src/com/owncloud/android/ui/preview/PreviewImagePagerAdapter.java

   1 /**
   2  *   ownCloud Android client application
   3  *
   4  *   @author David A. Velasco
   5  *   Copyright (C) 2015  ownCloud Inc.
   6  *
   7  *   This program is free software: you can redistribute it and/or modify
   8  *   it under the terms of the GNU General Public License version 2,
   9  *   as published by the Free Software Foundation.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  *
  19  */
  20 package com.owncloud.android.ui.preview;
  21
  22 import java.util.HashMap;
  23 import java.util.HashSet;
  24 import java.util.Iterator;
  25 import java.util.Map;
  26 import java.util.Set;
  27 import java.util.Vector;
  28
  29 import android.accounts.Account;
  30 import android.support.v4.app.Fragment;
  31 import android.support.v4.app.FragmentManager;
  32 import android.support.v4.app.FragmentStatePagerAdapter;
  33 import android.view.ViewGroup;
  34
  35 import com.owncloud.android.datamodel.FileDataStorageManager;
  36 import com.owncloud.android.datamodel.OCFile;
  37 import com.owncloud.android.ui.fragment.FileFragment;
  38 import com.owncloud.android.utils.FileStorageUtils;
  39
  40 /**
  41  * Adapter class that provides Fragment instances
  42  */
  43 //public class PreviewImagePagerAdapter extends PagerAdapter {
  44 public class PreviewImagePagerAdapter extends FragmentStatePagerAdapter {
  45
  46     private Vector<OCFile> mImageFiles;
  47     private Account mAccount;
  48     private Set<Object> mObsoleteFragments;
  49     private Set<Integer> mObsoletePositions;
  50     private Set<Integer> mDownloadErrors;
  51     private FileDataStorageManager mStorageManager;
  52
  53     private Map<Integer, FileFragment> mCachedFragments;
  54
  55     /**
  56      * Constructor.
  57      *
  58      * @param fragmentManager   {@link FragmentManager} instance that will handle
  59      *                          the {@link Fragment}s provided by the adapter.
  60      * @param parentFolder      Folder where images will be searched for.
  61      * @param storageManager    Bridge to database.
  62      */
  63     public PreviewImagePagerAdapter(FragmentManager fragmentManager, OCFile parentFolder,
  64                                     Account account, FileDataStorageManager storageManager /*,
  65                                     boolean onlyOnDevice*/) {
  66         super(fragmentManager);
  67
  68         if (fragmentManager == null) {
  69             throw new IllegalArgumentException("NULL FragmentManager instance");
  70         }
  71         if (parentFolder == null) {
  72             throw new IllegalArgumentException("NULL parent folder");
  73         }
  74         if (storageManager == null) {
  75             throw new IllegalArgumentException("NULL storage manager");
  76         }
  77
  78         mAccount = account;
  79         mStorageManager = storageManager;
  80         // TODO Enable when "On Device" is recovered ?
  81         mImageFiles = mStorageManager.getFolderImages(parentFolder/*, false*/);
  82
  83         mImageFiles = FileStorageUtils.sortFolder(mImageFiles);
  84
  85         mObsoleteFragments = new HashSet<Object>();
  86         mObsoletePositions = new HashSet<Integer>();
  87         mDownloadErrors = new HashSet<Integer>();
  88         //mFragmentManager = fragmentManager;
  89         mCachedFragments = new HashMap<Integer, FileFragment>();
  90     }
  91
  92     /**
  93      * Returns the image files handled by the adapter.
  94      *
  95      * @return  A vector with the image files handled by the adapter.
