DirectoryFragment.java revision d182bb641f228b2d28527a6aa86075f6358ab838 
1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.documentsui;
18
19import static com.android.documentsui.DocumentsActivity.TAG;
20import static com.android.documentsui.DocumentsActivity.State.ACTION_MANAGE;
21import static com.android.documentsui.DocumentsActivity.State.MODE_GRID;
22import static com.android.documentsui.DocumentsActivity.State.MODE_LIST;
23import static com.android.documentsui.DocumentsActivity.State.MODE_UNKNOWN;
24import static com.android.documentsui.DocumentsActivity.State.SORT_ORDER_UNKNOWN;
25import static com.android.documentsui.model.DocumentInfo.getCursorInt;
26import static com.android.documentsui.model.DocumentInfo.getCursorLong;
27import static com.android.documentsui.model.DocumentInfo.getCursorString;
28
29import android.app.Fragment;
30import android.app.FragmentManager;
31import android.app.FragmentTransaction;
32import android.app.LoaderManager.LoaderCallbacks;
33import android.content.ContentResolver;
34import android.content.Context;
35import android.content.Intent;
36import android.content.Loader;
37import android.database.Cursor;
38import android.graphics.Bitmap;
39import android.graphics.Point;
40import android.net.Uri;
41import android.os.AsyncTask;
42import android.os.Bundle;
43import android.provider.DocumentsContract;
44import android.provider.DocumentsContract.Document;
45import android.text.format.DateUtils;
46import android.text.format.Formatter;
47import android.text.format.Time;
48import android.util.Log;
49import android.util.SparseBooleanArray;
50import android.view.ActionMode;
51import android.view.LayoutInflater;
52import android.view.Menu;
53import android.view.MenuItem;
54import android.view.View;
55import android.view.ViewGroup;
56import android.widget.AbsListView;
57import android.widget.AbsListView.MultiChoiceModeListener;
58import android.widget.AdapterView;
59import android.widget.AdapterView.OnItemClickListener;
60import android.widget.BaseAdapter;
61import android.widget.GridView;
62import android.widget.ImageView;
63import android.widget.ListView;
64import android.widget.TextView;
65import android.widget.Toast;
66
67import com.android.documentsui.DocumentsActivity.State;
68import com.android.documentsui.model.DocumentInfo;
69import com.android.documentsui.model.RootInfo;
70import com.android.internal.util.Predicate;
71import com.google.android.collect.Lists;
72
73import java.util.ArrayList;
74import java.util.List;
75import java.util.concurrent.atomic.AtomicInteger;
76
77/**
78 * Display the documents inside a single directory.
79 */
80public class DirectoryFragment extends Fragment {
81
82    private View mEmptyView;
83    private ListView mListView;
84    private GridView mGridView;
85
86    private AbsListView mCurrentView;
87
88    private Predicate<DocumentInfo> mFilter;
89
90    public static final int TYPE_NORMAL = 1;
91    public static final int TYPE_SEARCH = 2;
92    public static final int TYPE_RECENT_OPEN = 3;
93
94    private int mType = TYPE_NORMAL;
95
96    private int mLastMode = MODE_UNKNOWN;
97    private int mLastSortOrder = SORT_ORDER_UNKNOWN;
98
99    private Point mThumbSize;
100
101    private DocumentsAdapter mAdapter;
102    private LoaderCallbacks<DirectoryResult> mCallbacks;
103
104    private static final String EXTRA_TYPE = "type";
105    private static final String EXTRA_ROOT = "root";
106    private static final String EXTRA_DOC = "doc";
107    private static final String EXTRA_QUERY = "query";
108
109    private static AtomicInteger sLoaderId = new AtomicInteger(4000);
110
111    private final int mLoaderId = sLoaderId.incrementAndGet();
112
113    public static void showNormal(FragmentManager fm, RootInfo root, DocumentInfo doc) {
114        show(fm, TYPE_NORMAL, root, doc, null);
115    }
116
117    public static void showSearch(
118            FragmentManager fm, RootInfo root, DocumentInfo doc, String query) {
119        show(fm, TYPE_SEARCH, root, doc, query);
120    }
121
122    public static void showRecentsOpen(FragmentManager fm) {
123        show(fm, TYPE_RECENT_OPEN, null, null, null);
124    }
125
126    private static void show(
127            FragmentManager fm, int type, RootInfo root, DocumentInfo doc, String query) {
128        final Bundle args = new Bundle();
129        args.putInt(EXTRA_TYPE, type);
