我一直在努力从WebView上传文件。我在谷歌上搜索并实施了所有建议的解决方案(例如这篇SO帖子),但没有一个可行。

我有一个HTML页面与以下代码上传文件。

<form method="POST" enctype="multipart/form-data">
  File to upload: <input type="file" name="uploadfile">&nbsp;&nbsp;
  <input type="submit" value="Press to Upload..."> to upload the file!
</form>

它在桌面浏览器如Firefox和内置浏览器中运行良好 的模拟器/ AVD,即,当我点击“浏览…”按钮渲染 元素,浏览器打开一个对话框 框,在那里我可以选择一个文件上传。

然而,在android 3.0模拟器/ AVD中,当我点击“选择” 文件”,什么都没有发生,没有文件对话框被打开!


当前回答

我发现我需要3个接口定义,以处理不同版本的android。

public void openFileChooser(ValueCallback < Uri > uploadMsg) {
  mUploadMessage = uploadMsg;
  Intent i = new Intent(Intent.ACTION_GET_CONTENT);
  i.addCategory(Intent.CATEGORY_OPENABLE);
  i.setType("image/*");
  FreeHealthTrack.this.startActivityForResult(Intent.createChooser(i, "Image Chooser"), FILECHOOSER_RESULTCODE);
}

public void openFileChooser(ValueCallback < Uri > uploadMsg, String acceptType) {
  openFileChooser(uploadMsg);
}

public void openFileChooser(ValueCallback < Uri > uploadMsg, String acceptType, String capture) {
  openFileChooser(uploadMsg);
}

其他回答

我发现有必要在Android 4.1中定义公共void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture)。然后我采用了米歇尔·奥利弗的解决方案。

我找到了一个适合我的解决方案!在proguard-android.txt文件中增加一条规则:

-keepclassmembers class * extends android.webkit.WebChromeClient {
     public void openFileChooser(...);
}

Webview -单个和多个文件选择

你需要两分钟来实现这段代码:

build.gradle

implementation 'com.github.angads25:filepicker:1.1.1'

java代码:

import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.util.Log;
import android.view.KeyEvent;
import android.view.View;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;
import android.widget.Toast;

import com.bivoiclient.utils.Constants;
import com.github.angads25.filepicker.controller.DialogSelectionListener;
import com.github.angads25.filepicker.model.DialogConfigs;
import com.github.angads25.filepicker.model.DialogProperties;
import com.github.angads25.filepicker.view.FilePickerDialog;

import java.io.File;

public class WebBrowserScreen extends Activity {

    private WebView webView;
    private ValueCallback<Uri[]> mUploadMessage;
    private FilePickerDialog dialog;
    private String LOG_TAG = "DREG";
    private Uri[] results;

    @SuppressLint("SetJavaScriptEnabled")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_complain);

        webView = findViewById(R.id.webview);
        WebSettings webSettings = webView.getSettings();
        webSettings.setAppCacheEnabled(true);
        webSettings.setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);
        webSettings.setJavaScriptEnabled(true);
        webSettings.setLoadWithOverviewMode(true);
        webSettings.setAllowFileAccess(true);
        webView.setWebViewClient(new PQClient());
        webView.setWebChromeClient(new PQChromeClient());
        if (Build.VERSION.SDK_INT >= 19) {
            webView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
        } else {
            webView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
        }

        webView.loadUrl(Constants.COMPLAIN_URL);

    }

    private void openFileSelectionDialog() {

        if (null != dialog && dialog.isShowing()) {
            dialog.dismiss();
        }

        //Create a DialogProperties object.
        final DialogProperties properties = new DialogProperties();

        //Instantiate FilePickerDialog with Context and DialogProperties.
        dialog = new FilePickerDialog(WebBrowserScreen.this, properties);
        dialog.setTitle("Select a File");
        dialog.setPositiveBtnName("Select");
        dialog.setNegativeBtnName("Cancel");
        properties.selection_mode = DialogConfigs.MULTI_MODE; // for multiple files
//        properties.selection_mode = DialogConfigs.SINGLE_MODE; // for single file
        properties.selection_type = DialogConfigs.FILE_SELECT;

