下载文件夹中带有文件选择器的 Android Studio 中的错误 [英] Error in Android Studio with File Chooser in Download Folder
问题描述
我的问题
我目前正在使用 Android Studio 开发 Android 应用程序.要选择一个文件，用户点击一个按钮，浏览器打开，他可以选择一个文件.对于这个过程，我使用了一个名为 FileChooser.Java 的辅助类.只要用户不从下载文件夹中选择文件，整个系统就会运行得很好.
I am currently developing an Android application with Android Studio. To choose a file the user clicks on a button, the explorer opens and he can select a file. For this process I used a helper class called FileChooser.Java. This whole system functions very well as long as the user doesn't select a file from the Download folder.
如果用户尝试从下载文件夹中选择文件，则会发生这种情况:
If the users tries to select a file from the Download folder this happens:
NumberFormatException:对于输入字符串:msf:80123"
FileChooser 返回的 URL:content://com.android.providers.downloads.documents/document/msf:80662
The URL the FileChooser returns: content://com.android.providers.downloads.documents/document/msf:80662
这是因为辅助类需要一个 long 类型.删除 msf: 并将 ID 添加到末尾也不起作用.似乎 Android 将此 msf: 标记添加到下载文件夹中的所有内容.
This is because the helper class expects a long type. Removing the msf: and adding the ID to the end doesn't work either. It seems like Android adds this msf: tag to everything in the Download folder.
我也在寻找一种有效的解决方案来调用下载文件夹中的文件.
I am looking for a valid solution to call files from the Download folder too.
电话
Uri selectedFile = data.getData();
InputStream dataStream = new FileInputStream(FileChooser.getPath(getContext(), selectedFile));
FileChooser 类中的异常调用
final Uri contentUri = ContentUris.withAppendedId(
Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
Helper 类 FileChooser
package com.example.dsvconverter.helper;
import android.content.ContentUris;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Environment;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
public class FileChooser {
/**
* 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 String[] split = id.split(":");
final String type = split[0];
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());
}
}
推荐答案
In onActivityResult() :
In onActivityResult() :
InputStream dataStream = getContentResolver().openInputStream(data.getData());
扔掉那个 getPath() 函数.
Throw away that getPath() function.
这适用于所有 uri.
This works for all uries.
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