130        args.putParcelable(EXTRA_ROOT, root);
131        args.putParcelable(EXTRA_DOC, doc);
132        args.putString(EXTRA_QUERY, query);
133
134        final DirectoryFragment fragment = new DirectoryFragment();
135        fragment.setArguments(args);
136
137        final FragmentTransaction ft = fm.beginTransaction();
138        ft.replace(R.id.container_directory, fragment);
139        ft.commitAllowingStateLoss();
140    }
141
142    public static DirectoryFragment get(FragmentManager fm) {
143        // TODO: deal with multiple directories shown at once
144        return (DirectoryFragment) fm.findFragmentById(R.id.container_directory);
145    }
146
147    @Override
148    public View onCreateView(
149            LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
150        final Context context = inflater.getContext();
151        final View view = inflater.inflate(R.layout.fragment_directory, container, false);
152
153        mEmptyView = view.findViewById(android.R.id.empty);
154
155        mListView = (ListView) view.findViewById(R.id.list);
156        mListView.setOnItemClickListener(mItemListener);
157        mListView.setMultiChoiceModeListener(mMultiListener);
158
159        mGridView = (GridView) view.findViewById(R.id.grid);
160        mGridView.setOnItemClickListener(mItemListener);
161        mGridView.setMultiChoiceModeListener(mMultiListener);
162
163        return view;
164    }
165
166    @Override
167    public void onActivityCreated(Bundle savedInstanceState) {
168        super.onActivityCreated(savedInstanceState);
169
170        final Context context = getActivity();
171        final State state = getDisplayState(DirectoryFragment.this);
172
173        mAdapter = new DocumentsAdapter();
174        mType = getArguments().getInt(EXTRA_TYPE);
175
176        mCallbacks = new LoaderCallbacks<DirectoryResult>() {
177            @Override
178            public Loader<DirectoryResult> onCreateLoader(int id, Bundle args) {
179                final RootInfo root = getArguments().getParcelable(EXTRA_ROOT);
180                final DocumentInfo doc = getArguments().getParcelable(EXTRA_DOC);
181                final String query = getArguments().getString(EXTRA_QUERY);
182
183                Uri contentsUri;
184                switch (mType) {
185                    case TYPE_NORMAL:
186                        contentsUri = DocumentsContract.buildChildDocumentsUri(
187                                doc.authority, doc.documentId);
188                        return new DirectoryLoader(context, root, doc, contentsUri);
189                    case TYPE_SEARCH:
190                        contentsUri = DocumentsContract.buildSearchDocumentsUri(
191                                doc.authority, doc.documentId, query);
192                        return new DirectoryLoader(context, root, doc, contentsUri);
193                    case TYPE_RECENT_OPEN:
194                        final RootsCache roots = DocumentsApplication.getRootsCache(context);
195                        final List<RootInfo> matchingRoots = roots.getMatchingRoots(state);
196                        return new RecentLoader(context, matchingRoots, state.acceptMimes);
197                    default:
198                        throw new IllegalStateException("Unknown type " + mType);
199                }
200            }
201
202            @Override
203            public void onLoadFinished(Loader<DirectoryResult> loader, DirectoryResult result) {
204                if (!isAdded()) return;
205
206                mAdapter.swapCursor(result.cursor);
207
208                // Push latest state up to UI
209                // TODO: if mode change was racing with us, don't overwrite it
210                state.mode = result.mode;
211                state.sortOrder = result.sortOrder;
212                ((DocumentsActivity) context).onStateChanged();
213
214                updateDisplayState();
215
216                if (mLastSortOrder != result.sortOrder) {
217                    mLastSortOrder = result.sortOrder;
218                    mListView.smoothScrollToPosition(0);
219                    mGridView.smoothScrollToPosition(0);
220                }
221            }
222
223            @Override
224            public void onLoaderReset(Loader<DirectoryResult> loader) {
225                mAdapter.swapCursor(null);
226            }
