问题
I've got to fix our App for Android N due to the FileProvider changes. I've basically read all about this topic for the last ours, but no solution found did work out for me.
Here's our prior code which starts downloads from our app, stores them in the Download folder and calls an ACTION_VIEW intent as soons as the DownloadManager tells he's finished downloading:
BroadcastReceiver onComplete = new BroadcastReceiver() {
public void onReceive(Context ctxt, Intent intent) {
Log.d(TAG, "Download commplete");
// Check for our download
long referenceId = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1);
if (mDownloadReference == referenceId) {
DownloadManager.Query query = new DownloadManager.Query();
query.setFilterById(mDownloadReference);
Cursor c = mDownloadManager.query(query);
if (c.moveToFirst()) {
int columnIndex = c.getColumnIndex(DownloadManager.COLUMN_STATUS);
if (DownloadManager.STATUS_SUCCESSFUL == c.getInt(columnIndex)) {
String localUri = c.getString(c.getColumnIndex(DownloadManager.COLUMN_LOCAL_URI));
String fileExtension = MimeTypeMap.getFileExtensionFromUrl(localUri);
String mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension(fileExtension);
if (mimeType != null) {
Intent openFileIntent = new Intent(Intent.ACTION_VIEW);
openFileIntent.setDataAndTypeAndNormalize(Uri.parse(localUri), mimeType);
openFileIntent.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
try {
mAcme.startActivity(openFileIntent);
}
catch (ActivityNotFoundException e) {
// Ignore if no activity was found.
}
}
}
}
}
}
};
This works on Android M, but breaks on N due to the popular FileUriExposedException. I've now tried to fix this by using the FileProvider, but I cannot get it to work. It's breaking when I try to get the content URI:
Failed to find configured root that contains /file:/storage/emulated/0/Download/test.pdf
The localUri returned from the DownloadManager for the file is:
file:///storage/emulated/0/Download/test.pdf
The Environment.getExternalStorageDirectory() returns /storage/emulated/0 and this is the code for the conversion:
File file = new File(localUri);
Log.d(TAG, localUri + " - " + Environment.getExternalStorageDirectory());
Uri contentUri = FileProvider.getUriForFile(ctxt, "my.file.provider", file);
From AndroidManifest.xml
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="my.file.provider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/file_paths"/>
</provider>
The file_paths.xml:
<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
<external-path name="external_path" path="." />
</paths>
And I've tried all values I could find in that xml file. :(
回答1:
Thanks to @greenaps I was able to solve the issue. The local URI retrieved from the DownlodManager was prefixed with file://. This has to be dropped for the new FileProvider:
if (localUri.substring(0, 7).matches("file://")) {
localUri = localUri.substring(7);
}
File file = new File(localUri);
回答2:
here change in AndroidManifest.xml
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="${applicationId}.provider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/file_paths"/>
</provider>
change in file path
Uri contentUri;
if(Build.VERSION.SDK_INT == 24){
contentUri = FileProvider.getUriForFile(MainActivity.this,
getApplicationContext().getPackageName() + ".provider",
file);
} else{
contentUri = Uri.fromFile(file);
}
回答3:
How to get file exact path filename. lower and higher device.
