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

   1 /* ownCloud Android client application
   2  *   Copyright (C) 2012-2013  ownCloud Inc.
   3  *
   4  *   This program is free software: you can redistribute it and/or modify
   5  *   it under the terms of the GNU General Public License version 2,
   6  *   as published by the Free Software Foundation.
   7  *
   8  *   This program is distributed in the hope that it will be useful,
   9  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  *   GNU General Public License for more details.
  12  *
  13  *   You should have received a copy of the GNU General Public License
  14  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  *
  16  */
  17 package com.owncloud.android.ui.preview;
  18
  19 import java.util.ArrayList;
  20 import java.util.HashMap;
  21 import java.util.HashSet;
  22 import java.util.Map;
  23 import java.util.Set;
  24 import java.util.Vector;
  25
  26 import android.accounts.Account;
  27 import android.os.Bundle;
  28 import android.os.Parcelable;
  29 import android.support.v4.app.Fragment;
  30 import android.support.v4.app.FragmentManager;
  31 import android.support.v4.app.FragmentStatePagerAdapter;
  32 import android.support.v4.app.FragmentTransaction;
  33 import android.support.v4.view.PagerAdapter;
  34 import android.support.v4.view.ViewPager;
  35 import android.util.Log;
  36 import android.view.View;
  37 import android.view.ViewGroup;
  38
  39 import com.owncloud.android.datamodel.DataStorageManager;
  40 import com.owncloud.android.datamodel.OCFile;
  41 import com.owncloud.android.ui.fragment.FileFragment;
  42
  43 /**
  44  * Adapter class that provides Fragment instances
  45  *
  46  * @author David A. Velasco
  47  */
  48 //public class PreviewImagePagerAdapter extends PagerAdapter {
  49 public class PreviewImagePagerAdapter extends FragmentStatePagerAdapter {
  50
  51     private static final String TAG = PreviewImagePagerAdapter.class.getSimpleName();
  52
  53     private Vector<OCFile> mImageFiles;
  54     private Account mAccount;
  55     private Set<Object> mObsoleteFragments;
  56     private Set<Integer> mObsoletePositions;
  57     private Set<Integer> mDownloadErrors;
  58     private DataStorageManager mStorageManager;
  59
  60     private Map<Integer, FileFragment> mCachedFragments;
  61
  62     /*
  63     private final FragmentManager mFragmentManager;
  64     private FragmentTransaction mCurTransaction = null;
  65     private ArrayList<Fragment.SavedState> mSavedState = new ArrayList<Fragment.SavedState>();
  66     private ArrayList<Fragment> mFragments = new ArrayList<Fragment>();
  67     private Fragment mCurrentPrimaryItem = null;
  68     */
  69
  70     /**
  71      * Constructor.
  72      *
  73      * @param fragmentManager   {@link FragmentManager} instance that will handle the {@link Fragment}s provided by the adapter.
  74      * @param parentFolder      Folder where images will be searched for.
  75      * @param storageManager    Bridge to database.
  76      */
  77     public PreviewImagePagerAdapter(FragmentManager fragmentManager, OCFile parentFolder, Account account, DataStorageManager storageManager) {
  78         super(fragmentManager);
  79
  80         if (fragmentManager == null) {
  81             throw new IllegalArgumentException("NULL FragmentManager instance");
  82         }
  83         if (parentFolder == null) {
  84             throw new IllegalArgumentException("NULL parent folder");
  85         }
  86         if (storageManager == null) {
  87             throw new IllegalArgumentException("NULL storage manager");
  88         }
  89
  90         mAccount = account;
  91         mStorageManager = storageManager;
  92         mImageFiles = mStorageManager.getDirectoryImages(parentFolder);
  93         mObsoleteFragments = new HashSet<Object>();
  94         mObsoletePositions = new HashSet<Integer>();
  95         mDownloadErrors = new HashSet<Integer>();
  96         //mFragmentManager = fragmentManager;
  97         mCachedFragments = new HashMap<Integer, FileFragment>();
  98     }
  99
 100
 101     /**
 102      * Returns the image files handled by the adapter.
 103      *
 104      * @return  A vector with the image files handled by the adapter.