227        };
228
229        // Kick off loader at least once
230        getLoaderManager().restartLoader(mLoaderId, null, mCallbacks);
231
232        updateDisplayState();
233    }
234
235    @Override
236    public void onStart() {
237        super.onStart();
238        updateDisplayState();
239    }
240
241    public void onUserSortOrderChanged() {
242        // User change always triggers reload
243        getLoaderManager().restartLoader(mLoaderId, null, mCallbacks);
244    }
245
246    public void onUserModeChanged() {
247        // Mode change is just display; no need to reload
248        updateDisplayState();
249    }
250
251    private void updateDisplayState() {
252        final State state = getDisplayState(this);
253
254        mFilter = new MimePredicate(state.acceptMimes);
255
256        if (mLastMode == state.mode) return;
257        mLastMode = state.mode;
258
259        mListView.setVisibility(state.mode == MODE_LIST ? View.VISIBLE : View.GONE);
260        mGridView.setVisibility(state.mode == MODE_GRID ? View.VISIBLE : View.GONE);
261
262        final int choiceMode;
263        if (state.allowMultiple) {
264            choiceMode = ListView.CHOICE_MODE_MULTIPLE_MODAL;
265        } else {
266            choiceMode = ListView.CHOICE_MODE_NONE;
267        }
268
269        final int thumbSize;
270        if (state.mode == MODE_GRID) {
271            thumbSize = getResources().getDimensionPixelSize(R.dimen.grid_width);
272            mListView.setAdapter(null);
273            mListView.setChoiceMode(ListView.CHOICE_MODE_NONE);
274            mGridView.setAdapter(mAdapter);
275            mGridView.setColumnWidth(getResources().getDimensionPixelSize(R.dimen.grid_width));
276            mGridView.setNumColumns(GridView.AUTO_FIT);
277            mGridView.setChoiceMode(choiceMode);
278            mCurrentView = mGridView;
279        } else if (state.mode == MODE_LIST) {
280            thumbSize = getResources().getDimensionPixelSize(R.dimen.icon_size);
281            mGridView.setAdapter(null);
282            mGridView.setChoiceMode(ListView.CHOICE_MODE_NONE);
283            mListView.setAdapter(mAdapter);
284            mListView.setChoiceMode(choiceMode);
285            mCurrentView = mListView;
286        } else {
287            throw new IllegalStateException("Unknown state " + state.mode);
288        }
289
290        mThumbSize = new Point(thumbSize, thumbSize);
291    }
292
293    private OnItemClickListener mItemListener = new OnItemClickListener() {
294        @Override
295        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
296            final Cursor cursor = mAdapter.getItem(position);
297            final DocumentInfo doc = DocumentInfo.fromDirectoryCursor(cursor);
298            if (mFilter.apply(doc)) {
299                ((DocumentsActivity) getActivity()).onDocumentPicked(doc);
300            }
301        }
302    };
303
304    private MultiChoiceModeListener mMultiListener = new MultiChoiceModeListener() {
305        @Override
306        public boolean onCreateActionMode(ActionMode mode, Menu menu) {
307            mode.getMenuInflater().inflate(R.menu.mode_directory, menu);
308            return true;
309        }
310
311        @Override
312        public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
313            final State state = getDisplayState(DirectoryFragment.this);
314
315            final MenuItem open = menu.findItem(R.id.menu_open);
316            final MenuItem share = menu.findItem(R.id.menu_share);
317            final MenuItem delete = menu.findItem(R.id.menu_delete);
318
319            final boolean manageMode = state.action == ACTION_MANAGE;
320            open.setVisible(!manageMode);
321            share.setVisible(manageMode);
322            delete.setVisible(manageMode);
323
324            return true;
325        }
326
327        @Override
328        public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
329            final SparseBooleanArray checked = mCurrentView.getCheckedItemPositions();
330            final ArrayList<DocumentInfo> docs = Lists.newArrayList();
331            final int size = checked.size();
332            for (int i = 0; i < size; i++) {
333                if (checked.valueAt(i)) {
334                    final Cursor cursor = mAdapter.getItem(checked.keyAt(i));
335                    final DocumentInfo doc = DocumentInfo.fromDirectoryCursor(cursor);