        //Method handle selected files.
        dialog.setDialogSelectionListener(new DialogSelectionListener() {
            @Override
            public void onSelectedFilePaths(String[] files) {
                results = new Uri[files.length];
                for (int i = 0; i < files.length; i++) {
                    String filePath = new File(files[i]).getAbsolutePath();
                    if (!filePath.startsWith("file://")) {
                        filePath = "file://" + filePath;
                    }
                    results[i] = Uri.parse(filePath);
                    Log.d(LOG_TAG, "file path: " + filePath);
                    Log.d(LOG_TAG, "file uri: " + String.valueOf(results[i]));
                }
                mUploadMessage.onReceiveValue(results);
                mUploadMessage = null;
            }
        });
        dialog.setOnCancelListener(new DialogInterface.OnCancelListener() {
            @Override
            public void onCancel(DialogInterface dialogInterface) {
                if (null != mUploadMessage) {
                    if (null != results && results.length >= 1) {
                        mUploadMessage.onReceiveValue(results);
                    } else {
                        mUploadMessage.onReceiveValue(null);
                    }
                }
                mUploadMessage = null;
            }
        });
        dialog.setOnDismissListener(new DialogInterface.OnDismissListener() {
            @Override
            public void onDismiss(DialogInterface dialogInterface) {
                if (null != mUploadMessage) {
                    if (null != results && results.length >= 1) {
                        mUploadMessage.onReceiveValue(results);
                    } else {
                        mUploadMessage.onReceiveValue(null);
                    }
                }
                mUploadMessage = null;
            }
        });

        dialog.show();

    }

    public class PQChromeClient extends WebChromeClient {

        @Override
        public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathCallback, FileChooserParams fileChooserParams) {
            // Double check that we don't have any existing callbacks
            if (mUploadMessage != null) {
                mUploadMessage.onReceiveValue(null);
            }
            mUploadMessage = filePathCallback;

            openFileSelectionDialog();

            return true;
        }

    }

    //Add this method to show Dialog when the required permission has been granted to the app.
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String permissions[], @NonNull int[] grantResults) {
        switch (requestCode) {
            case FilePickerDialog.EXTERNAL_READ_PERMISSION_GRANT: {
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    if (dialog != null) {
                        openFileSelectionDialog();
                    }
                } else {
                    //Permission has not been granted. Notify the user.
                    Toast.makeText(WebBrowserScreen.this, "Permission is Required for getting list of files", Toast.LENGTH_SHORT).show();
                }
            }
        }
    }

    public boolean onKeyDown(int keyCode, KeyEvent event) {
        // Check if the key event was the Back button and if there's history
        if ((keyCode == KeyEvent.KEYCODE_BACK) && webView.canGoBack()) {
            webView.goBack();
            return true;
        }
        // If it wasn't the Back key or there's no web page history, bubble up to the default
        // system behavior (probably exit the activity)

        return super.onKeyDown(keyCode, event);
    }


    public class PQClient extends WebViewClient {
        ProgressBar progressDialog;

        public boolean shouldOverrideUrlLoading(WebView view, String url) {

            // If url contains mailto link then open Mail Intent
            if (url.contains("mailto:")) {

                // Could be cleverer and use a regex
                //Open links in new browser
                view.getContext().startActivity(
                        new Intent(Intent.ACTION_VIEW, Uri.parse(url)));

                // Here we can open new activity

                return true;

            } else {
                // Stay within this webview and load url
                view.loadUrl(url);
                return true;
            }
        }

        // Show loader on url load
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            // Then show progress  Dialog
            // in standard case YourActivity.this
            if (progressDialog == null) {
                progressDialog = findViewById(R.id.progressBar);
                progressDialog.setVisibility(View.VISIBLE);
            }
        }

        // Called when all page resources loaded
        public void onPageFinished(WebView view, String url) {
            webView.loadUrl("javascript:(function(){ " +
                    "document.getElementById('android-app').style.display='none';})()");

            try {
                // Close progressDialog
                progressDialog.setVisibility(View.GONE);
            } catch (Exception exception) {
                exception.printStackTrace();
            }
        }
    }

}

自定义WebChromeClient:

class AppChromeClient(private val fragmentWeakReference: WeakReference<WebViewFragment>) :
WebChromeClient() {
private var openFileCallback: ValueCallback<Array<Uri>>? = null

override fun onShowFileChooser(
    webView: WebView?,
    filePathCallback: ValueCallback<Array<Uri>>?,
    fileChooserParams: FileChooserParams?
): Boolean {
    if (filePathCallback == null) {
        return (super.onShowFileChooser(webView, filePathCallback, fileChooserParams))
    }
    openFileCallback = filePathCallback
    val webViewFragment = fragmentWeakReference.get() ?: return false
    webViewFragment.launchGetMultipleContents("*/*")

    return true
}

fun receiveFileCallback(result: Array<Uri>) {
    openFileCallback?.onReceiveValue(result)
    openFileCallback = null
}
}

WebViewFragment:

class WebViewFragment : Fragment() {
    private var _binding: FragmentWebviewBinding? = null
    private val binding get() = _binding!!
    private lateinit var webView: WebView
    private val chromeClient = AppChromeClient(WeakReference(this))
    private var contentLauncher: ActivityResultLauncher<String> = getMultipleContentLauncher()

