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

Android 8的Kotlin解决方案:

private var mUploadMessage: ValueCallback<Uri>? = null
private var uploadMessage: ValueCallback<Array<Uri>>? = null

常量:

const val FILECHOOSER_RESULTCODE = 1
const val REQUEST_SELECT_FILE = 100

WebView设置:

webView.webChromeClient = object : WebChromeClient() {
        override fun onPermissionRequest(request: PermissionRequest?) {
            Log.d("MainActivity", "onPermissionRequest")
            requestPermission(request)
        }


        // For Android 3.0+
        fun openFileChooser(uploadMsg: ValueCallback<*>, acceptType: String) {
            mUploadMessage = uploadMsg as ValueCallback<Uri>
            val i = Intent(Intent.ACTION_GET_CONTENT)
            i.addCategory(Intent.CATEGORY_OPENABLE)
            i.type = "*/*"
            this@MainActivity.startActivityForResult(
                    Intent.createChooser(i, "File Browser"),
                    FILECHOOSER_RESULTCODE)
        }

        //For Android 4.1
        fun openFileChooser(uploadMsg: ValueCallback<Uri>, acceptType: String, capture: String) {
            mUploadMessage = uploadMsg
            val i = Intent(Intent.ACTION_GET_CONTENT)
            i.addCategory(Intent.CATEGORY_OPENABLE)
            i.type = "image/*"
            this@MainActivity.startActivityForResult(Intent.createChooser(i, "File Chooser"), FILECHOOSER_RESULTCODE)

        }

        protected fun openFileChooser(uploadMsg: ValueCallback<Uri>) {
            mUploadMessage = uploadMsg
            val intent = Intent(Intent.ACTION_GET_CONTENT)
            intent.addCategory(Intent.CATEGORY_OPENABLE)
            intent.type = "*/*"
            startActivityForResult(Intent.createChooser(intent, "File Chooser"), FILECHOOSER_RESULTCODE)
        }

        override fun onShowFileChooser(webView: WebView?, filePathCallback: ValueCallback<Array<Uri>>?, fileChooserParams: FileChooserParams?): Boolean {
            uploadMessage?.onReceiveValue(null)
            uploadMessage = null

            uploadMessage = filePathCallback

            val intent = fileChooserParams!!.createIntent()
            try {
                startActivityForResult(intent, REQUEST_SELECT_FILE)
            } catch (e: ActivityNotFoundException) {
                uploadMessage = null
                Toast.makeText(applicationContext, "Cannot Open File Chooser", Toast.LENGTH_LONG).show()
                return false
            }

            return true
        }

    }

onactivityresult部分:

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        if (requestCode === REQUEST_SELECT_FILE) {
            if (uploadMessage == null)
                return
            print("result code = " + resultCode)
            var results: Array<Uri>? = WebChromeClient.FileChooserParams.parseResult(resultCode, data)
            uploadMessage?.onReceiveValue(results)
            uploadMessage = null
        }
    } else if (requestCode === FILECHOOSER_RESULTCODE) {
        if (null == mUploadMessage)
            return
        // Use MainActivity.RESULT_OK if you're implementing WebView inside Fragment
        // Use RESULT_OK only if you're implementing WebView inside an Activity
        val result = if (intent == null || resultCode !== RESULT_OK) null else intent.data
        mUploadMessage?.onReceiveValue(result)
        mUploadMessage = null
    } else
        Toast.makeText(applicationContext, "Failed to Upload Image", Toast.LENGTH_LONG).show()
}

请注意,我们的意图变量称为“数据”。

其他回答

我花了将近一个月的时间研究这个问题。一切都失败了。在多个网站中看到的所有代码都不工作。但这里存在最好的解决方案

https://github.com/chiclaim/android-webview-upload-file

步骤

1)点击克隆或下载

2)在本地目录中获取zip fle

3)解压压缩文件

4)开放Android工作室

5)转到文件---->打开>导航到你解压内容的目录。

6)在webView中更改所需的web url。loadUrl(“您的url hre”);在MainActivity.java

7)适用于Android studio 3.4.2版本

在棒棒糖5.0中,谷歌添加了一个官方方法WebChromeClient.onShowFileChooser。它们甚至提供了一种自动生成文件选择器意图的方法,以便它使用输入接受mime类型。

public class MyWebChromeClient extends WebChromeClient {
        // reference to activity instance. May be unnecessary if your web chrome client is member class.
    private MyActivity activity;

    public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathCallback, FileChooserParams fileChooserParams) {
        // make sure there is no existing message
        if (myActivity.uploadMessage != null) {
            myActivity.uploadMessage.onReceiveValue(null);
            myActivity.uploadMessage = null;
        }

        myActivity.uploadMessage = filePathCallback;