336                    docs.add(doc);
337                }
338            }
339
340            final int id = item.getItemId();
341            if (id == R.id.menu_open) {
342                DocumentsActivity.get(DirectoryFragment.this).onDocumentsPicked(docs);
343                mode.finish();
344                return true;
345
346            } else if (id == R.id.menu_share) {
347                onShareDocuments(docs);
348                mode.finish();
349                return true;
350
351            } else if (id == R.id.menu_delete) {
352                onDeleteDocuments(docs);
353                mode.finish();
354                return true;
355
356            } else {
357                return false;
358            }
359        }
360
361        @Override
362        public void onDestroyActionMode(ActionMode mode) {
363            // ignored
364        }
365
366        @Override
367        public void onItemCheckedStateChanged(
368                ActionMode mode, int position, long id, boolean checked) {
369            if (checked) {
370                // Directories cannot be checked
371                final Cursor cursor = mAdapter.getItem(position);
372                final String docMimeType = getCursorString(cursor, Document.COLUMN_MIME_TYPE);
373                if (Document.MIME_TYPE_DIR.equals(docMimeType)) {
374                    mCurrentView.setItemChecked(position, false);
375                }
376            }
377
378            mode.setTitle(getResources()
379                    .getString(R.string.mode_selected_count, mCurrentView.getCheckedItemCount()));
380        }
381    };
382
383    private void onShareDocuments(List<DocumentInfo> docs) {
384        Intent intent;
385        if (docs.size() == 1) {
386            final DocumentInfo doc = docs.get(0);
387
388            intent = new Intent(Intent.ACTION_SEND);
389            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
390            intent.addCategory(Intent.CATEGORY_DEFAULT);
391            intent.setType(doc.mimeType);
392            intent.putExtra(Intent.EXTRA_STREAM, doc.derivedUri);
393
394        } else if (docs.size() > 1) {
395            intent = new Intent(Intent.ACTION_SEND_MULTIPLE);
396            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
397            intent.addCategory(Intent.CATEGORY_DEFAULT);
398
399            final ArrayList<String> mimeTypes = Lists.newArrayList();
400            final ArrayList<Uri> uris = Lists.newArrayList();
401            for (DocumentInfo doc : docs) {
402                mimeTypes.add(doc.mimeType);
403                uris.add(doc.derivedUri);
404            }
405
406            intent.setType(findCommonMimeType(mimeTypes));
407            intent.putParcelableArrayListExtra(Intent.EXTRA_STREAM, uris);
408
409        } else {
410            return;
411        }
412
413        intent = Intent.createChooser(intent, getActivity().getText(R.string.share_via));
414        startActivity(intent);
415    }
416
417    private void onDeleteDocuments(List<DocumentInfo> docs) {
418        final Context context = getActivity();
419        final ContentResolver resolver = context.getContentResolver();
420
421        boolean hadTrouble = false;
422        for (DocumentInfo doc : docs) {
423            if (!doc.isDeleteSupported()) {
424                Log.w(TAG, "Skipping " + doc);
425                hadTrouble = true;
426                continue;
427            }
428
429            if (!DocumentsContract.deleteDocument(resolver, doc.derivedUri)) {
430                Log.w(TAG, "Failed to delete " + doc);
431                hadTrouble = true;
432            }
433        }
434
435        if (hadTrouble) {
436            Toast.makeText(context, R.string.toast_failed_delete, Toast.LENGTH_SHORT).show();
437        }
438    }
439
440    private static State getDisplayState(Fragment fragment) {
441        return ((DocumentsActivity) fragment.getActivity()).getDisplayState();
442    }
443
444    private interface Footer {
445        public View getView(View convertView, ViewGroup parent);
446    }
447
448    private static class LoadingFooter implements Footer {
449        @Override
450        public View getView(View convertView, ViewGroup parent) {
451            final Context context = parent.getContext();
452            if (convertView == null) {