  96      */
  97     protected OCFile getFileAt(int position) {
  98         return mImageFiles.get(position);
  99     }
 100
 101
 102     public Fragment getItem(int i) {
 103         OCFile file = mImageFiles.get(i);
 104         Fragment fragment = null;
 105         if (file.isDown()) {
 106             fragment = PreviewImageFragment.newInstance(file,
 107                     mObsoletePositions.contains(Integer.valueOf(i)));
 108
 109         } else if (mDownloadErrors.contains(Integer.valueOf(i))) {
 110             fragment = FileDownloadFragment.newInstance(file, mAccount, true);
 111             ((FileDownloadFragment)fragment).setError(true);
 112             mDownloadErrors.remove(Integer.valueOf(i));
 113
 114         } else {
 115             fragment = FileDownloadFragment.newInstance(
 116                     file, mAccount, mObsoletePositions.contains(Integer.valueOf(i))
 117             );
 118         }
 119         mObsoletePositions.remove(Integer.valueOf(i));
 120         return fragment;
 121     }
 122
 123     public int getFilePosition(OCFile file) {
 124         return mImageFiles.indexOf(file);
 125     }
 126
 127     @Override
 128     public int getCount() {
 129         return mImageFiles.size();
 130     }
 131
 132     @Override
 133     public CharSequence getPageTitle(int position) {
 134         return mImageFiles.get(position).getFileName();
 135     }
 136
 137
 138     public void updateFile(int position, OCFile file) {
 139         FileFragment fragmentToUpdate = mCachedFragments.get(Integer.valueOf(position));
 140         if (fragmentToUpdate != null) {
 141             mObsoleteFragments.add(fragmentToUpdate);
 142         }
 143         mObsoletePositions.add(Integer.valueOf(position));
 144         mImageFiles.set(position, file);
 145     }
 146
 147
 148     public void updateWithDownloadError(int position) {
 149         FileFragment fragmentToUpdate = mCachedFragments.get(Integer.valueOf(position));
 150         if (fragmentToUpdate != null) {
 151             mObsoleteFragments.add(fragmentToUpdate);
 152         }
 153         mDownloadErrors.add(Integer.valueOf(position));
 154     }
 155
 156     public void clearErrorAt(int position) {
 157         FileFragment fragmentToUpdate = mCachedFragments.get(Integer.valueOf(position));
 158         if (fragmentToUpdate != null) {
 159             mObsoleteFragments.add(fragmentToUpdate);
 160         }
 161         mDownloadErrors.remove(Integer.valueOf(position));
 162     }
 163
 164
 165     @Override
 166     public int getItemPosition(Object object) {
 167         if (mObsoleteFragments.contains(object)) {
 168             mObsoleteFragments.remove(object);
 169             return POSITION_NONE;
 170         }
 171         return super.getItemPosition(object);
 172     }
 173
 174
 175     @Override
 176     public Object instantiateItem(ViewGroup container, int position) {
 177         Object fragment = super.instantiateItem(container, position);
 178         mCachedFragments.put(Integer.valueOf(position), (FileFragment)fragment);
 179         return fragment;
 180     }
 181
 182     @Override
 183     public void destroyItem(ViewGroup container, int position, Object object) {
 184        mCachedFragments.remove(Integer.valueOf(position));
 185        super.destroyItem(container, position, object);
 186     }
 187
 188
 189     public boolean pendingErrorAt(int position) {
 190         return mDownloadErrors.contains(Integer.valueOf(position));
 191     }
 192
 193     /**
 194      * Reset the image zoom to default value for each CachedFragments
 195      */
 196     public void resetZoom() {
 197         Iterator<FileFragment> entries = mCachedFragments.values().iterator();
 198         while (entries.hasNext()) {
 199         FileFragment fileFragment = (FileFragment) entries.next();
 200             if (fileFragment instanceof PreviewImageFragment) {
 201                 ((PreviewImageFragment) fileFragment).getImageView().resetZoom();
 202             }
 203         }
 204     }
 205
 206     /* -*
 207      * Called when a change in the shown pages is going to start being made.
 208      *
 209      * @param   container   The containing View which is displaying this adapter's page views.
 210      *- /
 211     @Override
 212     public void startUpdate(ViewGroup container) {
 213         Log_OC.e(TAG, "** startUpdate");
 214     }
 215
 216     @Override
 217     public Object instantiateItem(ViewGroup container, int position) {
 218         Log_OC.e(TAG, "** instantiateItem " + position);
 219
 220         if (mFragments.size() > position) {
 221             Fragment fragment = mFragments.get(position);
 222             if (fragment != null) {
 223                 Log_OC.e(TAG, "** \t returning cached item");
 224                 return fragment;
 225             }
 226         }
 227
 228         if (mCurTransaction == null) {
 229             mCurTransaction = mFragmentManager.beginTransaction();
 230         }
 231
 232         Fragment fragment = getItem(position);
 233         if (mSavedState.size() > position) {
 234             Fragment.SavedState savedState = mSavedState.get(position);
 235             if (savedState != null) {
 236                 // TODO WATCH OUT:
 237                 // * The Fragment must currently be attached to the FragmentManager.
 238                 // * A new Fragment created using this saved state must be the same class type as the Fragment it was created from.
