src/com/owncloud/android/ui/fragment/ExtendedListFragment.java

   1 /* ownCloud Android client application
   2  *   Copyright (C) 2012 Bartek Przybylski
   3  *   Copyright (C) 2012-2013 ownCloud Inc.
   4  *
   5  *   This program is free software: you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License version 2,
   7  *   as published by the Free Software Foundation.
   8  *
   9  *   This program is distributed in the hope that it will be useful,
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *   GNU General Public License for more details.
  13  *
  14  *   You should have received a copy of the GNU General Public License
  15  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  *
  17  */
  18
  19 package com.owncloud.android.ui.fragment;
  20
  21 import java.util.ArrayList;
  22
  23 import android.os.Bundle;
  24 import android.support.v4.widget.SwipeRefreshLayout;
  25 import android.view.LayoutInflater;
  26 import android.view.View;
  27 import android.view.ViewGroup;
  28 import android.widget.AdapterView;
  29 import android.widget.AdapterView.OnItemClickListener;
  30 import android.widget.GridView;
  31 import android.widget.ListAdapter;
  32 import android.widget.ListView;
  33 import android.widget.TextView;
  34
  35 import com.actionbarsherlock.app.SherlockFragment;
  36 import com.owncloud.android.R;
  37 import com.owncloud.android.lib.common.utils.Log_OC;
  38 import com.owncloud.android.ui.ExtendedListView;
  39 import com.owncloud.android.ui.activity.OnEnforceableRefreshListener;
  40
  41 /**
  42  *  TODO extending SherlockListFragment instead of SherlockFragment
  43  */
  44 public class ExtendedListFragment extends SherlockFragment
  45 implements OnItemClickListener, OnEnforceableRefreshListener {
  46
  47     private static final String TAG = ExtendedListFragment.class.getSimpleName();
  48
  49     private static final String KEY_SAVED_LIST_POSITION = "SAVED_LIST_POSITION";
  50     private static final String KEY_INDEXES = "INDEXES";
  51     private static final String KEY_FIRST_POSITIONS= "FIRST_POSITIONS";
  52     private static final String KEY_TOPS = "TOPS";
  53     private static final String KEY_HEIGHT_CELL = "HEIGHT_CELL";
  54     private static final String KEY_EMPTY_LIST_MESSAGE = "EMPTY_LIST_MESSAGE";
  55
  56     protected ExtendedListView mList;
  57
  58     private SwipeRefreshLayout mRefreshLayout;
  59     private SwipeRefreshLayout mRefreshEmptyLayout;
  60     private TextView mEmptyListMessage;
  61
  62     // Save the state of the scroll in browsing
  63     private ArrayList<Integer> mIndexes;
  64     private ArrayList<Integer> mFirstPositions;
  65     private ArrayList<Integer> mTops;
  66     private int mHeightCell = 0;
  67
  68     private OnEnforceableRefreshListener mOnRefreshListener = null;
  69
  70     protected GridView imageView;
  71
  72     public void setListAdapter(ListAdapter listAdapter) {
  73         imageView.setAdapter(listAdapter);
  74         imageView.invalidate();
  75     }
  76
  77     public GridView getGridView() {
  78         return imageView;
  79     }
  80
  81     protected void switchImageView(){
  82        imageView.setNumColumns(GridView.AUTO_FIT);
  83        imageView.invalidate();
  84     }
  85
  86     protected void switchFileView(){
  87        imageView.setNumColumns(1);
  88        imageView.invalidate();
  89     }
  90
  91
  92     @Override
  93     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
  94         Log_OC.e(TAG, "onCreateView");
  95
  96         View v = inflater.inflate(R.layout.list_fragment, null);
  97
  98         imageView = (ExtendedListView)(v.findViewById(R.id.list_root));
  99         imageView.setOnItemClickListener(this);
 100
 101         if (savedInstanceState != null) {
 102             int referencePosition = savedInstanceState.getInt(KEY_SAVED_LIST_POSITION);
 103             setReferencePosition(referencePosition);
 104         }
 105
 106         // Pull down refresh
 107         mRefreshLayout = (SwipeRefreshLayout) v.findViewById(R.id.swipe_refresh_files);
 108         mRefreshEmptyLayout = (SwipeRefreshLayout) v.findViewById(R.id.swipe_refresh_files_emptyView);
 109
 110         onCreateSwipeToRefresh(mRefreshLayout);
 111         onCreateSwipeToRefresh(mRefreshEmptyLayout);
 112
 113         return v;
 114     }
 115
 116
 117     /**
 118      * {@inheritDoc}
 119      */
 120     @Override
 121     public void onActivityCreated(Bundle savedInstanceState) {
 122         super.onActivityCreated(savedInstanceState);
 123
 124         if (savedInstanceState != null) {
 125             mIndexes = savedInstanceState.getIntegerArrayList(KEY_INDEXES);
 126             mFirstPositions = savedInstanceState.getIntegerArrayList(KEY_FIRST_POSITIONS);
 127             mTops = savedInstanceState.getIntegerArrayList(KEY_TOPS);
 128             mHeightCell = savedInstanceState.getInt(KEY_HEIGHT_CELL);
 129             setMessageForEmptyList(savedInstanceState.getString(KEY_EMPTY_LIST_MESSAGE));
 130
 131         } else {
 132             mIndexes = new ArrayList<Integer>();
 133             mFirstPositions = new ArrayList<Integer>();
 134             mTops = new ArrayList<Integer>();
 135             mHeightCell = 0;
 136         }
 137     }
 138
 139
 140     @Override
 141     public void onSaveInstanceState(Bundle savedInstanceState) {
 142         super.onSaveInstanceState(savedInstanceState);
 143         Log_OC.e(TAG, "onSaveInstanceState()");
 144         savedInstanceState.putInt(KEY_SAVED_LIST_POSITION, getReferencePosition());
 145         savedInstanceState.putIntegerArrayList(KEY_INDEXES, mIndexes);
 146         savedInstanceState.putIntegerArrayList(KEY_FIRST_POSITIONS, mFirstPositions);
 147         savedInstanceState.putIntegerArrayList(KEY_TOPS, mTops);
 148         savedInstanceState.putInt(KEY_HEIGHT_CELL, mHeightCell);
 149         savedInstanceState.putString(KEY_EMPTY_LIST_MESSAGE, getEmptyViewText());
 150     }
 151
 152
 153     /**
 154      * Calculates the position of the item that will be used as a reference to reposition the visible items in the list when
 155      * the device is turned to other position.
