| /* |
| * Copyright (C) 2013 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| |
| package com.example.android.storageprovider; |
| |
| import android.content.Context; |
| import android.content.SharedPreferences; |
| import android.content.res.AssetFileDescriptor; |
| import android.content.res.TypedArray; |
| import android.database.Cursor; |
| import android.database.MatrixCursor; |
| import android.graphics.Point; |
| import android.os.CancellationSignal; |
| import android.os.Handler; |
| import android.os.ParcelFileDescriptor; |
| import android.provider.DocumentsContract.Document; |
| import android.provider.DocumentsContract.Root; |
| import android.provider.DocumentsProvider; |
| import android.webkit.MimeTypeMap; |
| |
| import com.example.android.common.logger.Log; |
| |
| import java.io.ByteArrayOutputStream; |
| import java.io.File; |
| import java.io.FileNotFoundException; |
| import java.io.FileOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.util.Collections; |
| import java.util.Comparator; |
| import java.util.HashSet; |
| import java.util.LinkedList; |
| import java.util.PriorityQueue; |
| import java.util.Set; |
| |
| /** |
| * Manages documents and exposes them to the Android system for sharing. |
| */ |
| public class MyCloudProvider extends DocumentsProvider { |
| private static final String TAG = MyCloudProvider.class.getSimpleName(); |
| |
| // Use these as the default columns to return information about a root if no specific |
| // columns are requested in a query. |
| private static final String[] DEFAULT_ROOT_PROJECTION = new String[]{ |
| Root.COLUMN_ROOT_ID, |
| Root.COLUMN_MIME_TYPES, |
| Root.COLUMN_FLAGS, |
| Root.COLUMN_ICON, |
| Root.COLUMN_TITLE, |
| Root.COLUMN_SUMMARY, |
| Root.COLUMN_DOCUMENT_ID, |
| Root.COLUMN_AVAILABLE_BYTES |
| }; |
| |
| // Use these as the default columns to return information about a document if no specific |
| // columns are requested in a query. |
| private static final String[] DEFAULT_DOCUMENT_PROJECTION = new String[]{ |
| Document.COLUMN_DOCUMENT_ID, |
| Document.COLUMN_MIME_TYPE, |
| Document.COLUMN_DISPLAY_NAME, |
| Document.COLUMN_LAST_MODIFIED, |
| Document.COLUMN_FLAGS, |
| Document.COLUMN_SIZE |
| }; |
| |
| // No official policy on how many to return, but make sure you do limit the number of recent |
| // and search results. |
| private static final int MAX_SEARCH_RESULTS = 20; |
| private static final int MAX_LAST_MODIFIED = 5; |
| |
| private static final String ROOT = "root"; |
| |
| // A file object at the root of the file hierarchy. Depending on your implementation, the root |
| // does not need to be an existing file system directory. For example, a tag-based document |
| // provider might return a directory containing all tags, represented as child directories. |
| private File mBaseDir; |
| |
| @Override |
| public boolean onCreate() { |
| Log.v(TAG, "onCreate"); |
| |
| mBaseDir = getContext().getFilesDir(); |
| |
| writeDummyFilesToStorage(); |
| |
| return true; |
| } |
| |
| // BEGIN_INCLUDE(query_roots) |
| @Override |
| public Cursor queryRoots(String[] projection) throws FileNotFoundException { |
| Log.v(TAG, "queryRoots"); |
| |
| // Create a cursor with either the requested fields, or the default projection. This |
| // cursor is returned to the Android system picker UI and used to display all roots from |
| // this provider. |
| final MatrixCursor result = new MatrixCursor(resolveRootProjection(projection)); |
| |
| // If user is not logged in, return an empty root cursor. This removes our provider from |
| // the list entirely. |
| if (!isUserLoggedIn()) { |
| return result; |
| } |
| |
| // It's possible to have multiple roots (e.g. for multiple accounts in the same app) - |