 239                 // * The saved state can not contain dependencies on other fragments -- that is it can't use putFragment(Bundle, String, Fragment)
 240                 //   to store a fragment reference
 241                 fragment.setInitialSavedState(savedState);
 242             }
 243         }
 244         while (mFragments.size() <= position) {
 245             mFragments.add(null);
 246         }
 247         fragment.setMenuVisibility(false);
 248         mFragments.set(position, fragment);
 249         //Log_OC.e(TAG, "** \t adding fragment at position " + position + ", containerId " + container.getId());
 250         mCurTransaction.add(container.getId(), fragment);
 251
 252         return fragment;
 253     }
 254
 255     @Override
 256     public void destroyItem(ViewGroup container, int position, Object object) {
 257         Log_OC.e(TAG, "** destroyItem " + position);
 258         Fragment fragment = (Fragment)object;
 259
 260         if (mCurTransaction == null) {
 261             mCurTransaction = mFragmentManager.beginTransaction();
 262         }
 263         Log_OC.e(TAG, "** \t removing fragment at position " + position);
 264         while (mSavedState.size() <= position) {
 265             mSavedState.add(null);
 266         }
 267         mSavedState.set(position, mFragmentManager.saveFragmentInstanceState(fragment));
 268         mFragments.set(position, null);
 269
 270         mCurTransaction.remove(fragment);
 271     }
 272
 273     @Override
 274     public void setPrimaryItem(ViewGroup container, int position, Object object) {
 275         Fragment fragment = (Fragment)object;
 276         if (fragment != mCurrentPrimaryItem) {
 277             if (mCurrentPrimaryItem != null) {
 278                 mCurrentPrimaryItem.setMenuVisibility(false);
 279             }
 280             if (fragment != null) {
 281                 fragment.setMenuVisibility(true);
 282             }
 283             mCurrentPrimaryItem = fragment;
 284         }
 285     }
 286
 287     @Override
 288     public void finishUpdate(ViewGroup container) {
 289         Log_OC.e(TAG, "** finishUpdate (start)");
 290         if (mCurTransaction != null) {
 291             mCurTransaction.commitAllowingStateLoss();
 292             mCurTransaction = null;
 293             mFragmentManager.executePendingTransactions();
 294         }
 295         Log_OC.e(TAG, "** finishUpdate (end)");
 296     }
 297
 298     @Override
 299     public boolean isViewFromObject(View view, Object object) {
 300         return ((Fragment)object).getView() == view;
 301     }
 302
 303     @Override
 304     public Parcelable saveState() {
 305         Bundle state = null;
 306         if (mSavedState.size() > 0) {
 307             state = new Bundle();
 308             Fragment.SavedState[] savedStates = new Fragment.SavedState[mSavedState.size()];
 309             mSavedState.toArray(savedStates);
 310             state.putParcelableArray("states", savedStates);
 311         }
 312         for (int i=0; i<mFragments.size(); i++) {
 313             Fragment fragment = mFragments.get(i);
 314             if (fragment != null) {
 315                 if (state == null) {
 316                     state = new Bundle();
 317                 }
 318                 String key = "f" + i;
 319                 mFragmentManager.putFragment(state, key, fragment);
 320             }
 321         }
 322         return state;
 323     }
 324
 325     @Override
 326     public void restoreState(Parcelable state, ClassLoader loader) {
 327         if (state != null) {
 328             Bundle bundle = (Bundle)state;
 329             bundle.setClassLoader(loader);
 330             Parcelable[] states = bundle.getParcelableArray("states");
 331             mSavedState.clear();
 332             mFragments.clear();
 333             if (states != null) {
 334                 for (int i=0; i<states.length; i++) {
 335                     mSavedState.add((Fragment.SavedState)states[i]);
 336                 }
 337             }
 338             Iterable<String> keys = bundle.keySet();
 339             for (String key: keys) {
 340                 if (key.startsWith("f")) {
 341                     int index = Integer.parseInt(key.substring(1));
 342                     Fragment f = mFragmentManager.getFragment(bundle, key);
 343                     if (f != null) {
 344                         while (mFragments.size() <= index) {
 345                             mFragments.add(null);
 346                         }
 347                         f.setMenuVisibility(false);
 348                         mFragments.set(index, f);
 349                     } else {
 350                         Log_OC.w(TAG, "Bad fragment at key " + key);
 351                     }
 352                 }
 353             }
 354         }
 355     }
 356     */
 357 }