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.ListAdapter;
  31 import android.widget.ListView;
  32 import android.widget.TextView;
  33
  34 import com.actionbarsherlock.app.SherlockFragment;
  35 import com.owncloud.android.R;
  36 import com.owncloud.android.lib.common.utils.Log_OC;
  37 import com.owncloud.android.ui.ExtendedListView;
  38 import com.owncloud.android.ui.activity.OnEnforceableRefreshListener;
  39
  40 /**
  41  *  TODO extending SherlockListFragment instead of SherlockFragment
  42  */
  43 public class ExtendedListFragment extends SherlockFragment
  44 implements OnItemClickListener, OnEnforceableRefreshListener {
  45
  46     private static final String TAG = ExtendedListFragment.class.getSimpleName();
  47
  48     private static final String KEY_SAVED_LIST_POSITION = "SAVED_LIST_POSITION";
  49     private static final String KEY_INDEXES = "INDEXES";
  50     private static final String KEY_FIRST_POSITIONS= "FIRST_POSITIONS";
  51     private static final String KEY_TOPS = "TOPS";
  52     private static final String KEY_HEIGHT_CELL = "HEIGHT_CELL";
  53     private static final String KEY_EMPTY_LIST_MESSAGE = "EMPTY_LIST_MESSAGE";
  54
  55     protected ExtendedListView mList;
  56
  57     private SwipeRefreshLayout mRefreshLayout;
  58     private SwipeRefreshLayout mRefreshEmptyLayout;
  59     private TextView mEmptyListMessage;
  60
  61     // Save the state of the scroll in browsing
  62     private ArrayList<Integer> mIndexes;
  63     private ArrayList<Integer> mFirstPositions;
  64     private ArrayList<Integer> mTops;
  65     private int mHeightCell = 0;
  66
  67     private OnEnforceableRefreshListener mOnRefreshListener = null;
  68
  69
  70     public void setListAdapter(ListAdapter listAdapter) {
  71         mList.setAdapter(listAdapter);
  72         mList.invalidate();
  73     }
  74
  75     public ListView getListView() {
  76         return mList;
  77     }
  78
  79
  80     @Override
  81     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
  82         Log_OC.e(TAG, "onCreateView");
  83
  84         View v = inflater.inflate(R.layout.list_fragment, null);
  85         mEmptyListMessage = (TextView) v.findViewById(R.id.empty_list_view);
  86         mList = (ExtendedListView)(v.findViewById(R.id.list_root));
  87         mList.setOnItemClickListener(this);
  88
  89         mList.setDivider(getResources().getDrawable(R.drawable.uploader_list_separator));
  90         mList.setDividerHeight(1);
  91
  92         if (savedInstanceState != null) {
  93             int referencePosition = savedInstanceState.getInt(KEY_SAVED_LIST_POSITION);
  94             setReferencePosition(referencePosition);
  95         }
  96
  97         // Pull down refresh
  98         mRefreshLayout = (SwipeRefreshLayout) v.findViewById(R.id.swipe_refresh_files);
  99         mRefreshEmptyLayout = (SwipeRefreshLayout) v.findViewById(R.id.swipe_refresh_files_emptyView);
 100
 101         onCreateSwipeToRefresh(mRefreshLayout);
 102         onCreateSwipeToRefresh(mRefreshEmptyLayout);
 103
 104         mList.setEmptyView(mRefreshEmptyLayout);
 105
 106         return v;
 107     }
 108
 109
 110     /**
 111      * {@inheritDoc}
 112      */
 113     @Override
 114     public void onActivityCreated(Bundle savedInstanceState) {
 115         super.onActivityCreated(savedInstanceState);
 116
 117         if (savedInstanceState != null) {
 118             mIndexes = savedInstanceState.getIntegerArrayList(KEY_INDEXES);
 119             mFirstPositions = savedInstanceState.getIntegerArrayList(KEY_FIRST_POSITIONS);
 120             mTops = savedInstanceState.getIntegerArrayList(KEY_TOPS);
 121             mHeightCell = savedInstanceState.getInt(KEY_HEIGHT_CELL);
 122             setMessageForEmptyList(savedInstanceState.getString(KEY_EMPTY_LIST_MESSAGE));
 123
 124         } else {
 125             mIndexes = new ArrayList<Integer>();
 126             mFirstPositions = new ArrayList<Integer>();
 127             mTops = new ArrayList<Integer>();
 128             mHeightCell = 0;
 129         }
 130     }
 131
 132
 133     @Override
 134     public void onSaveInstanceState(Bundle savedInstanceState) {
 135         super.onSaveInstanceState(savedInstanceState);
 136         Log_OC.e(TAG, "onSaveInstanceState()");
 137         savedInstanceState.putInt(KEY_SAVED_LIST_POSITION, getReferencePosition());
 138         savedInstanceState.putIntegerArrayList(KEY_INDEXES, mIndexes);
 139         savedInstanceState.putIntegerArrayList(KEY_FIRST_POSITIONS, mFirstPositions);
 140         savedInstanceState.putIntegerArrayList(KEY_TOPS, mTops);
 141         savedInstanceState.putInt(KEY_HEIGHT_CELL, mHeightCell);
 142         savedInstanceState.putString(KEY_EMPTY_LIST_MESSAGE, getEmptyViewText());
 143     }
 144
 145
 146     /**
 147      * Calculates the position of the item that will be used as a reference to reposition the visible items in the list when
 148      * the device is turned to other position.