| // just add multiple cursor rows. |
| // Construct one row for a root called "MyCloud". |
| final MatrixCursor.RowBuilder row = result.newRow(); |
| |
| row.add(Root.COLUMN_ROOT_ID, ROOT); |
| row.add(Root.COLUMN_SUMMARY, getContext().getString(R.string.root_summary)); |
| |
| // FLAG_SUPPORTS_CREATE means at least one directory under the root supports creating |
| // documents. FLAG_SUPPORTS_RECENTS means your application's most recently used |
| // documents will show up in the "Recents" category. FLAG_SUPPORTS_SEARCH allows users |
| // to search all documents the application shares. |
| row.add(Root.COLUMN_FLAGS, Root.FLAG_SUPPORTS_CREATE | |
| Root.FLAG_SUPPORTS_RECENTS | |
| Root.FLAG_SUPPORTS_SEARCH); |
| |
| // COLUMN_TITLE is the root title (e.g. what will be displayed to identify your provider). |
| row.add(Root.COLUMN_TITLE, getContext().getString(R.string.app_name)); |
| |
| // This document id must be unique within this provider and consistent across time. The |
| // system picker UI may save it and refer to it later. |
| row.add(Root.COLUMN_DOCUMENT_ID, getDocIdForFile(mBaseDir)); |
| |
| // The child MIME types are used to filter the roots and only present to the user roots |
| // that contain the desired type somewhere in their file hierarchy. |
| row.add(Root.COLUMN_MIME_TYPES, getChildMimeTypes(mBaseDir)); |
| row.add(Root.COLUMN_AVAILABLE_BYTES, mBaseDir.getFreeSpace()); |
| row.add(Root.COLUMN_ICON, R.drawable.ic_launcher); |
| |
| return result; |
| } |
| // END_INCLUDE(query_roots) |
| |
| // BEGIN_INCLUDE(query_recent_documents) |
| @Override |
| public Cursor queryRecentDocuments(String rootId, String[] projection) |
| throws FileNotFoundException { |
| Log.v(TAG, "queryRecentDocuments"); |
| |
| // This example implementation walks a local file structure to find the most recently |
| // modified files. Other implementations might include making a network call to query a |
| // server. |
| |
| // Create a cursor with the requested projection, or the default projection. |
| final MatrixCursor result = new MatrixCursor(resolveDocumentProjection(projection)); |
| |
| final File parent = getFileForDocId(rootId); |
| |
| // Create a queue to store the most recent documents, which orders by last modified. |
| PriorityQueue<File> lastModifiedFiles = new PriorityQueue<File>(5, new Comparator<File>() { |
| public int compare(File i, File j) { |
| return Long.compare(i.lastModified(), j.lastModified()); |
| } |
| }); |
| |
| // Iterate through all files and directories in the file structure under the root. If |
| // the file is more recent than the least recently modified, add it to the queue, |
| // limiting the number of results. |
| final LinkedList<File> pending = new LinkedList<File>(); |
| |
| // Start by adding the parent to the list of files to be processed |
| pending.add(parent); |
| |
| // Do while we still have unexamined files |
| while (!pending.isEmpty()) { |
| // Take a file from the list of unprocessed files |
| final File file = pending.removeFirst(); |
| if (file.isDirectory()) { |
| // If it's a directory, add all its children to the unprocessed list |
| Collections.addAll(pending, file.listFiles()); |
| } else { |
| // If it's a file, add it to the ordered queue. |
| lastModifiedFiles.add(file); |
| } |
| } |
| |
| // Add the most recent files to the cursor, not exceeding the max number of results. |
| for (int i = 0; i < Math.min(MAX_LAST_MODIFIED + 1, lastModifiedFiles.size()); i++) { |
| final File file = lastModifiedFiles.remove(); |
| includeFile(result, null, file); |
| } |
| return result; |
| } |
| // END_INCLUDE(query_recent_documents) |
| |
| // BEGIN_INCLUDE(query_search_documents) |
