WebView中的文件上载
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自从过去几天以来，我一直在努力从WebView上传文件，但没有任何进展。我用谷歌搜索并实现了所有建议的解决方案，但没有一个工作，如：解决方案建议here，等等。
问题：我有一个带有以下代码的html页面来上传文件。它在Firefox等桌面浏览器和模拟器/ AVD的内置浏览器中工作正常，当我点击元素呈现的“浏览...”按钮时，浏览器会打开一个对话框，我可以在其中选择要上传的文件。
但是，在android 3.0模拟器/ AVD中，当我点击“选择文件”时，没有任何反应，没有打开文件对话框！
<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>
有人可以最早建议一个可能的解决方案。
答案
这是所有Android版本的完整解决方案，我也很难。
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);
}*/
}
另外我想补充一点，这个例子中的“上传页面”不适用于<4个版本，因为它有图像预览功能，如果你想让它工作使用简单的php上传而不预览。
更新：
请找到棒棒糖设备here的解决方案，并感谢gauntface
更新2：
所有Android设备的完整解决方案，直到oreo here和this is more advanced version，你应该调查它，也许它可以帮助。
另一答案
这对我有用。也适用于Nougat和Marshmallow
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.requ以上是关于WebView中的文件上载的主要内容，如果未能解决你的问题，请参考以下文章
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