 105      */
 106     protected OCFile getFileAt(int position) {
 107         return mImageFiles.get(position);
 108     }
 109
 110
 111     public Fragment getItem(int i) {
 112         OCFile file = mImageFiles.get(i);
 113         Fragment fragment = null;
 114         if (file.isDown()) {
 115             fragment = new PreviewImageFragment(file, mAccount, mObsoletePositions.contains(Integer.valueOf(i)));
 116
 117         } else if (mDownloadErrors.contains(Integer.valueOf(i))) {
 118             fragment = new FileDownloadFragment(file, mAccount, true);
 119             ((FileDownloadFragment)fragment).setError(true);
 120             mDownloadErrors.remove(Integer.valueOf(i));
 121
 122         } else {
 123             fragment = new FileDownloadFragment(file, mAccount, mObsoletePositions.contains(Integer.valueOf(i)));
 124         }
 125         mObsoletePositions.remove(Integer.valueOf(i));
 126         return fragment;
 127     }
 128
 129     public int getFilePosition(OCFile file) {
 130         return mImageFiles.indexOf(file);
 131     }
 132
 133     @Override
 134     public int getCount() {
 135         return mImageFiles.size();
 136     }
 137
 138     @Override
 139     public CharSequence getPageTitle(int position) {
 140         return mImageFiles.get(position).getFileName();
 141     }
 142
 143
 144     public void updateFile(int position, OCFile file) {
 145         FileFragment fragmentToUpdate = mCachedFragments.get(Integer.valueOf(position));
 146         if (fragmentToUpdate != null) {
 147             mObsoleteFragments.add(fragmentToUpdate);
 148         }
 149         mObsoletePositions.add(Integer.valueOf(position));
 150         mImageFiles.set(position, file);
 151     }
 152
 153
 154     public void updateWithDownloadError(int position) {
 155         FileFragment fragmentToUpdate = mCachedFragments.get(Integer.valueOf(position));
 156         if (fragmentToUpdate != null) {
 157             mObsoleteFragments.add(fragmentToUpdate);
 158         }
 159         mDownloadErrors.add(Integer.valueOf(position));
 160     }
 161
 162     public void clearErrorAt(int position) {
 163         FileFragment fragmentToUpdate = mCachedFragments.get(Integer.valueOf(position));
 164         if (fragmentToUpdate != null) {
 165             mObsoleteFragments.add(fragmentToUpdate);
 166         }
 167         mDownloadErrors.remove(Integer.valueOf(position));
 168     }
 169
 170
 171     @Override
 172     public int getItemPosition(Object object) {
 173         if (mObsoleteFragments.contains(object)) {
 174             mObsoleteFragments.remove(object);
 175             return POSITION_NONE;
 176         }
 177         return super.getItemPosition(object);
 178     }
 179
 180
 181     @Override
 182     public Object instantiateItem(ViewGroup container, int position) {
 183         Object fragment = super.instantiateItem(container, position);
 184         mCachedFragments.put(Integer.valueOf(position), (FileFragment)fragment);
 185         return fragment;
 186     }
 187
 188     @Override
 189     public void destroyItem(ViewGroup container, int position, Object object) {
 190        mCachedFragments.remove(Integer.valueOf(position));
 191        super.destroyItem(container, position, object);
 192     }
 193
 194
 195     public boolean pendingErrorAt(int position) {
 196         return mDownloadErrors.contains(Integer.valueOf(position));
 197     }
 198
 199
 200
 201     /* -*
 202      * Called when a change in the shown pages is going to start being made.
 203      *
 204      * @param   container   The containing View which is displaying this adapter's page views.
 205      *- /
 206     @Override
 207     public void startUpdate(ViewGroup container) {
 208         Log.e(TAG, "** startUpdate");
 209     }
 210
 211     @Override
 212     public Object instantiateItem(ViewGroup container, int position) {
 213         Log.e(TAG, "** instantiateItem " + position);
 214
 215         if (mFragments.size() > position) {
 216             Fragment fragment = mFragments.get(position);
 217             if (fragment != null) {
 218                 Log.e(TAG, "** \t returning cached item");
 219                 return fragment;
 220             }
 221         }
 222
 223         if (mCurTransaction == null) {
 224             mCurTransaction = mFragmentManager.beginTransaction();
 225         }
 226
 227         Fragment fragment = getItem(position);
 228         if (mSavedState.size() > position) {
 229             Fragment.SavedState savedState = mSavedState.get(position);
 230             if (savedState != null) {
 231                 // TODO WATCH OUT:
 232                 // * The Fragment must currently be attached to the FragmentManager.
 233                 // * A new Fragment created using this saved state must be the same class type as the Fragment it was created from.
