebChromeClient(new MyWebChromeClient());
            // webView.setDownloadListener(downloadListener);


        }



        UploadHandler mUploadHandler;

        @Override
        protected void onActivityResult(int requestCode, int resultCode, Intent intent) {

            if (requestCode == Controller.FILE_SELECTED) {
                // Chose a file from the file picker.
                if (mUploadHandler != null) {
                    mUploadHandler.onResult(resultCode, intent);
                }
            }

            super.onActivityResult(requestCode, resultCode, intent);
        }

        @SuppressLint("NewApi")
        class MyWebChromeClient extends WebChromeClient {
            public MyWebChromeClient() {

            }


            @SuppressLint("NewApi")
            private String getTitleFromUrl(String url) {
                String title = url;
                try {
                    URL urlObj = new URL(url);
                    String host = urlObj.getHost();
                    if (host != null && !host.isEmpty()) {
                        return urlObj.getProtocol() + "://" + host;
                    }
                    if (url.startsWith("file:")) {
                        String fileName = urlObj.getFile();
                        if (fileName != null && !fileName.isEmpty()) {
                            return fileName;
                        }
                    }
                } catch (Exception e) {
                    // ignore
                }

                return title;
            }

            @Override
            public boolean onJsAlert(WebView view, String url, String message, final JsResult result) {
                String newTitle = getTitleFromUrl(url);

                new AlertDialog.Builder(MainActivity.this).setTitle(newTitle).setMessage(message).setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {

                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        result.confirm();
                    }
                }).setCancelable(false).create().show();
                return true;
                // return super.onJsAlert(view, url, message, result);
            }

            @Override
            public boolean onJsConfirm(WebView view, String url, String message, final JsResult result) {

                String newTitle = getTitleFromUrl(url);

                new AlertDialog.Builder(MainActivity.this).setTitle(newTitle).setMessage(message).setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {

                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        result.confirm();
                    }
                }).setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        result.cancel();
                    }
                }).setCancelable(false).create().show();
                return true;

                // return super.onJsConfirm(view, url, message, result);
            }

            // Android 2.x
            public void openFileChooser(ValueCallback<Uri> uploadMsg) {
                openFileChooser(uploadMsg, "");
            }

            // Android 3.0
            public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType) {
                openFileChooser(uploadMsg, "", "filesystem");
            }

            // Android 4.1
            public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) {
                mUploadHandler = new UploadHandler(new Controller());
                mUploadHandler.openFileChooser(uploadMsg, acceptType, capture);
            }
        };

        class Controller {
            final static int FILE_SELECTED = 4;

            Activity getActivity() {
                return MainActivity.this;
            }
        }