| @Override |
| public Cursor querySearchDocuments(String rootId, String query, String[] projection) |
| throws FileNotFoundException { |
| Log.v(TAG, "querySearchDocuments"); |
| |
| // Create a cursor with the requested projection, or the default projection. |
| final MatrixCursor result = new MatrixCursor(resolveDocumentProjection(projection)); |
| final File parent = getFileForDocId(rootId); |
| |
| // This example implementation searches file names for the query and doesn't rank search |
| // results, so we can stop as soon as we find a sufficient number of matches. Other |
| // implementations might use other data about files, rather than the file name, to |
| // produce a match; it might also require a network call to query a remote server. |
| |
| // Iterate through all files in the file structure under the root until we reach the |
| // desired number of matches. |
| final LinkedList<File> pending = new LinkedList<File>(); |
| |
| // Start by adding the parent to the list of files to be processed |
| pending.add(parent); |
| |
| // Do while we still have unexamined files, and fewer than the max search results |
| while (!pending.isEmpty() && result.getCount() < MAX_SEARCH_RESULTS) { |
| // Take a file from the list of unprocessed files |
| final File file = pending.removeFirst(); |
| if (file.isDirectory()) { |
| // If it's a directory, add all its children to the unprocessed list |
| Collections.addAll(pending, file.listFiles()); |
| } else { |
| // If it's a file and it matches, add it to the result cursor. |
| if (file.getName().toLowerCase().contains(query)) { |
| includeFile(result, null, file); |
| } |
| } |
| } |
| return result; |
| } |
| // END_INCLUDE(query_search_documents) |
| |
| // BEGIN_INCLUDE(open_document_thumbnail) |
| @Override |
| public AssetFileDescriptor openDocumentThumbnail(String documentId, Point sizeHint, |
| CancellationSignal signal) |
| throws FileNotFoundException { |
| Log.v(TAG, "openDocumentThumbnail"); |
| |
| final File file = getFileForDocId(documentId); |
| final ParcelFileDescriptor pfd = |
| ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY); |
| return new AssetFileDescriptor(pfd, 0, AssetFileDescriptor.UNKNOWN_LENGTH); |
| } |
| // END_INCLUDE(open_document_thumbnail) |
| |
| // BEGIN_INCLUDE(query_document) |
| @Override |
| public Cursor queryDocument(String documentId, String[] projection) |
| throws FileNotFoundException { |
| Log.v(TAG, "queryDocument"); |
| |
| // Create a cursor with the requested projection, or the default projection. |
| final MatrixCursor result = new MatrixCursor(resolveDocumentProjection(projection)); |
| includeFile(result, documentId, null); |
| return result; |
| } |
| // END_INCLUDE(query_document) |
| |
| // BEGIN_INCLUDE(query_child_documents) |
| @Override |
| public Cursor queryChildDocuments(String parentDocumentId, String[] projection, |
| String sortOrder) throws FileNotFoundException { |
| Log.v(TAG, "queryChildDocuments, parentDocumentId: " + |
| parentDocumentId + |
| " sortOrder: " + |
| sortOrder); |
| |
| final MatrixCursor result = new MatrixCursor(resolveDocumentProjection(projection)); |
| final File parent = getFileForDocId(parentDocumentId); |
| for (File file : parent.listFiles()) { |
| includeFile(result, null, file); |
| } |
| return result; |
| } |
| // END_INCLUDE(query_child_documents) |
| |
| |
| // BEGIN_INCLUDE(open_document) |
| @Override |
| public ParcelFileDescriptor openDocument(final String documentId, final String mode, |
| CancellationSignal signal) |
| throws FileNotFoundException { |
| Log.v(TAG, "openDocument, mode: " + mode); |
| // It's OK to do network operations in this method to download the document, as long as you |
