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
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
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。
这是一个完整的解决方案，所有的android版本，我有一个艰难的时间与此。
public class MyWb extends Activity {
/** Called when the activity is first created. */
WebView web;
ProgressBar progressBar;
private ValueCallback<Uri> mUploadMessage;
private final static int FILECHOOSER_RESULTCODE=1;
@Override
protected void onActivityResult(int requestCode, int resultCode,
Intent intent) {
if(requestCode==FILECHOOSER_RESULTCODE)
{
if (null == mUploadMessage) return;
Uri result = intent == null || resultCode != RESULT_OK ? null
: intent.getData();
mUploadMessage.onReceiveValue(result);
mUploadMessage = null;
}
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
web = (WebView) findViewById(R.id.webview01);
progressBar = (ProgressBar) findViewById(R.id.progressBar1);
web = new WebView(this);
web.getSettings().setJavaScriptEnabled(true);
web.loadUrl("http://www.script-tutorials.com/demos/199/index.html");
web.setWebViewClient(new myWebClient());
web.setWebChromeClient(new WebChromeClient()
{
//The undocumented magic method override
//Eclipse will swear at you if you try to put @Override here
// For Android 3.0+
public void openFileChooser(ValueCallback<Uri> uploadMsg) {
mUploadMessage = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
MyWb.this.startActivityForResult(Intent.createChooser(i,"File Chooser"), FILECHOOSER_RESULTCODE);
}
// For Android 3.0+
public void openFileChooser( ValueCallback uploadMsg, String acceptType ) {
mUploadMessage = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("*/*");
MyWb.this.startActivityForResult(
Intent.createChooser(i, "File Browser"),
FILECHOOSER_RESULTCODE);
}
//For Android 4.1
public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture){
mUploadMessage = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
MyWb.this.startActivityForResult( Intent.createChooser( i, "File Chooser" ), MyWb.FILECHOOSER_RESULTCODE );
}
});
setContentView(web);
}
public class myWebClient extends WebViewClient
{
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
// TODO Auto-generated method stub
super.onPageStarted(view, url, favicon);
}
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
// TODO Auto-generated method stub
view.loadUrl(url);
return true;
}
@Override
public void onPageFinished(WebView view, String url) {
// TODO Auto-generated method stub
super.onPageFinished(view, url);
progressBar.setVisibility(View.GONE);
}
}
//flipscreen not loading again
@Override
public void onConfigurationChanged(Configuration newConfig){
super.onConfigurationChanged(newConfig);
}
// To handle "Back" key press event for WebView to go back to previous screen.
/*@Override
public boolean onKeyDown(int keyCode, KeyEvent event)
{
if ((keyCode == KeyEvent.KEYCODE_BACK) && web.canGoBack()) {
web.goBack();
return true;
}
return super.onKeyDown(keyCode, event);
}*/
}
我还想补充一点，像这个例子中的“上传页面”，不会在< 4个版本上工作，因为它有一个图像预览功能，如果你想让它工作，使用一个简单的php上传没有预览。
更新:
请在这里找到棒棒糖装置的解决方案，感谢gauntface
更新2:
完整的解决方案，所有android设备，直到奥利奥这里，这是更高级的版本，你应该看看，也许它可以帮助。
我是android的新手，在这方面也很吃力。根据谷歌参考指南WebView。
默认情况下，WebView不提供类似浏览器的小部件 启用JavaScript和网页错误被忽略。如果你的目标是 只是显示一些HTML作为你的UI的一部分，这可能是好的; 除了阅读，用户不需要与网页进行交互， 网页也不需要与用户交互。如果你真的 想要一个成熟的web浏览器，那么您可能需要调用 浏览器应用程序的URL意图，而不是显示它与 WebView。
我在mainactivity .java中执行的示例代码。
Uri uri = Uri.parse("https://www.example.com");
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
Excuted
package example.com.myapp;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.content.Intent;
import android.net.Uri;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Uri uri = Uri.parse("http://www.example.com/");
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
getSupportActionBar().hide();
}}
这是我发现的唯一有效的解决方案!
WebView webview;
private ValueCallback<Uri> mUploadMessage;
private final static int FILECHOOSER_RESULTCODE = 1;
@Override
protected void onActivityResult(int requestCode, int resultCode,
Intent intent) {
if (requestCode == FILECHOOSER_RESULTCODE) {
if (null == mUploadMessage)
return;
Uri result = intent == null || resultCode != RESULT_OK ? null
: intent.getData();
mUploadMessage.onReceiveValue(result);
mUploadMessage = null;
}
}
// Next part
class MyWebChromeClient extends WebChromeClient {
// The undocumented magic method override
// Eclipse will swear at you if you try to put @Override here
public void openFileChooser(ValueCallback<Uri> uploadMsg) {
mUploadMessage = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
Cv5appActivity.this.startActivityForResult(
Intent.createChooser(i, "Image Browser"),
FILECHOOSER_RESULTCODE);
}
}
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”。