 156      *
 157      * THe current policy is take as a reference the visible item in the center of the screen.
 158      *
 159      * @return      The position in the list of the visible item in the center of the screen.
 160      */
 161     protected int getReferencePosition() {
 162         if (imageView != null) {
 163             return (imageView.getFirstVisiblePosition() + imageView.getLastVisiblePosition()) / 2;
 164         } else {
 165             return 0;
 166         }
 167     }
 168
 169
 170     /**
 171      * Sets the visible part of the list from the reference position.
 172      *
 173      * @param   position    Reference position previously returned by {@link LocalFileListFragment#getReferencePosition()}
 174      */
 175     protected void setReferencePosition(int position) {
 176         if (imageView != null) {
 177             imageView.setSelection(position);
 178         }
 179     }
 180
 181
 182     /*
 183      * Restore index and position
 184      */
 185     protected void restoreIndexAndTopPosition() {
 186         if (mIndexes.size() > 0) {
 187             // needs to be checked; not every browse-up had a browse-down before
 188
 189             int index = mIndexes.remove(mIndexes.size() - 1);
 190
 191             int firstPosition = mFirstPositions.remove(mFirstPositions.size() -1);
 192
 193             int top = mTops.remove(mTops.size() - 1);
 194
 195             imageView.smoothScrollToPosition(firstPosition);
 196
 197             // Move the scroll if the selection is not visible
 198             int indexPosition = mHeightCell*index;
 199             int height = imageView.getHeight();
 200
 201             if (indexPosition > height) {
 202                 imageView.smoothScrollToPosition(index);
 203             }
 204         }
 205     }
 206
 207     /*
 208      * Save index and top position
 209      */
 210     protected void saveIndexAndTopPosition(int index) {
 211
 212         mIndexes.add(index);
 213
 214         int firstPosition = imageView.getFirstVisiblePosition();
 215         mFirstPositions.add(firstPosition);
 216
 217         View view = imageView.getChildAt(0);
 218         int top = (view == null) ? 0 : view.getTop() ;
 219
 220         mTops.add(top);
 221
 222         // Save the height of a cell
 223         mHeightCell = (view == null || mHeightCell != 0) ? mHeightCell : view.getHeight();
 224     }
 225
 226
 227     @Override
 228     public void onItemClick (AdapterView<?> parent, View view, int position, long id) {
 229         // to be @overriden
 230     }
 231
 232     @Override
 233     public void onRefresh() {
 234         // to be @overriden
 235         mRefreshLayout.setRefreshing(false);
 236         mRefreshEmptyLayout.setRefreshing(false);
 237
 238         if (mOnRefreshListener != null) {
 239             mOnRefreshListener.onRefresh();
 240         }
 241     }
 242
 243     public void setOnRefreshListener(OnEnforceableRefreshListener listener) {
 244         mOnRefreshListener = listener;
 245     }
 246
 247
 248     /**
 249      * Enables swipe gesture
 250      */
 251     public void enableSwipe() {
 252         mRefreshLayout.setEnabled(true);
 253     }
 254
 255     /**
 256      * Disables swipe gesture. It prevents manual gestures but keeps the option you show
 257      * refreshing programmatically.
 258      */
 259     public void disableSwipe() {
 260         mRefreshLayout.setEnabled(false);
 261     }
 262
 263     /**
 264      * It shows the SwipeRefreshLayout progress
 265      */
 266     public void showSwipeProgress() {
 267         mRefreshLayout.setRefreshing(true);
 268     }
 269
 270     /**
 271      * It shows the SwipeRefreshLayout progress
 272      */
 273     public void hideSwipeProgress() {
 274         mRefreshLayout.setRefreshing(false);
 275     }
 276
 277     /**
 278      * Set message for empty list view
 279      */
 280     public void setMessageForEmptyList(String message) {
 281         if (mEmptyListMessage != null) {
 282             mEmptyListMessage.setText(message);
 283         }
 284     }
 285
 286     /**
 287      * Get the text of EmptyListMessage TextView
 288      *
 289      * @return String
 290      */
 291     public String getEmptyViewText() {
 292         return (mEmptyListMessage != null) ? mEmptyListMessage.getText().toString() : "";
 293     }
 294
 295     private void onCreateSwipeToRefresh(SwipeRefreshLayout refreshLayout) {
 296         // Colors in animations: background
 297         refreshLayout.setColorScheme(R.color.background_color, R.color.background_color, R.color.background_color,
 298                 R.color.background_color);
 299
 300         refreshLayout.setOnRefreshListener(this);
 301     }
 302
 303     @Override
 304     public void onRefresh(boolean ignoreETag) {
 305         mRefreshLayout.setRefreshing(false);
 306         mRefreshEmptyLayout.setRefreshing(false);
 307
 308         if (mOnRefreshListener != null) {
 309             mOnRefreshListener.onRefresh(ignoreETag);
 310         }
 311     }
 312 }