453                final LayoutInflater inflater = LayoutInflater.from(context);
454                convertView = inflater.inflate(R.layout.item_loading, parent, false);
455            }
456            return convertView;
457        }
458    }
459
460    private class MessageFooter implements Footer {
461        private final int mIcon;
462        private final String mMessage;
463
464        public MessageFooter(int icon, String message) {
465            mIcon = icon;
466            mMessage = message;
467        }
468
469        @Override
470        public View getView(View convertView, ViewGroup parent) {
471            final Context context = parent.getContext();
472            final State state = getDisplayState(DirectoryFragment.this);
473
474            if (convertView == null) {
475                final LayoutInflater inflater = LayoutInflater.from(context);
476                if (state.mode == MODE_LIST) {
477                    convertView = inflater.inflate(R.layout.item_message_list, parent, false);
478                } else if (state.mode == MODE_GRID) {
479                    convertView = inflater.inflate(R.layout.item_message_grid, parent, false);
480                } else {
481                    throw new IllegalStateException();
482                }
483            }
484
485            final ImageView icon = (ImageView) convertView.findViewById(android.R.id.icon);
486            final TextView title = (TextView) convertView.findViewById(android.R.id.title);
487            icon.setImageResource(mIcon);
488            title.setText(mMessage);
489            return convertView;
490        }
491    }
492
493    private class DocumentsAdapter extends BaseAdapter {
494        private Cursor mCursor;
495        private int mCursorCount;
496
497        private List<Footer> mFooters = Lists.newArrayList();
498
499        public void swapCursor(Cursor cursor) {
500            mCursor = cursor;
501            mCursorCount = cursor != null ? cursor.getCount() : 0;
502
503            mFooters.clear();
504
505            final Bundle extras = cursor != null ? cursor.getExtras() : null;
506            if (extras != null) {
507                final String info = extras.getString(DocumentsContract.EXTRA_INFO);
508                if (info != null) {
509                    mFooters.add(new MessageFooter(R.drawable.ic_dialog_alert, info));
510                }
511                final String error = extras.getString(DocumentsContract.EXTRA_ERROR);
512                if (error != null) {
513                    mFooters.add(new MessageFooter(R.drawable.ic_dialog_alert, error));
514                }
515                if (extras.getBoolean(DocumentsContract.EXTRA_LOADING, false)) {
516                    mFooters.add(new LoadingFooter());
517                }
518            }
519
520            if (isEmpty()) {
521                mEmptyView.setVisibility(View.VISIBLE);
522            } else {
523                mEmptyView.setVisibility(View.GONE);
524            }
525
526            notifyDataSetChanged();
527        }
528
529        @Override
530        public View getView(int position, View convertView, ViewGroup parent) {
531            if (position < mCursorCount) {
532                return getDocumentView(position, convertView, parent);
533            } else {
534                position -= mCursorCount;
535                return mFooters.get(position).getView(convertView, parent);
536            }
537        }
538
539        private View getDocumentView(int position, View convertView, ViewGroup parent) {
540            final Context context = parent.getContext();
541            final State state = getDisplayState(DirectoryFragment.this);
542
543            final RootsCache roots = DocumentsApplication.getRootsCache(context);
544            final ThumbnailCache thumbs = DocumentsApplication.getThumbnailsCache(
545                    context, mThumbSize);
546
547            if (convertView == null) {
548                final LayoutInflater inflater = LayoutInflater.from(context);
549                if (state.mode == MODE_LIST) {
550                    convertView = inflater.inflate(R.layout.item_doc_list, parent, false);
551                } else if (state.mode == MODE_GRID) {
552                    convertView = inflater.inflate(R.layout.item_doc_grid, parent, false);
553                } else {