        class UploadHandler {
            /*
             * The Object used to inform the WebView of the file to upload.
             */
            private ValueCallback<Uri> mUploadMessage;
            private String mCameraFilePath;
            private boolean mHandled;
            private boolean mCaughtActivityNotFoundException;
            private Controller mController;
            public UploadHandler(Controller controller) {
                mController = controller;
            }
            String getFilePath() {
                return mCameraFilePath;
            }
            boolean handled() {
                return mHandled;
            }
            void onResult(int resultCode, Intent intent) {
                if (resultCode == Activity.RESULT_CANCELED && mCaughtActivityNotFoundException) {
                    // Couldn't resolve an activity, we are going to try again so skip
                    // this result.
                    mCaughtActivityNotFoundException = false;
                    return;
                }
                Uri result = intent == null || resultCode != Activity.RESULT_OK ? null
                        : intent.getData();
                // As we ask the camera to save the result of the user taking
                // a picture, the camera application does not return anything other
                // than RESULT_OK. So we need to check whether the file we expected
                // was written to disk in the in the case that we
                // did not get an intent returned but did get a RESULT_OK. If it was,
                // we assume that this result has came back from the camera.
                if (result == null && intent == null && resultCode == Activity.RESULT_OK) {
                    File cameraFile = new File(mCameraFilePath);
                    if (cameraFile.exists()) {
                        result = Uri.fromFile(cameraFile);
                        // Broadcast to the media scanner that we have a new photo
                        // so it will be added into the gallery for the user.
                        mController.getActivity().sendBroadcast(
                                new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, result));
                    }
                }
                mUploadMessage.onReceiveValue(result);
                mHandled = true;
                mCaughtActivityNotFoundException = false;
            }
            void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) {
                final String imageMimeType = "image/*";
                final String videoMimeType = "video/*";
                final String audioMimeType = "audio/*";
                final String mediaSourceKey = "capture";
                final String mediaSourceValueCamera = "camera";
                final String mediaSourceValueFileSystem = "filesystem";
                final String mediaSourceValueCamcorder = "camcorder";
                final String mediaSourceValueMicrophone = "microphone";
                // According to the spec, media source can be 'filesystem' or 'camera' or 'camcorder'
                // or 'microphone' and the default value should be 'filesystem'.
                String mediaSource = mediaSourceValueFileSystem;
                if (mUploadMessage != null) {
                    // Already a file picker operation in progress.
                    return;
                }
                mUploadMessage = uploadMsg;
                // Parse the accept type.
                String params[] = acceptType.split(";");
                String mimeType = params[0];
                if (capture.length() > 0) {
                    mediaSource = capture;
                }
                if (capture.equals(mediaSourceValueFileSystem)) {
                    // To maintain backwards compatibility with the previous implementation
                    // of the media capture API, if the value of the 'capture' attribute is
                    // "filesystem", we should examine the accept-type for a MIME type that
                    // may specify a different capture value.
                    for (String p : params) {
                        String[] keyValue = p.split("=");
                        if (keyValue.length == 2) {
                            // Process key=value parameters.
                            if (mediaSourceKey.equals(keyValue[0])) {
                                mediaSource = keyValue[1];
                            }
                        }
                    }
                }
                //Ensure it is not still set from a previous upload.
                mCameraFilePath = null;
                if (mimeType.equals(imageMimeType)) {
                    if (mediaSource.equals(mediaSourceValueCamera)) {
                        // Specified 'image/*' and requested the camera, so go ahead and launch the
                        // camera directly.
                        startActivity(createCameraIntent());
                        return;
                    } else {
                        // Specified just 'image/*', capture=filesystem, or an invalid capture parameter.
                        // In all these cases we show a traditional picker filetered on accept type
                        // so launch an intent for both the Camera and image/* OPENABLE.
                        Intent chooser = createChooserIntent(createCameraIntent());
                        chooser.putExtra(Intent.EXTRA_INTENT, createOpenableIntent(imageMimeType));
                        startActivity(chooser);
                        return;
                    }
                } else if (mimeType.equals(videoMimeType)) {
                    if (mediaSource.equals(mediaSourceValueCamcorder)) {
                        // Specified 'video/*' and requested the camcorder, so go ahead and launch the
                        // camcorder directly.
                        startActivity(createCamcorderIntent());
                        return;
                   } else {
