src/com/android/documentsui/DirectoryFragment.java

/*
 * 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.android.documentsui;

import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.app.LoaderManager.LoaderCallbacks;
import android.content.Context;
import android.content.Loader;
import android.net.Uri;
import android.os.Bundle;
import android.provider.DocumentsContract;
import android.text.format.DateUtils;
import android.util.SparseBooleanArray;
import android.view.ActionMode;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AbsListView.MultiChoiceModeListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

import com.android.documentsui.DocumentsActivity.DisplayState;
import com.android.documentsui.model.Document;
import com.android.internal.util.Predicate;
import com.google.android.collect.Lists;

import java.util.ArrayList;
import java.util.Comparator;
import java.util.List;

/**
 * Display the documents inside a single directory.
 */
public class DirectoryFragment extends Fragment {

    // TODO: show storage backend in item views when requested

    private ListView mListView;
    private GridView mGridView;

    private AbsListView mCurrentView;

    public static final int TYPE_NORMAL = 1;
    public static final int TYPE_SEARCH = 2;
    public static final int TYPE_RECENT_OPEN = 3;
    public static final int TYPE_RECENT_CREATE = 4;

    private int mType = TYPE_NORMAL;

    private DocumentsAdapter mAdapter;
    private LoaderCallbacks<List<Document>> mCallbacks;

    private static final String EXTRA_URI = "uri";

    private static final int LOADER_DOCUMENTS = 2;

    public static void show(FragmentManager fm, Uri uri) {
        final Bundle args = new Bundle();
        args.putParcelable(EXTRA_URI, uri);

        final DirectoryFragment fragment = new DirectoryFragment();
        fragment.setArguments(args);

        final FragmentTransaction ft = fm.beginTransaction();
        ft.replace(R.id.directory, fragment);
        ft.commitAllowingStateLoss();
    }

    public static DirectoryFragment get(FragmentManager fm) {
        // TODO: deal with multiple directories shown at once
        return (DirectoryFragment) fm.findFragmentById(R.id.directory);
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setHasOptionsMenu(true);
    }

    @Override
    public View onCreateView(
            LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        final Context context = inflater.getContext();

        final View view = inflater.inflate(R.layout.fragment_directory, container, false);

        mListView = (ListView) view.findViewById(R.id.list);
        mListView.setOnItemClickListener(mItemListener);
        mListView.setMultiChoiceModeListener(mMultiListener);

        mGridView = (GridView) view.findViewById(R.id.grid);
        mGridView.setOnItemClickListener(mItemListener);
        mGridView.setMultiChoiceModeListener(mMultiListener);

        mAdapter = new DocumentsAdapter();
        updateMode();

        final Uri uri = getArguments().getParcelable(EXTRA_URI);

        if (uri.getQueryParameter(DocumentsContract.PARAM_QUERY) != null) {
            mType = TYPE_SEARCH;
        } else if (RecentsProvider.buildRecentOpen().equals(uri)) {
            mType = TYPE_RECENT_OPEN;
        } else if (RecentsProvider.buildRecentCreate().equals(uri)) {
            mType = TYPE_RECENT_CREATE;
        } else {
            mType = TYPE_NORMAL;
        }

        mCallbacks = new LoaderCallbacks<List<Document>>() {
            @Override
            public Loader<List<Document>> onCreateLoader(int id, Bundle args) {
                final DisplayState state = getDisplayState(DirectoryFragment.this);

                final Uri contentsUri;
                if (mType == TYPE_NORMAL) {
                    contentsUri = DocumentsContract.buildContentsUri(uri);
                } else {
                    contentsUri = uri;
                }

                final Predicate<Document> filter = new MimePredicate(state.acceptMimes);

                final Comparator<Document> sortOrder;
                if (state.sortOrder == DisplayState.SORT_ORDER_DATE || mType == TYPE_RECENT_OPEN
                        || mType == TYPE_RECENT_CREATE) {
                    sortOrder = new Document.DateComparator();
                } else if (state.sortOrder == DisplayState.SORT_ORDER_NAME) {
                    sortOrder = new Document.NameComparator();
                } else {
                    throw new IllegalArgumentException("Unknown sort order " + state.sortOrder);
                }

                return new DirectoryLoader(context, contentsUri, mType, filter, sortOrder);
            }

            @Override
            public void onLoadFinished(Loader<List<Document>> loader, List<Document> data) {
                mAdapter.swapDocuments(data);
            }

            @Override
            public void onLoaderReset(Loader<List<Document>> loader) {
                mAdapter.swapDocuments(null);
            }
        };

        return view;
    }

    @Override
    public void onStart() {
        super.onStart();
        getLoaderManager().restartLoader(LOADER_DOCUMENTS, getArguments(), mCallbacks);
    }

    @Override
    public void onStop() {
        super.onStop();
        getLoaderManager().destroyLoader(LOADER_DOCUMENTS);
    }

    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        super.onCreateOptionsMenu(menu, inflater);
        inflater.inflate(R.menu.directory, menu);
    }