 149      *
 150      * THe current policy is take as a reference the visible item in the center of the screen.
 151      *
 152      * @return      The position in the list of the visible item in the center of the screen.
 153      */
 154     protected int getReferencePosition() {
 155         if (mList != null) {
 156             return (mList.getFirstVisiblePosition() + mList.getLastVisiblePosition()) / 2;
 157         } else {
 158             return 0;
 159         }
 160     }
 161
 162
 163     /**
 164      * Sets the visible part of the list from the reference position.
 165      *
 166      * @param   position    Reference position previously returned by {@link LocalFileListFragment#getReferencePosition()}
 167      */
 168     protected void setReferencePosition(int position) {
 169         if (mList != null) {
 170             mList.setAndCenterSelection(position);
 171         }
 172     }
 173
 174
 175     /*
 176      * Restore index and position
 177      */
 178     protected void restoreIndexAndTopPosition() {
 179         if (mIndexes.size() > 0) {
 180             // needs to be checked; not every browse-up had a browse-down before
 181
 182             int index = mIndexes.remove(mIndexes.size() - 1);
 183
 184             int firstPosition = mFirstPositions.remove(mFirstPositions.size() -1);
 185
 186             int top = mTops.remove(mTops.size() - 1);
 187
 188             mList.setSelectionFromTop(firstPosition, top);
 189
 190             // Move the scroll if the selection is not visible
 191             int indexPosition = mHeightCell*index;
 192             int height = mList.getHeight();
 193
 194             if (indexPosition > height) {
 195                 if (android.os.Build.VERSION.SDK_INT >= 11)
 196                 {
 197                     mList.smoothScrollToPosition(index);
 198                 }
 199                 else if (android.os.Build.VERSION.SDK_INT >= 8)
 200                 {
 201                     mList.setSelectionFromTop(index, 0);
 202                 }
 203
 204             }
 205         }
 206     }
 207
 208     /*
 209      * Save index and top position
 210      */
 211     protected void saveIndexAndTopPosition(int index) {
 212
 213         mIndexes.add(index);
 214
 215         int firstPosition = mList.getFirstVisiblePosition();
 216         mFirstPositions.add(firstPosition);
 217
 218         View view = mList.getChildAt(0);
 219         int top = (view == null) ? 0 : view.getTop() ;
 220
 221         mTops.add(top);
 222
 223         // Save the height of a cell
 224         mHeightCell = (view == null || mHeightCell != 0) ? mHeightCell : view.getHeight();
 225     }
 226
 227
 228     @Override
 229     public void onItemClick (AdapterView<?> parent, View view, int position, long id) {
 230         // to be @overriden
 231     }
 232
 233     @Override
 234     public void onRefresh() {
 235         // to be @overriden
 236         mRefreshLayout.setRefreshing(false);
 237         mRefreshEmptyLayout.setRefreshing(false);
 238
 239         if (mOnRefreshListener != null) {
 240             mOnRefreshListener.onRefresh();
 241         }
 242     }
 243
 244     public void setOnRefreshListener(OnEnforceableRefreshListener listener) {
 245         mOnRefreshListener = listener;
 246     }
 247
 248
 249     /**
 250      * Enables swipe gesture
 251      */
 252     public void enableSwipe() {
 253         mRefreshLayout.setEnabled(true);
 254     }
 255
 256     /**
 257      * Disables swipe gesture. It prevents manual gestures but keeps the option you show
 258      * refreshing programmatically.
 259      */
 260     public void disableSwipe() {
 261         mRefreshLayout.setEnabled(false);
 262     }
 263
 264     /**
 265      * It shows the SwipeRefreshLayout progress
 266      */
 267     public void showSwipeProgress() {
 268         mRefreshLayout.setRefreshing(true);
 269     }
 270
 271     /**
 272      * It shows the SwipeRefreshLayout progress
 273      */
 274     public void hideSwipeProgress() {
 275         mRefreshLayout.setRefreshing(false);
 276     }
 277
 278     /**
 279      * Set message for empty list view
 280      */
 281     public void setMessageForEmptyList(String message) {
 282         if (mEmptyListMessage != null) {
 283             mEmptyListMessage.setText(message);
 284         }
 285     }
 286
 287     /**
 288      * Get the text of EmptyListMessage TextView
 289      *
 290      * @return String
 291      */
 292     public String getEmptyViewText() {
 293         return (mEmptyListMessage != null) ? mEmptyListMessage.getText().toString() : "";
 294     }
 295
 296     private void onCreateSwipeToRefresh(SwipeRefreshLayout refreshLayout) {
 297         // Colors in animations: background
 298         refreshLayout.setColorScheme(R.color.background_color, R.color.background_color, R.color.background_color,
 299                 R.color.background_color);
 300
 301         refreshLayout.setOnRefreshListener(this);
 302     }
 303
 304     @Override
 305     public void onRefresh(boolean ignoreETag) {
 306         mRefreshLayout.setRefreshing(false);
 307         mRefreshEmptyLayout.setRefreshing(false);
 308
 309         if (mOnRefreshListener != null) {
 310             mOnRefreshListener.onRefresh(ignoreETag);
 311         }
 312     }
 313 }