ACTION_GET_CONTENT从下载中选择文档将返回null [英] ACTION_GET_CONTENT Picking Document from Downloads returns null
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问题描述
我正在处理PDF并将其上传到服务器.从下载中选择文件时，以下代码崩溃.如果文件从任何其他目录中选择，也可以正常工作.
I am working on PDF pick and upload to server. Below code crashed when file picked from Downloads. And works fine if file choose from any other directory.
我尝试在具有(android 9)Pie OS的oneplus 6和nokia 6.1上使用以下代码.
I have tried below code on oneplus 6, and nokia 6.1 which have (android 9)Pie OS.
简而言之， 意图活动开始:
In brief code, Intent Activity start:
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("application/pdf");
intent.addCategory(Intent.CATEGORY_OPENABLE);
startActivityForResult(Intent.createChooser(intent, "Select file"), 2);
在onActivityResult
if (resultCode == Activity.RESULT_OK) {
boolean isError = false;
Uri selectedURI = data.getData();
String docPath = getPath(selectedURI);
....
}
这是整个代码getPath(Uri uri)
private String getPath(final Uri uri) {
final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
if(isKitKat) {
return getForApi19(uri);
} else if ("content".equalsIgnoreCase(uri.getScheme())) {
if (isGooglePhotosUri(uri))
return uri.getLastPathSegment();
return getDataColumn(uri, null, null);
} else if ("file".equalsIgnoreCase(uri.getScheme())) {
return uri.getPath();
}
return null;
}
@TargetApi(19)
private String getForApi19(Uri uri) {
if (DocumentsContract.isDocumentUri(this.getActivity(), uri)) {
// ExternalStorageProvider
if (isExternalStorageDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
if (docId.startsWith("raw:")) {
return docId.replaceFirst("raw:", "");
}
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);
if (id.startsWith("raw:")) {
return id.replaceFirst("raw:", "");
}
String[] contentUriPrefixesToTry = new String[]{
"content://downloads/my_downloads",
"content://downloads/public_downloads",
"content://downloads/all_downloads"
};
for (String contentUriPrefix : contentUriPrefixesToTry) {
Uri contentUri = ContentUris.withAppendedId(Uri.parse(contentUriPrefix), Long.valueOf(id));
try {
String path = getDataColumn(contentUri, null, null);
if (path != null) {
return path;
}
} catch (Exception e) {}
}
}
// MediaProvider
else if (isMediaDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
if (docId.startsWith("raw:")) {
return docId.replaceFirst("raw:", "");
}
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(contentUri, selection, selectionArgs);
}
} else if ("content".equalsIgnoreCase(uri.getScheme())) {
// Return the remote address
if (isGooglePhotosUri(uri))
return uri.getLastPathSegment();
return getDataColumn(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 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 String getDataColumn(Uri uri, String selection,
String[] selectionArgs) {
Cursor cursor = null;
String column = "_data";
final String[] projection = {column};
try {
cursor = this.getActivity().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.isClosed())
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());
}
仅content://downloads/my_downloads返回Curser对象.其他content://downloads/public_downloads和content://downloads/all_downloads返回null.
Only content://downloads/my_downloads return Curser Object. other content://downloads/public_downloads and content://downloads/all_downloads return null.
问题:
从Downloads中选择文件时，Cursor.moveToFirst()为假.而且我没有文件路径.
When file selected from Downloads the Cursor.moveToFirst() is false. and I don't get file path.
推荐答案
我遇到了同样的问题，
将以下代码用于
use below code for
if (isDownloadsDocument(uri)) {
String fileName = getFilePath(context, uri);
if (fileName != null) {
return Environment.getExternalStorageDirectory().toString() + "/Download/" + fileName;
}
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);
}
和getFilePath()
And getFilePath()
public static String getFilePath(Context context, Uri uri) {
Cursor cursor = null;
final String[] projection = {
MediaStore.MediaColumns.DISPLAY_NAME
};
try {
cursor = context.getContentResolver().query(uri, projection, null, null,
null);
if (cursor != null && cursor.moveToFirst()) {
final int index = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.DISPLAY_NAME);
return cursor.getString(index);
}
} finally {
if (cursor != null)
cursor.close();
}
return null;
}
引用:此链接
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