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">
<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
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。
其他回答
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。
这是我的工作。也适用于牛轧糖和棉花糖[[
import android.Manifest;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.res.Configuration;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
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.Toast;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
public class MainActivity extends AppCompatActivity {
private static final String TAG = MainActivity.class.getSimpleName();
private final static int FCR = 1;
WebView webView;
private String mCM;
private ValueCallback<Uri> mUM;
private ValueCallback<Uri[]> mUMA;
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
super.onActivityResult(requestCode, resultCode, intent);
if (Build.VERSION.SDK_INT >= 21) {
Uri[] results = null;
//Check if response is positive
if (resultCode == Activity.RESULT_OK) {
if (requestCode == FCR) {
if (null == mUMA) {
return;
}
if (intent == null) {
//Capture Photo if no image available
if (mCM != null) {
results = new Uri[]{Uri.parse(mCM)};
}
} else {
String dataString = intent.getDataString();
if (dataString != null) {
results = new Uri[]{Uri.parse(dataString)};
}
}
}
}
mUMA.onReceiveValue(results);
mUMA = null;
} else {
if (requestCode == FCR) {
if (null == mUM) return;
Uri result = intent == null || resultCode != RESULT_OK ? null : intent.getData();
mUM.onReceiveValue(result);
mUM = null;
}
}
}
@SuppressLint({"SetJavaScriptEnabled", "WrongViewCast"})
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (Build.VERSION.SDK_INT >= 23 && (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED || ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED)) {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE, Manifest.permission.CAMERA}, 1);
}
webView = (WebView) findViewById(R.id.ifView);
assert webView != null;
WebSettings webSettings = webView.getSettings();
webSettings.setJavaScriptEnabled(true);
webSettings.setAllowFileAccess(true);
if (Build.VERSION.SDK_INT >= 21) {
webSettings.setMixedContentMode(0);
webView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
} else if (Build.VERSION.SDK_INT >= 19) {
webView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
} else if (Build.VERSION.SDK_INT < 19) {
webView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
}
webView.setWebViewClient(new Callback());
webView.loadUrl("https://infeeds.com/");
webView.setWebChromeClient(new WebChromeClient() {
//For Android 3.0+
public void openFileChooser(ValueCallback<Uri> uploadMsg) {
mUM = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("*/*");
MainActivity.this.startActivityForResult(Intent.createChooser(i, "File Chooser"), FCR);
}
// For Android 3.0+, above method not supported in some android 3+ versions, in such case we use this
public void openFileChooser(ValueCallback uploadMsg, String acceptType) {
mUM = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("*/*");
MainActivity.this.startActivityForResult(
Intent.createChooser(i, "File Browser"),
FCR);
}
//For Android 4.1+
public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) {
mUM = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("*/*");
MainActivity.this.startActivityForResult(Intent.createChooser(i, "File Chooser"), MainActivity.FCR);
}
//For Android 5.0+
public boolean onShowFileChooser(
WebView webView, ValueCallback<Uri[]> filePathCallback,
WebChromeClient.FileChooserParams fileChooserParams) {
if (mUMA != null) {
mUMA.onReceiveValue(null);
}
mUMA = filePathCallback;
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
if (takePictureIntent.resolveActivity(MainActivity.this.getPackageManager()) != null) {
File photoFile = null;
try {
photoFile = createImageFile();
takePictureIntent.putExtra("PhotoPath", mCM);
} catch (IOException ex) {
Log.e(TAG, "Image file creation failed", ex);
}
if (photoFile != null) {
mCM = "file:" + photoFile.getAbsolutePath();
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photoFile));
} else {
takePictureIntent = null;
}
}
Intent contentSelectionIntent = new Intent(Intent.ACTION_GET_CONTENT);
contentSelectionIntent.addCategory(Intent.CATEGORY_OPENABLE);
contentSelectionIntent.setType("*/*");
Intent[] intentArray;
if (takePictureIntent != null) {
intentArray = new Intent[]{takePictureIntent};
} else {
intentArray = new Intent[0];
}
Intent chooserIntent = new Intent(Intent.ACTION_CHOOSER);
chooserIntent.putExtra(Intent.EXTRA_INTENT, contentSelectionIntent);
chooserIntent.putExtra(Intent.EXTRA_TITLE, "Image Chooser");
chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, intentArray);
startActivityForResult(chooserIntent, FCR);
return true;
}
});
}
// Create an image file
private File createImageFile() throws IOException {
@SuppressLint("SimpleDateFormat") String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imageFileName = "img_" + timeStamp + "_";
File storageDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
return File.createTempFile(imageFileName, ".jpg", storageDir);
}
@Override
public boolean onKeyDown(int keyCode, @NonNull KeyEvent event) {
if (event.getAction() == KeyEvent.ACTION_DOWN) {
switch (keyCode) {
case KeyEvent.KEYCODE_BACK:
if (webView.canGoBack()) {
webView.goBack();
} else {
finish();
}
return true;
}
}
return super.onKeyDown(keyCode, event);
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
}
public class Callback extends WebViewClient {
public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
Toast.makeText(getApplicationContext(), "Failed loading app!", Toast.LENGTH_SHORT).show();
}
}
}
你访问过这个链接吗? http://groups.google.com/group/android-developers/browse_thread/thread/dcaf8b2fdd8a90c4/62d5e2ffef31ebdb
http://moazzam-khan.com/blog/?tag=android-upload-file
http://evgenyg.wordpress.com/2010/05/01/uploading-files-multipart-post-apache/
通过javalib Apache Commons上传文件的简明示例
我想你会从中得到帮助的
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)
}
}
这个解决方案也适用于蜂窝和冰淇淋三明治。似乎谷歌引入了一个很酷的新特性(accept属性)，并且忘记实现向后兼容性的重载。
protected class CustomWebChromeClient extends WebChromeClient
{
// For Android 3.0+
public void openFileChooser( ValueCallback<Uri> uploadMsg, String acceptType )
{
context.mUploadMessage = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
context.startActivityForResult( Intent.createChooser( i, "File Chooser" ), MainActivity.FILECHOOSER_RESULTCODE );
}
// For Android < 3.0
public void openFileChooser( ValueCallback<Uri> uploadMsg )
{
openFileChooser( uploadMsg, "" );
}
}