    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View {
        _binding = FragmentWebviewBinding.inflate(inflater, container, false)

        webView.webChromeClient = chromeClient
        val url = requireContext().getString(R.string.app_domain)
        webView.setting.javaScriptEnabled = true
        webView.loadUrl(url)
        return binding.root
    }


    private fun getMultipleContentLauncher(): ActivityResultLauncher<String> {
        return this.registerForActivityResult(ActivityResultContracts.GetMultipleContents()) { list ->
            if (list.isEmpty()) {
                showToast("No files selected")
            }
            chromeClient.receiveFileCallback(list.toTypedArray())
        }
    }


    fun launchGetMultipleContents(type: String) {
        contentLauncher.launch(type)
    }
}

Hifarrer的完整解决方案对我很有帮助。

但是,我遇到了许多其他问题-支持其他mime类型,列出捕获设备(相机,视频,音频编码器),立即打开捕获设备(例如:<input accept="image/*;capture">)…

所以,我做了一个解决方案,与默认的web浏览器应用程序完全相同。

我使用的是android-4.4.3_r1/src/com/android/browser/UploadHandler.java。(感谢鲁珀特·罗恩斯利)

package org.mospi.agatenativewebview;

import java.io.File;
import java.lang.reflect.Method;
import java.net.URL;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.ActivityNotFoundException;
import android.content.DialogInterface;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.View;
import android.webkit.JsResult;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebSettings.PluginState;
import android.widget.Toast;

public class MainActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        WebView webView = (WebView) findViewById(R.id.webView1);

        initWebView(webView);
        webView.loadUrl("http://google.com"); // TODO input your url

    }

    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);
    }

    class MyWebChromeClient extends WebChromeClient {
        public MyWebChromeClient() {

        }

        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);
        }

        // Android 4.4, 4.4.1, 4.4.2
        // openFileChooser function is not called on Android 4.4, 4.4.1, 4.4.2,
        // you may use your own java script interface or other hybrid framework.          

        // Android 5.0.1
        public boolean onShowFileChooser(
                WebView webView, ValueCallback<Uri[]> filePathCallback,
                FileChooserParams fileChooserParams) {

            String acceptTypes[] = fileChooserParams.getAcceptTypes();

            String acceptType = "";
            for (int i = 0; i < acceptTypes.length; ++ i) {
                if (acceptTypes[i] != null && acceptTypes[i].length() != 0)
                    acceptType += acceptTypes[i] + ";";
            }
            if (acceptType.length() == 0)
                acceptType = "*/*";

            final ValueCallback<Uri[]> finalFilePathCallback = filePathCallback;

            ValueCallback<Uri> vc = new ValueCallback<Uri>() {

                @Override
                public void onReceiveValue(Uri value) {

                    Uri[] result;
                    if (value != null)
                        result = new Uri[]{value};
                    else
                        result = null;

                    finalFilePathCallback.onReceiveValue(result);

                }
            };

            openFileChooser(vc, acceptType, "filesystem");


            return true;
       }
    };

    class Controller {
        final static int FILE_SELECTED = 4;

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

    // copied from android-4.4.3_r1/src/com/android/browser/UploadHandler.java
    //////////////////////////////////////////////////////////////////////

    /*
     * Copyright (C) 2010 The Android Open Source Project
     *
     * Licensed under the Apache License, Version 2.0 (the "License");
     * you may not use this file except in compliance with the License.
     * You may obtain a copy of the License at
     *
     *      http://www.apache.org/licenses/LICENSE-2.0
     *
     * Unless required by applicable law or agreed to in writing, software
     * distributed under the License is distributed on an "AS IS" BASIS,
     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     * See the License for the specific language governing permissions and
     * limitations under the License.
     */

    // package com.android.browser;
    //
    // import android.app.Activity;
    // import android.content.ActivityNotFoundException;
    // import android.content.Intent;
    // import android.net.Uri;
    // import android.os.Environment;
    // import android.provider.MediaStore;
    // import android.webkit.ValueCallback;
    // import android.widget.Toast;
    //
    // import java.io.File;
    // import java.util.Vector;
    //
    // /**
    // * Handle the file upload callbacks from WebView here
    // */
    // public class UploadHandler {

    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);
        }
    }
}

res/values/string.xml的额外字符串资源:

<string name="uploads_disabled">File uploads are disabled.</string>
<string name="choose_upload">Choose file for upload</string>

如果你正在使用proguard,你可能需要proguard-project.txt中的以下选项:

-keepclassmembers class * extends android.webkit.WebChromeClient {
   public void openFileChooser(...);
}

更新#1 (2015.09.09)

增加了Android 5.0.1兼容性的代码。