    @Override
    public void onPrepareOptionsMenu(Menu menu) {
        super.onPrepareOptionsMenu(menu);
        final DisplayState state = getDisplayState(this);
        menu.findItem(R.id.menu_grid).setVisible(state.mode != DisplayState.MODE_GRID);
        menu.findItem(R.id.menu_list).setVisible(state.mode != DisplayState.MODE_LIST);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        final DisplayState state = getDisplayState(this);
        final int id = item.getItemId();
        if (id == R.id.menu_grid) {
            state.mode = DisplayState.MODE_GRID;
            updateMode();
            getFragmentManager().invalidateOptionsMenu();
            return true;
        } else if (id == R.id.menu_list) {
            state.mode = DisplayState.MODE_LIST;
            updateMode();
            getFragmentManager().invalidateOptionsMenu();
            return true;
        } else {
            return super.onOptionsItemSelected(item);
        }
    }

    private void updateMode() {
        final DisplayState state = getDisplayState(this);

        mListView.setVisibility(state.mode == DisplayState.MODE_LIST ? View.VISIBLE : View.GONE);
        mGridView.setVisibility(state.mode == DisplayState.MODE_GRID ? View.VISIBLE : View.GONE);

        final int choiceMode;
        if (state.allowMultiple) {
            choiceMode = ListView.CHOICE_MODE_MULTIPLE_MODAL;
        } else {
            choiceMode = ListView.CHOICE_MODE_NONE;
        }

        if (state.mode == DisplayState.MODE_GRID) {
            mListView.setAdapter(null);
            mListView.setChoiceMode(ListView.CHOICE_MODE_NONE);
            mGridView.setAdapter(mAdapter);
            mGridView.setColumnWidth(getResources().getDimensionPixelSize(R.dimen.grid_width));
            mGridView.setNumColumns(GridView.AUTO_FIT);
            mGridView.setChoiceMode(choiceMode);
            mCurrentView = mGridView;
        } else if (state.mode == DisplayState.MODE_LIST) {
            mGridView.setAdapter(null);
            mGridView.setChoiceMode(ListView.CHOICE_MODE_NONE);
            mListView.setAdapter(mAdapter);
            mListView.setChoiceMode(choiceMode);
            mCurrentView = mListView;
        } else {
            throw new IllegalStateException();
        }
    }

    public void updateSortOrder() {
        getLoaderManager().restartLoader(LOADER_DOCUMENTS, getArguments(), mCallbacks);
        mListView.smoothScrollToPosition(0);
        mGridView.smoothScrollToPosition(0);
    }

    private OnItemClickListener mItemListener = new OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            final Document doc = mAdapter.getItem(position);
            ((DocumentsActivity) getActivity()).onDocumentPicked(doc);
        }
    };

    private MultiChoiceModeListener mMultiListener = new MultiChoiceModeListener() {
        @Override
        public boolean onCreateActionMode(ActionMode mode, Menu menu) {
            mode.getMenuInflater().inflate(R.menu.mode_directory, menu);
            return true;
        }

        @Override
        public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
            return true;
        }

        @Override
        public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
            if (item.getItemId() == R.id.menu_open) {
                final Uri uri = getArguments().getParcelable(EXTRA_URI);
                final SparseBooleanArray checked = mCurrentView.getCheckedItemPositions();
                final ArrayList<Document> docs = Lists.newArrayList();

                final int size = checked.size();
                for (int i = 0; i < size; i++) {
                    if (checked.valueAt(i)) {
                        final Document doc = mAdapter.getItem(checked.keyAt(i));
                        docs.add(doc);
                    }
                }

                ((DocumentsActivity) getActivity()).onDocumentsPicked(docs);
                return true;
            } else {
                return false;
            }
        }

        @Override
        public void onDestroyActionMode(ActionMode mode) {
            // ignored
        }

        @Override
        public void onItemCheckedStateChanged(
                ActionMode mode, int position, long id, boolean checked) {
            if (checked) {
                // Directories cannot be checked
                final Document doc = mAdapter.getItem(position);
                if (DocumentsContract.MIME_TYPE_DIRECTORY.equals(doc.mimeType)) {
                    mCurrentView.setItemChecked(position, false);
                }
            }

            mode.setTitle(getResources()
                    .getString(R.string.mode_selected_count, mCurrentView.getCheckedItemCount()));
        }
    };

    private static DisplayState getDisplayState(Fragment fragment) {
        return ((DocumentsActivity) fragment.getActivity()).getDisplayState();
    }

    private class DocumentsAdapter extends BaseAdapter {
        private List<Document> mDocuments;

        public DocumentsAdapter() {
        }

        public void swapDocuments(List<Document> documents) {
            mDocuments = documents;
            notifyDataSetChanged();
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            final Context context = parent.getContext();

            if (convertView == null) {
                final LayoutInflater inflater = LayoutInflater.from(context);
                final DisplayState state = getDisplayState(DirectoryFragment.this);
                if (state.mode == DisplayState.MODE_LIST) {
                    convertView = inflater.inflate(R.layout.item_doc_list, parent, false);
                } else if (state.mode == DisplayState.MODE_GRID) {
                    convertView = inflater.inflate(R.layout.item_doc_grid, parent, false);
                } else {
                    throw new IllegalStateException();
                }
            }

            final Document doc = getItem(position);

            final TextView title = (TextView) convertView.findViewById(android.R.id.title);
            final TextView summary = (TextView) convertView.findViewById(android.R.id.summary);
            final ImageView icon = (ImageView) convertView.findViewById(android.R.id.icon);

            if (doc.isThumbnailSupported()) {
                // TODO: load thumbnails async
                icon.setImageURI(doc.uri);
            } else {
                icon.setImageDrawable(DocumentsActivity.resolveDocumentIcon(
                        context, doc.uri.getAuthority(), doc.mimeType));
            }

            title.setText(doc.displayName);
            if (summary != null) {
                summary.setText(DateUtils.getRelativeTimeSpanString(doc.lastModified));
            }

            return convertView;
        }

        @Override
        public int getCount() {
            return mDocuments != null ? mDocuments.size() : 0;
        }

        @Override
        public Document getItem(int position) {
            return mDocuments.get(position);
        }

        @Override
        public long getItemId(int position) {
            return getItem(position).uri.hashCode();
        }
    }
}