| // periodically check the CancellationSignal. If you have an extremely large file to |
| // transfer from the network, a better solution may be pipes or sockets |
| // (see ParcelFileDescriptor for helper methods). |
| |
| final File file = getFileForDocId(documentId); |
| final int accessMode = ParcelFileDescriptor.parseMode(mode); |
| |
| final boolean isWrite = (mode.indexOf('w') != -1); |
| if (isWrite) { |
| // Attach a close listener if the document is opened in write mode. |
| try { |
| Handler handler = new Handler(getContext().getMainLooper()); |
| return ParcelFileDescriptor.open(file, accessMode, handler, |
| new ParcelFileDescriptor.OnCloseListener() { |
| @Override |
| public void onClose(IOException e) { |
| |
| // Update the file with the cloud server. The client is done writing. |
| Log.i(TAG, "A file with id " + documentId + " has been closed! Time to " + |
| "update the server."); |
| } |
| |
| }); |
| } catch (IOException e) { |
| throw new FileNotFoundException("Failed to open document with id " + documentId + |
| " and mode " + mode); |
| } |
| } else { |
| return ParcelFileDescriptor.open(file, accessMode); |
| } |
| } |
| // END_INCLUDE(open_document) |
| |
| |
| // BEGIN_INCLUDE(create_document) |
| @Override |
| public String createDocument(String documentId, String mimeType, String displayName) |
| throws FileNotFoundException { |
| Log.v(TAG, "createDocument"); |
| |
| File parent = getFileForDocId(documentId); |
| File file = new File(parent.getPath(), displayName); |
| try { |
| file.createNewFile(); |
| file.setWritable(true); |
| file.setReadable(true); |
| } catch (IOException e) { |
| throw new FileNotFoundException("Failed to create document with name " + |
| displayName +" and documentId " + documentId); |
| } |
| return getDocIdForFile(file); |
| } |
| // END_INCLUDE(create_document) |
| |
| // BEGIN_INCLUDE(delete_document) |
| @Override |
| public void deleteDocument(String documentId) throws FileNotFoundException { |
| Log.v(TAG, "deleteDocument"); |
| File file = getFileForDocId(documentId); |
| if (file.delete()) { |
| Log.i(TAG, "Deleted file with id " + documentId); |
| } else { |
| throw new FileNotFoundException("Failed to delete document with id " + documentId); |
| } |
| } |
| // END_INCLUDE(delete_document) |
| |
| |
| @Override |
| public String getDocumentType(String documentId) throws FileNotFoundException { |
| File file = getFileForDocId(documentId); |
| return getTypeForFile(file); |
| } |
| |
| /** |
| * @param projection the requested root column projection |
| * @return either the requested root column projection, or the default projection if the |
| * requested projection is null. |
| */ |
| private static String[] resolveRootProjection(String[] projection) { |
| return projection != null ? projection : DEFAULT_ROOT_PROJECTION; |
| } |
| |
| private static String[] resolveDocumentProjection(String[] projection) { |
| return projection != null ? projection : DEFAULT_DOCUMENT_PROJECTION; |
| } |
| |
| /** |
| * Get a file's MIME type |
| * |
| * @param file the File object whose type we want |
| * @return the MIME type of the file |
| */ |
| private static String getTypeForFile(File file) { |
| if (file.isDirectory()) { |
| return Document.MIME_TYPE_DIR; |
| } else { |
| return getTypeForName(file.getName()); |
| } |
| } |
| |
| /** |
| * Get the MIME data type of a document, given its filename. |
| * |
| * @param name the filename of the document |
| * @return the MIME data type of a document |
| */ |
| private static String getTypeForName(String name) { |
| final int lastDot = name.lastIndexOf('.'); |
| if (lastDot >= 0) { |
| final String extension = name.substring(lastDot + 1); |