        Intent intent = fileChooserParams.createIntent();
        try {
            myActivity.startActivityForResult(intent, MyActivity.REQUEST_SELECT_FILE);
        } catch (ActivityNotFoundException e) {
            myActivity.uploadMessage = null;
            Toast.makeText(myActivity, "Cannot open file chooser", Toast.LENGTH_LONG).show();
            return false;
        }

        return true;
    }
}


public class MyActivity extends ... {
    public static final int REQUEST_SELECT_FILE = 100;
    public ValueCallback<Uri[]> uploadMessage;

    protected void onActivityResult(int requestCode, int resultCode, Intent data){
        if (requestCode == REQUEST_SELECT_FILE) {
                if (uploadMessage == null) return;
                uploadMessage.onReceiveValue(WebChromeClient.FileChooserParams.parseResult(resultCode, data));
                uploadMessage = null;
            }
        }
    }
}

对于KitKat之前的Android版本,其他答案中提到的私有方法是有效的。我还没有为KitKat(4.4)找到一个好的解决方案。


解决方案:https://github.com/delight-im/Android-AdvancedWebView


崩裂剂解决方案:

activity和fragment的区别只在onActivityResult中:

片段:

lateinit var webViewGlobal: AdvancedWebView private set

class WebViewFragment : Fragment(), AdvancedWebView.Listener {

private lateinit var binding: FragmentWebViewBinding

override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
    binding = FragmentWebViewBinding.inflate(inflater)
    webViewGlobal = binding.webWiew
    return binding.root
    }
}

活动:

class MainActivity : AppCompatActivity() {
    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        webViewGlobal.onActivityResult(requestCode, resultCode, data)
        super.onActivityResult(requestCode, resultCode, data)
    }
}

Android 11:

<application
       ...
       android:requestLegacyExternalStorage="true"
       ...
/>

清单:

 <uses-permission android:name="android.permission.CAMERA"/>
 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

2019:这段代码对我有效(在android 5 - 9上测试)。

package com.example.filechooser;

import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.net.http.SslError;
import android.os.Bundle;
import android.webkit.SslErrorHandler;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;


public class MainActivity extends Activity {

    // variables para manejar la subida de archivos
    private final static int FILECHOOSER_RESULTCODE = 1;
    private ValueCallback<Uri[]> mUploadMessage;

    // variable para manejar el navegador empotrado
    WebView mainWebView;


    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        // instanciamos el webview
        mainWebView = findViewById(R.id.main_web_view);

        // establecemos el cliente interno para que la navegacion no se salga de la aplicacion
        mainWebView.setWebViewClient(new MyWebViewClient());

        // establecemos el cliente chrome para seleccionar archivos
        mainWebView.setWebChromeClient(new MyWebChromeClient());

        // configuracion del webview
        mainWebView.getSettings().setJavaScriptEnabled(true);

        // cargamos la pagina
        mainWebView.loadUrl("https://example.com");
    }


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

        // manejo de seleccion de archivo
        if (requestCode == FILECHOOSER_RESULTCODE) {

            if (null == mUploadMessage || intent == null || resultCode != RESULT_OK) {
                return;
            }

            Uri[] result = null;
            String dataString = intent.getDataString();

            if (dataString != null) {
                result = new Uri[]{ Uri.parse(dataString) };
            }

            mUploadMessage.onReceiveValue(result);
            mUploadMessage = null;
        }
    }


    // ====================
    // Web clients classes
    // ====================

    /**
     * Clase para configurar el webview
     */
    private class MyWebViewClient extends WebViewClient {

        // permite la navegacion dentro del webview
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            view.loadUrl(url);
            return true;
        }
    }


    /**
     * Clase para configurar el chrome client para que nos permita seleccionar archivos
     */
    private class MyWebChromeClient extends WebChromeClient {

        // maneja la accion de seleccionar archivos
        @Override
        public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathCallback, FileChooserParams fileChooserParams) {

            // asegurar que no existan callbacks
            if (mUploadMessage != null) {
                mUploadMessage.onReceiveValue(null);
            }

            mUploadMessage = filePathCallback;

            Intent i = new Intent(Intent.ACTION_GET_CONTENT);
            i.addCategory(Intent.CATEGORY_OPENABLE);
            i.setType("*/*"); // set MIME type to filter

            MainActivity.this.startActivityForResult(Intent.createChooser(i, "File Chooser"), MainActivity.FILECHOOSER_RESULTCODE );

            return true;
        }
    }

}

希望能帮到你。

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)
    }
}