554                    throw new IllegalStateException();
555                }
556            }
557
558            final Cursor cursor = getItem(position);
559
560            final String docAuthority = getCursorString(cursor, RootCursorWrapper.COLUMN_AUTHORITY);
561            final String docRootId = getCursorString(cursor, RootCursorWrapper.COLUMN_ROOT_ID);
562            final String docId = getCursorString(cursor, Document.COLUMN_DOCUMENT_ID);
563            final String docMimeType = getCursorString(cursor, Document.COLUMN_MIME_TYPE);
564            final String docDisplayName = getCursorString(cursor, Document.COLUMN_DISPLAY_NAME);
565            final long docLastModified = getCursorLong(cursor, Document.COLUMN_LAST_MODIFIED);
566            final int docIcon = getCursorInt(cursor, Document.COLUMN_ICON);
567            final int docFlags = getCursorInt(cursor, Document.COLUMN_FLAGS);
568            final String docSummary = getCursorString(cursor, Document.COLUMN_SUMMARY);
569            final long docSize = getCursorLong(cursor, Document.COLUMN_SIZE);
570
571            final ImageView icon = (ImageView) convertView.findViewById(android.R.id.icon);
572            final TextView title = (TextView) convertView.findViewById(android.R.id.title);
573            final View line2 = convertView.findViewById(R.id.line2);
574            final ImageView icon1 = (ImageView) convertView.findViewById(android.R.id.icon1);
575            final TextView summary = (TextView) convertView.findViewById(android.R.id.summary);
576            final TextView date = (TextView) convertView.findViewById(R.id.date);
577            final TextView size = (TextView) convertView.findViewById(R.id.size);
578
579            final ThumbnailAsyncTask oldTask = (ThumbnailAsyncTask) icon.getTag();
580            if (oldTask != null) {
581                oldTask.cancel(false);
582            }
583
584            if ((docFlags & Document.FLAG_SUPPORTS_THUMBNAIL) != 0) {
585                final Uri uri = DocumentsContract.buildDocumentUri(docAuthority, docId);
586                final Bitmap cachedResult = thumbs.get(uri);
587                if (cachedResult != null) {
588                    icon.setImageBitmap(cachedResult);
589                } else {
590                    final ThumbnailAsyncTask task = new ThumbnailAsyncTask(icon, mThumbSize);
591                    icon.setImageBitmap(null);
592                    icon.setTag(task);
593                    task.execute(uri);
594                }
595            } else if (docIcon != 0) {
596                icon.setImageDrawable(IconUtils.loadPackageIcon(context, docAuthority, docIcon));
597            } else {
598                icon.setImageDrawable(IconUtils.loadMimeIcon(context, docMimeType));
599            }
600
601            title.setText(docDisplayName);
602
603            boolean hasLine2 = false;
604
605            if (mType == TYPE_RECENT_OPEN) {
606                final RootInfo root = roots.getRoot(docAuthority, docRootId);
607                icon1.setVisibility(View.VISIBLE);
608                icon1.setImageDrawable(root.loadIcon(context));
609                summary.setText(root.getDirectoryString());
610                summary.setVisibility(View.VISIBLE);
611                summary.setTextAlignment(TextView.TEXT_ALIGNMENT_TEXT_END);
612                hasLine2 = true;
613            } else {
614                icon1.setVisibility(View.GONE);
615                if (docSummary != null) {
616                    summary.setText(docSummary);
617                    summary.setVisibility(View.VISIBLE);
618                    hasLine2 = true;
619                } else {
620                    summary.setVisibility(View.INVISIBLE);
621                }
622            }
623
624            if (docLastModified == -1) {
625                date.setText(null);
626            } else {
627                date.setText(formatTime(context, docLastModified));
628                hasLine2 = true;
629            }
630
631            if (state.showSize) {
632                size.setVisibility(View.VISIBLE);
633                if (Document.MIME_TYPE_DIR.equals(docMimeType) || docSize == -1) {
634                    size.setText(null);
635                } else {
636                    size.setText(Formatter.formatFileSize(context, docSize));
637                    hasLine2 = true;