| final String mime = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension); |
| if (mime != null) { |
| return mime; |
| } |
| } |
| return "application/octet-stream"; |
| } |
| |
| /** |
| * Gets a string of unique MIME data types a directory supports, separated by newlines. This |
| * should not change. |
| * |
| * @param parent the File for the parent directory |
| * @return a string of the unique MIME data types the parent directory supports |
| */ |
| private String getChildMimeTypes(File parent) { |
| Set<String> mimeTypes = new HashSet<String>(); |
| mimeTypes.add("image/*"); |
| mimeTypes.add("text/*"); |
| mimeTypes.add("application/vnd.openxmlformats-officedocument.wordprocessingml.document"); |
| |
| // Flatten the list into a string and insert newlines between the MIME type strings. |
| StringBuilder mimeTypesString = new StringBuilder(); |
| for (String mimeType : mimeTypes) { |
| mimeTypesString.append(mimeType).append("\n"); |
| } |
| |
| return mimeTypesString.toString(); |
| } |
| |
| /** |
| * Get the document ID given a File. The document id must be consistent across time. Other |
| * applications may save the ID and use it to reference documents later. |
| * <p/> |
| * This implementation is specific to this demo. It assumes only one root and is built |
| * directly from the file structure. However, it is possible for a document to be a child of |
| * multiple directories (for example "android" and "images"), in which case the file must have |
| * the same consistent, unique document ID in both cases. |
| * |
| * @param file the File whose document ID you want |
| * @return the corresponding document ID |
| */ |
| private String getDocIdForFile(File file) { |
| String path = file.getAbsolutePath(); |
| |
| // Start at first char of path under root |
| final String rootPath = mBaseDir.getPath(); |
| if (rootPath.equals(path)) { |
| path = ""; |
| } else if (rootPath.endsWith("/")) { |
| path = path.substring(rootPath.length()); |
| } else { |
| path = path.substring(rootPath.length() + 1); |
| } |
| |
| return "root" + ':' + path; |
| } |
| |
| /** |
| * Add a representation of a file to a cursor. |
| * |
| * @param result the cursor to modify |
| * @param docId the document ID representing the desired file (may be null if given file) |
| * @param file the File object representing the desired file (may be null if given docID) |
| * @throws java.io.FileNotFoundException |
| */ |
| private void includeFile(MatrixCursor result, String docId, File file) |
| throws FileNotFoundException { |
| if (docId == null) { |
| docId = getDocIdForFile(file); |
| } else { |
| file = getFileForDocId(docId); |
| } |
| |
| int flags = 0; |
| |
| if (file.isDirectory()) { |
| // Request the folder to lay out as a grid rather than a list. This also allows a larger |
| // thumbnail to be displayed for each image. |
| // flags |= Document.FLAG_DIR_PREFERS_GRID; |
| |
| // Add FLAG_DIR_SUPPORTS_CREATE if the file is a writable directory. |
| if (file.isDirectory() && file.canWrite()) { |
| flags |= Document.FLAG_DIR_SUPPORTS_CREATE; |
| } |
| } else if (file.canWrite()) { |
| // If the file is writable set FLAG_SUPPORTS_WRITE and |
| // FLAG_SUPPORTS_DELETE |
| flags |= Document.FLAG_SUPPORTS_WRITE; |
| flags |= Document.FLAG_SUPPORTS_DELETE; |
| } |
| |
| final String displayName = file.getName(); |
| final String mimeType = getTypeForFile(file); |
| |
| if (mimeType.startsWith("image/")) { |
| // Allow the image to be represented by a thumbnail rather than an icon |
| flags |= Document.FLAG_SUPPORTS_THUMBNAIL; |
| } |
| |
| final MatrixCursor.RowBuilder row = result.newRow(); |
| row.add(Document.COLUMN_DOCUMENT_ID, docId); |
