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
在奇巧，你可以使用存储访问框架。
存储访问框架/编写客户端应用程序
其他回答
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);
}
}
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();
}}
谷歌自己的浏览器为这个问题提供了一个全面的解决方案，它保证了自己的类:
openFileChooser在Android 4.0.4中的实现
android4.0.4中的UploadHandler类
蜂窝(API 11)到Android 11的工作方法
由swati vishnoi更新，这适用于派和以上
static WebView mWebView;
private ValueCallback<Uri> mUploadMessage;
public ValueCallback<Uri[]> uploadMessage;
public static final int REQUEST_SELECT_FILE = 100;
private final static int FILECHOOSER_RESULTCODE = 1;
修改onActivityResult ()
@Override
public void onActivityResult(int requestCode, int resultCode, Intent intent)
{
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)
{
if (requestCode == REQUEST_SELECT_FILE)
{
if (uploadMessage == null)
return;
uploadMessage.onReceiveValue(WebChromeClient.FileChooserParams.parseResult(resultCode, intent));
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
Uri result = intent == null || resultCode != MainActivity.RESULT_OK ? null : intent.getData();
mUploadMessage.onReceiveValue(result);
mUploadMessage = null;
}
else
Toast.makeText(getActivity().getApplicationContext(), "Failed to Upload Image", Toast.LENGTH_LONG).show();
}
现在在onCreate()或onCreateView()中粘贴以下代码
WebSettings mWebSettings = mWebView.getSettings();
mWebSettings.setJavaScriptEnabled(true);
mWebSettings.setSupportZoom(false);
mWebSettings.setAllowFileAccess(true);
mWebSettings.setAllowContentAccess(true);
mWebView.setWebChromeClient(new WebChromeClient()
{
// For 3.0+ Devices (Start)
// onActivityResult attached before constructor
protected void openFileChooser(ValueCallback uploadMsg, String acceptType)
{
mUploadMessage = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
startActivityForResult(Intent.createChooser(i, "File Browser"), FILECHOOSER_RESULTCODE);
}
// For Lollipop 5.0+ Devices
public boolean onShowFileChooser(WebView mWebView, ValueCallback<Uri[]> filePathCallback, WebChromeClient.FileChooserParams fileChooserParams)
{
if (uploadMessage != null) {
uploadMessage.onReceiveValue(null);
uploadMessage = null;
}
uploadMessage = filePathCallback;
Intent intent = fileChooserParams.createIntent();
try
{
startActivityForResult(intent, REQUEST_SELECT_FILE);
} catch (ActivityNotFoundException e)
{
uploadMessage = null;
Toast.makeText(getActivity().getApplicationContext(), "Cannot Open File Chooser", Toast.LENGTH_LONG).show();
return false;
}
return true;
}
//For Android 4.1 only
protected void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture)
{
mUploadMessage = uploadMsg;
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/*");
startActivityForResult(Intent.createChooser(intent, "File Browser"), FILECHOOSER_RESULTCODE);
}
protected void openFileChooser(ValueCallback<Uri> uploadMsg)
{
mUploadMessage = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
startActivityForResult(Intent.createChooser(i, "File Chooser"), FILECHOOSER_RESULTCODE);
}
});
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。