638                }
639            } else {
640                size.setVisibility(View.GONE);
641            }
642
643            line2.setVisibility(hasLine2 ? View.VISIBLE : View.GONE);
644
645            return convertView;
646        }
647
648        @Override
649        public int getCount() {
650            return mCursorCount + mFooters.size();
651        }
652
653        @Override
654        public Cursor getItem(int position) {
655            if (position < mCursorCount) {
656                mCursor.moveToPosition(position);
657                return mCursor;
658            } else {
659                return null;
660            }
661        }
662
663        @Override
664        public long getItemId(int position) {
665            return position;
666        }
667
668        @Override
669        public int getItemViewType(int position) {
670            if (position < mCursorCount) {
671                return 0;
672            } else {
673                return IGNORE_ITEM_VIEW_TYPE;
674            }
675        }
676
677        @Override
678        public boolean areAllItemsEnabled() {
679            return false;
680        }
681
682        @Override
683        public boolean isEnabled(int position) {
684            return position < mCursorCount;
685        }
686    }
687
688    private static class ThumbnailAsyncTask extends AsyncTask<Uri, Void, Bitmap> {
689        private final ImageView mTarget;
690        private final Point mThumbSize;
691
692        public ThumbnailAsyncTask(ImageView target, Point thumbSize) {
693            mTarget = target;
694            mThumbSize = thumbSize;
695        }
696
697        @Override
698        protected void onPreExecute() {
699            mTarget.setTag(this);
700        }
701
702        @Override
703        protected Bitmap doInBackground(Uri... params) {
704            final Context context = mTarget.getContext();
705            final Uri uri = params[0];
706
707            Bitmap result = null;
708            try {
709                result = DocumentsContract.getDocumentThumbnail(
710                        context.getContentResolver(), uri, mThumbSize, null);
711                if (result != null) {
712                    final ThumbnailCache thumbs = DocumentsApplication.getThumbnailsCache(
713                            context, mThumbSize);
714                    thumbs.put(uri, result);
715                }
716            } catch (Exception e) {
717                Log.w(TAG, "Failed to load thumbnail: " + e);
718            }
719            return result;
720        }
721
722        @Override
723        protected void onPostExecute(Bitmap result) {
724            if (mTarget.getTag() == this) {
725                mTarget.setImageBitmap(result);
726                mTarget.setTag(null);
727            }
728        }
729    }
730
731    private static String formatTime(Context context, long when) {
732        // TODO: DateUtils should make this easier
733        Time then = new Time();
734        then.set(when);
735        Time now = new Time();
736        now.setToNow();
737
738        int flags = DateUtils.FORMAT_NO_NOON | DateUtils.FORMAT_NO_MIDNIGHT
739                | DateUtils.FORMAT_ABBREV_ALL;
740
741        if (then.year != now.year) {
742            flags |= DateUtils.FORMAT_SHOW_YEAR | DateUtils.FORMAT_SHOW_DATE;
743        } else if (then.yearDay != now.yearDay) {
744            flags |= DateUtils.FORMAT_SHOW_DATE;
745        } else {
746            flags |= DateUtils.FORMAT_SHOW_TIME;
747        }
748
749        return DateUtils.formatDateTime(context, when, flags);
750    }
751
752    private String findCommonMimeType(List<String> mimeTypes) {
753        String[] commonType = mimeTypes.get(0).split("/");
754        if (commonType.length != 2) {
755            return "*/*";
756        }
757
758        for (int i = 1; i < mimeTypes.size(); i++) {
759            String[] type = mimeTypes.get(i).split("/");
760            if (type.length != 2) continue;
761
762            if (!commonType[1].equals(type[1])) {
763                commonType[1] = "*";
764            }
765
766            if (!commonType[0].equals(type[0])) {
767                commonType[0] = "*";
768                commonType[1] = "*";
769                break;
770            }
771        }
772
773        return commonType[0] + "/" + commonType[1];
774    }
775}
776