 234                 // * The saved state can not contain dependencies on other fragments -- that is it can't use putFragment(Bundle, String, Fragment)
 235                 //   to store a fragment reference
 236                 fragment.setInitialSavedState(savedState);
 237             }
 238         }
 239         while (mFragments.size() <= position) {
 240             mFragments.add(null);
 241         }
 242         fragment.setMenuVisibility(false);
 243         mFragments.set(position, fragment);
 244         //Log.e(TAG, "** \t adding fragment at position " + position + ", containerId " + container.getId());
 245         mCurTransaction.add(container.getId(), fragment);
 246
 247         return fragment;
 248     }
 249
 250     @Override
 251     public void destroyItem(ViewGroup container, int position, Object object) {
 252         Log.e(TAG, "** destroyItem " + position);
 253         Fragment fragment = (Fragment)object;
 254
 255         if (mCurTransaction == null) {
 256             mCurTransaction = mFragmentManager.beginTransaction();
 257         }
 258         Log.e(TAG, "** \t removing fragment at position " + position);
 259         while (mSavedState.size() <= position) {
 260             mSavedState.add(null);
 261         }
 262         mSavedState.set(position, mFragmentManager.saveFragmentInstanceState(fragment));
 263         mFragments.set(position, null);
 264
 265         mCurTransaction.remove(fragment);
 266     }
 267
 268     @Override
 269     public void setPrimaryItem(ViewGroup container, int position, Object object) {
 270         Fragment fragment = (Fragment)object;
 271         if (fragment != mCurrentPrimaryItem) {
 272             if (mCurrentPrimaryItem != null) {
 273                 mCurrentPrimaryItem.setMenuVisibility(false);
 274             }
 275             if (fragment != null) {
 276                 fragment.setMenuVisibility(true);
 277             }
 278             mCurrentPrimaryItem = fragment;
 279         }
 280     }
 281
 282     @Override
 283     public void finishUpdate(ViewGroup container) {
 284         Log.e(TAG, "** finishUpdate (start)");
 285         if (mCurTransaction != null) {
 286             mCurTransaction.commitAllowingStateLoss();
 287             mCurTransaction = null;
 288             mFragmentManager.executePendingTransactions();
 289         }
 290         Log.e(TAG, "** finishUpdate (end)");
 291     }
 292
 293     @Override
 294     public boolean isViewFromObject(View view, Object object) {
 295         return ((Fragment)object).getView() == view;
 296     }
 297
 298     @Override
 299     public Parcelable saveState() {
 300         Bundle state = null;
 301         if (mSavedState.size() > 0) {
 302             state = new Bundle();
 303             Fragment.SavedState[] savedStates = new Fragment.SavedState[mSavedState.size()];
 304             mSavedState.toArray(savedStates);
 305             state.putParcelableArray("states", savedStates);
 306         }
 307         for (int i=0; i<mFragments.size(); i++) {
 308             Fragment fragment = mFragments.get(i);
 309             if (fragment != null) {
 310                 if (state == null) {
 311                     state = new Bundle();
 312                 }
 313                 String key = "f" + i;
 314                 mFragmentManager.putFragment(state, key, fragment);
 315             }
 316         }
 317         return state;
 318     }
 319
 320     @Override
 321     public void restoreState(Parcelable state, ClassLoader loader) {
 322         if (state != null) {
 323             Bundle bundle = (Bundle)state;
 324             bundle.setClassLoader(loader);
 325             Parcelable[] states = bundle.getParcelableArray("states");
 326             mSavedState.clear();
 327             mFragments.clear();
 328             if (states != null) {
 329                 for (int i=0; i<states.length; i++) {
 330                     mSavedState.add((Fragment.SavedState)states[i]);
 331                 }
 332             }
 333             Iterable<String> keys = bundle.keySet();
 334             for (String key: keys) {
 335                 if (key.startsWith("f")) {
 336                     int index = Integer.parseInt(key.substring(1));
 337                     Fragment f = mFragmentManager.getFragment(bundle, key);
 338                     if (f != null) {
 339                         while (mFragments.size() <= index) {
 340                             mFragments.add(null);
 341                         }
 342                         f.setMenuVisibility(false);
 343                         mFragments.set(index, f);
 344                     } else {
 345                         Log.w(TAG, "Bad fragment at key " + key);
 346                     }
 347                 }
 348             }
 349         }
 350     }
 351     */
 352 }