public class RealPathUtil {
public static String getRealPath(Context context, Uri fileUri) {
String realPath;
// SDK < API11
if (Build.VERSION.SDK_INT < 11) {
realPath = RealPathUtil.getRealPathFromURI_BelowAPI11(context, fileUri);
}
// SDK >= 11 && SDK < 19
else if (Build.VERSION.SDK_INT < 19) {
realPath = RealPathUtil.getRealPathFromURI_API11to18(context, fileUri);
}
// SDK > 19 (Android 4.4) and up
else {
realPath = RealPathUtil.getRealPathFromURI_API19(context, fileUri);
}
return realPath;
}
@SuppressLint("NewApi")
public static String getRealPathFromURI_API11to18(Context context, Uri contentUri) {
String[] proj = {MediaStore.Images.Media.DATA};
String result = null;
CursorLoader cursorLoader = new CursorLoader(context, contentUri, proj, null, null, null);
Cursor cursor = cursorLoader.loadInBackground();
if (cursor != null) {
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
result = cursor.getString(column_index);
cursor.close();
}
return result;
}
public static String getRealPathFromURI_BelowAPI11(Context context, Uri contentUri) {
String[] proj = {MediaStore.Images.Media.DATA};
Cursor cursor = context.getContentResolver().query(contentUri, proj, null, null, null);
int column_index = 0;
String result = "";
if (cursor != null) {
column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
result = cursor.getString(column_index);
cursor.close();
return result;
}
return result;
}
/**
* Get a file path from a Uri. This will get the the path for Storage Access
* Framework Documents, as well as the _data field for the MediaStore and
* other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @author paulburke
*/
@SuppressLint("NewApi")
public static String getRealPathFromURI_API19(final Context context, final Uri uri) {
final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
// DocumentProvider
if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
// ExternalStorageProvider
if (isExternalStorageDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
if ("primary".equalsIgnoreCase(type)) {
return Environment.getExternalStorageDirectory() + "/" + split[1];
}
// TODO handle non-primary volumes
}
// DownloadsProvider
else if (isDownloadsDocument(uri)) {
final String id = DocumentsContract.getDocumentId(uri);
final Uri contentUri = ContentUris.withAppendedId(
Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
return getDataColumn(context, contentUri, null, null);
}
// MediaProvider
else if (isMediaDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
Uri contentUri = null;
if ("image".equals(type)) {
contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
} else if ("video".equals(type)) {
contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
} else if ("audio".equals(type)) {
contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
}
final String selection = "_id=?";
final String[] selectionArgs = new String[]{
split[1]
};
return getDataColumn(context, contentUri, selection, selectionArgs);
}
}
// MediaStore (and general)
else if ("content".equalsIgnoreCase(uri.getScheme())) {
// Return the remote address
if (isGooglePhotosUri(uri))
return uri.getLastPathSegment();
return getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
return uri.getPath();
}
return null;
}
/**
* Get the value of the data column for this Uri. This is useful for
* MediaStore Uris, and other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @param selection (Optional) Filter used in the query.
* @param selectionArgs (Optional) Selection arguments used in the query.
* @return The value of the _data column, which is typically a file path.
*/
public static String getDataColumn(Context context, Uri uri, String selection,
String[] selectionArgs) {
Cursor cursor = null;
final String column = "_data";
final String[] projection = {
column
};
try {
cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
null);
if (cursor != null && cursor.moveToFirst()) {
final int index = cursor.getColumnIndexOrThrow(column);
return cursor.getString(index);
}
} finally {
if (cursor != null)
cursor.close();
}
return null;
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is ExternalStorageProvider.
*/
public static boolean isExternalStorageDocument(Uri uri) {
return "com.android.externalstorage.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is DownloadsProvider.
*/
public static boolean isDownloadsDocument(Uri uri) {
return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is MediaProvider.
*/
public static boolean isMediaDocument(Uri uri) {
return "com.android.providers.media.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is Google Photos.
*/
public static boolean isGooglePhotosUri(Uri uri) {
return "com.google.android.apps.photos.content".equals(uri.getAuthority());
}
}
This is exact solution. Just call Uri selectedResume = data.getData(); String mediaResumePath = RealPathUtil.getRealPath(this, selectedResume);
回答4:
I had a similar issue and solved it by not automatically opening the file but showing the 'Download complete' notification and then let the Android system open the file when the user clicks on the notification.
To notify the user additionally, I'm showing a Toast when the download is completed.
DownloadManager mManager = (DownloadManager) context.getSystemService(Context.DOWNLOAD_SERVICE);
String url = "your URL";
String filename = "file.pdf";
// Set up the request.
DownloadManager.Request request = new DownloadManager.Request(Uri.parse(url))
.setTitle("Test")
.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, filename)
.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED)
.setDescription("Downloading...")
.setMimeType("application/pdf");
request.allowScanningByMediaScanner();
mManager.enqueue(request);
BroadcastReceiver:
public class DownloadReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
switch (intent.getAction()) {
case DownloadManager.ACTION_DOWNLOAD_COMPLETE:
Toast.makeText(context, "Download completed", Toast.LENGTH_SHORT).show();
break;
}
}
}
回答5:
Can be this clearer solution ?
Uri uriParser = Uri.parse(downloadedPackageUriString);
File downloadedFile = new File(uriParser.getPath());
before
file:///storage/emulated/0/Download/ZS%20Gac%C3%ADkov%C3%A1.pdf
after
/storage/emulated/0/Download/ZS Gacíková.pdf
来源：https://stackoverflow.com/questions/39996491/open-downloaded-file-on-android-n-using-fileprovider