                        // Specified just 'video/*', capture=filesystem or an invalid capture parameter.
                        // In all these cases we show an intent for the traditional file picker, filtered
                        // on accept type so launch an intent for both camcorder and video/* OPENABLE.
                        Intent chooser = createChooserIntent(createCamcorderIntent());
                        chooser.putExtra(Intent.EXTRA_INTENT, createOpenableIntent(videoMimeType));
                        startActivity(chooser);
                        return;
                    }
                } else if (mimeType.equals(audioMimeType)) {
                    if (mediaSource.equals(mediaSourceValueMicrophone)) {
                        // Specified 'audio/*' and requested microphone, so go ahead and launch the sound
                        // recorder.
                        startActivity(createSoundRecorderIntent());
                        return;
                    } else {
                        // Specified just 'audio/*',  capture=filesystem of an invalid capture parameter.
                        // In all these cases so go ahead and launch an intent for both the sound
                        // recorder and audio/* OPENABLE.
                        Intent chooser = createChooserIntent(createSoundRecorderIntent());
                        chooser.putExtra(Intent.EXTRA_INTENT, createOpenableIntent(audioMimeType));
                        startActivity(chooser);
                        return;
                    }
                }
                // No special handling based on the accept type was necessary, so trigger the default
                // file upload chooser.
                startActivity(createDefaultOpenableIntent());
            }
            private void startActivity(Intent intent) {
                try {
                    mController.getActivity().startActivityForResult(intent, Controller.FILE_SELECTED);
                } catch (ActivityNotFoundException e) {
                    // No installed app was able to handle the intent that
                    // we sent, so fallback to the default file upload control.
                    try {
                        mCaughtActivityNotFoundException = true;
                        mController.getActivity().startActivityForResult(createDefaultOpenableIntent(),
                                Controller.FILE_SELECTED);
                    } catch (ActivityNotFoundException e2) {
                        // Nothing can return us a file, so file upload is effectively disabled.
                        Toast.makeText(mController.getActivity(), R.string.uploads_disabled,
                                Toast.LENGTH_LONG).show();
                    }
                }
            }
            private Intent createDefaultOpenableIntent() {
                // Create and return a chooser with the default OPENABLE
                // actions including the camera, camcorder and sound
                // recorder where available.
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType("*/*");
                Intent chooser = createChooserIntent(createCameraIntent(), createCamcorderIntent(),
                        createSoundRecorderIntent());
                chooser.putExtra(Intent.EXTRA_INTENT, i);
                return chooser;
            }
            private Intent createChooserIntent(Intent... intents) {
                Intent chooser = new Intent(Intent.ACTION_CHOOSER);
                chooser.putExtra(Intent.EXTRA_INITIAL_INTENTS, intents);
                chooser.putExtra(Intent.EXTRA_TITLE,
                        mController.getActivity().getResources()
                                .getString(R.string.choose_upload));
                return chooser;
            }
            private Intent createOpenableIntent(String type) {
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType(type);
                return i;
            }
            private Intent createCameraIntent() {
                Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                File externalDataDir = Environment.getExternalStoragePublicDirectory(
                        Environment.DIRECTORY_DCIM);
                File cameraDataDir = new File(externalDataDir.getAbsolutePath() +
                        File.separator + "browser-photos");
                cameraDataDir.mkdirs();
                mCameraFilePath = cameraDataDir.getAbsolutePath() + File.separator +
                        System.currentTimeMillis() + ".jpg";
                cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(new File(mCameraFilePath)));
                return cameraIntent;
            }
            private Intent createCamcorderIntent() {
                return new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
            }
            private Intent createSoundRecorderIntent() {
                return new Intent(MediaStore.Audio.Media.RECORD_SOUND_ACTION);
            }
        }
    }









enter code here

Answer 1

我认为 webView.setWebViewClient(new WebViewClient()); 这应该是这样的:

webView.setWebViewClient(new WebViewClient() {

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

                if (url.startsWith("tel:")) {
                    initiateCall(url);
                    return true;
                }
                if (url.startsWith("mailto:")) {
                    sendEmail(url.substring(7));
                    return true;
                }

                return false;
            }

发送邮件将是:

private void sendEmail(String add) {
         Intent i = new Intent(Intent.ACTION_SEND);
         i.setType("text/plain");
         i.putExtra(Intent.EXTRA_EMAIL, new String[] { add });
          try {
         startActivity(Intent.createChooser(i, "Send mail..."));
         } catch (android.content.ActivityNotFoundException ex) {
         Toast.makeText(WebViewActivity.this,
         "There are no email clients installed.", Toast.LENGTH_SHORT)
         .show();
         }

        }