文件返回空 ( " " ) 时从 Android 中的意图中进行选择

Question

我正在尝试上传视频。我所做的是，我已经下载了一个示例视频并尝试使用意图选择视频。我期待的是我选择的文件，我会得到它并传递给网络并上传。由于我以前没有任何这样做的经验，所以我很难处理它。

private void getFile() {
Intent intent = new Intent();
intent.setType("video/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Video"), REQUEST_CODE_PICKER);
}

当我选择视频时，我收到一个urionActivityResult

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == Activity.RESULT_OK) {
Uri uri = data.getData();
String uriPath = uri.getPath(); // uriPath = "/document/video:7876"
File fileToUpload = new File(uriPath); // fileToUpload = ""
String videoPath = getRealVideoPathFromURI(getContentResolver(),uri); // videoPath = "/storage/emulated/0/Download/testVideo.mp4"
File videoFile = new File(videoPath); // videoFile = ""
uploadFile(videoFile);
}
}

我尝试了两个路径(realPath和uriPath(以查看我是否得到任何文件。如果我调试，我可以看到文件上传和视频文件都是"。要添加，将给出所有读取和写入权限。

这是从URI获取真实视频路径的代码

String getRealVideoPathFromURI(ContentResolver contentResolver ,
Uri contentURI){
Cursor cursor = contentResolver.query(contentURI, null, null, null, null);
if (cursor == null)
return contentURI.getPath();
else {
cursor.moveToFirst();
int idx = cursor.getColumnIndex(MediaStore.Video.VideoColumns.DATA);
try {
return cursor.getString(idx);
} catch (Exception exception) {
return null;
}
}
}

谁能帮助我了解我做错了什么？我所需要做的就是上传选定的视频文件。我的做法是错的吗？如果是这样，那么正确的方法是什么？由于我不在没有搜索的情况下提出问题并且未能找到，请尝试给我正确的答案，这可以帮助我解决这个问题。可能是我的方法错误，可能是某些设备问题等。谢谢

Answer 1

使用以下代码获取 Path。

此外，您还应该在新File(getPath(this，data.getData(((中传递realpath。

/**
* 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
*/
public static String getPath(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 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 column_index = cursor.getColumnIndexOrThrow(column);
return cursor.getString(column_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());
}