| row.add(Document.COLUMN_DISPLAY_NAME, displayName); |
| row.add(Document.COLUMN_SIZE, file.length()); |
| row.add(Document.COLUMN_MIME_TYPE, mimeType); |
| row.add(Document.COLUMN_LAST_MODIFIED, file.lastModified()); |
| row.add(Document.COLUMN_FLAGS, flags); |
| |
| // Add a custom icon |
| row.add(Document.COLUMN_ICON, R.drawable.ic_launcher); |
| } |
| |
| /** |
| * Translate your custom URI scheme into a File object. |
| * |
| * @param docId the document ID representing the desired file |
| * @return a File represented by the given document ID |
| * @throws java.io.FileNotFoundException |
| */ |
| private File getFileForDocId(String docId) throws FileNotFoundException { |
| File target = mBaseDir; |
| if (docId.equals(ROOT)) { |
| return target; |
| } |
| final int splitIndex = docId.indexOf(':', 1); |
| if (splitIndex < 0) { |
| throw new FileNotFoundException("Missing root for " + docId); |
| } else { |
| final String path = docId.substring(splitIndex + 1); |
| target = new File(target, path); |
| if (!target.exists()) { |
| throw new FileNotFoundException("Missing file for " + docId + " at " + target); |
| } |
| return target; |
| } |
| } |
| |
| |
| /** |
| * Preload sample files packaged in the apk into the internal storage directory. This is a |
| * dummy function specific to this demo. The MyCloud mock cloud service doesn't actually |
| * have a backend, so it simulates by reading content from the device's internal storage. |
| */ |
| private void writeDummyFilesToStorage() { |
| if (mBaseDir.list().length > 0) { |
| return; |
| } |
| |
| int[] imageResIds = getResourceIdArray(R.array.image_res_ids); |
| for (int resId : imageResIds) { |
| writeFileToInternalStorage(resId, ".jpeg"); |
| } |
| |
| int[] textResIds = getResourceIdArray(R.array.text_res_ids); |
| for (int resId : textResIds) { |
| writeFileToInternalStorage(resId, ".txt"); |
| } |
| |
| int[] docxResIds = getResourceIdArray(R.array.docx_res_ids); |
| for (int resId : docxResIds) { |
| writeFileToInternalStorage(resId, ".docx"); |
| } |
| } |
| |
| /** |
| * Write a file to internal storage. Used to set up our dummy "cloud server". |
| * |
| * @param resId the resource ID of the file to write to internal storage |
| * @param extension the file extension (ex. .png, .mp3) |
| */ |
| private void writeFileToInternalStorage(int resId, String extension) { |
| InputStream ins = getContext().getResources().openRawResource(resId); |
| ByteArrayOutputStream outputStream = new ByteArrayOutputStream(); |
| int size; |
| byte[] buffer = new byte[1024]; |
| try { |
| while ((size = ins.read(buffer, 0, 1024)) >= 0) { |
| outputStream.write(buffer, 0, size); |
| } |
| ins.close(); |
| buffer = outputStream.toByteArray(); |
| String filename = getContext().getResources().getResourceEntryName(resId) + extension; |
| FileOutputStream fos = getContext().openFileOutput(filename, Context.MODE_PRIVATE); |
| fos.write(buffer); |
| fos.close(); |
| |
| } catch (IOException e) { |
| e.printStackTrace(); |
| } |
| } |
| |
| private int[] getResourceIdArray(int arrayResId) { |
| TypedArray ar = getContext().getResources().obtainTypedArray(arrayResId); |
| int len = ar.length(); |
| int[] resIds = new int[len]; |
| for (int i = 0; i < len; i++) { |
| resIds[i] = ar.getResourceId(i, 0); |
| } |
| ar.recycle(); |
| return resIds; |
| } |
| |
| /** |
| * Dummy function to determine whether the user is logged in. |
| */ |
| private boolean isUserLoggedIn() { |
| final SharedPreferences sharedPreferences = |
| getContext().getSharedPreferences(getContext().getString(R.string.app_name), |
| Context.MODE_PRIVATE); |
| return sharedPreferences.getBoolean(getContext().getString(R.string.key_logged_in), false); |
| } |
| |
| |
| } |