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.ui.ExtendedListView;
  37 import com.owncloud.android.utils.Log_OC;
  38
  39 /**
  40  *  TODO extending SherlockListFragment instead of SherlockFragment
  41  */
  42 public class ExtendedListFragment extends SherlockFragment
  43 implements OnItemClickListener, SwipeRefreshLayout.OnRefreshListener {
  44
  45     private static final String TAG = ExtendedListFragment.class.getSimpleName();
  46
  47     private static final String KEY_SAVED_LIST_POSITION = "SAVED_LIST_POSITION";
  48     private static final String KEY_INDEXES = "INDEXES";
  49     private static final String KEY_FIRST_POSITIONS= "FIRST_POSITIONS";
  50     private static final String KEY_TOPS = "TOPS";
  51     private static final String KEY_HEIGHT_CELL = "HEIGHT_CELL";
  52     private static final String KEY_EMPTY_LIST_MESSAGE = "EMPTY_LIST_MESSAGE";
  53
  54     protected ExtendedListView mList;
  55
  56     private SwipeRefreshLayout mRefreshLayout;
  57     private SwipeRefreshLayout mRefreshEmptyLayout;
  58     private TextView mEmptyListMessage;
  59
  60     // Save the state of the scroll in browsing
  61     private ArrayList<Integer> mIndexes;
  62     private ArrayList<Integer> mFirstPositions;
  63     private ArrayList<Integer> mTops;
  64     private int mHeightCell = 0;
  65
  66     private SwipeRefreshLayout.OnRefreshListener mOnRefreshListener = null;
  67
  68
  69     public void setListAdapter(ListAdapter listAdapter) {
  70         mList.setAdapter(listAdapter);
  71         mList.invalidate();
  72     }
  73
  74     public ListView getListView() {
  75         return mList;
  76     }
  77
  78
  79     @Override
  80     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
  81         Log_OC.e(TAG, "onCreateView");
  82
  83         View v = inflater.inflate(R.layout.list_fragment, null);
  84         mEmptyListMessage = (TextView) v.findViewById(R.id.empty_list_view);
  85         mList = (ExtendedListView)(v.findViewById(R.id.list_root));
  86         mList.setOnItemClickListener(this);
  87
  88         mList.setDivider(getResources().getDrawable(R.drawable.uploader_list_separator));
  89         mList.setDividerHeight(1);
  90
  91         if (savedInstanceState != null) {
  92             int referencePosition = savedInstanceState.getInt(KEY_SAVED_LIST_POSITION);
  93             setReferencePosition(referencePosition);
  94         }
  95
  96         // Pull down refresh
  97         mRefreshLayout = (SwipeRefreshLayout) v.findViewById(R.id.swipe_refresh_files);
  98         mRefreshEmptyLayout = (SwipeRefreshLayout) v.findViewById(R.id.swipe_refresh_files_emptyView);
  99
 100         onCreateSwipeToRefresh(mRefreshLayout);
 101         onCreateSwipeToRefresh(mRefreshEmptyLayout);
 102
 103         mList.setEmptyView(mRefreshEmptyLayout);
 104
 105         return v;
 106     }
 107
 108
 109     /**
 110      * {@inheritDoc}
 111      */
 112     @Override
 113     public void onActivityCreated(Bundle savedInstanceState) {
 114         super.onActivityCreated(savedInstanceState);
 115
 116         if (savedInstanceState != null) {
 117             mIndexes = savedInstanceState.getIntegerArrayList(KEY_INDEXES);
 118             mFirstPositions = savedInstanceState.getIntegerArrayList(KEY_FIRST_POSITIONS);
 119             mTops = savedInstanceState.getIntegerArrayList(KEY_TOPS);
 120             mHeightCell = savedInstanceState.getInt(KEY_HEIGHT_CELL);
 121             setMessageForEmptyList(savedInstanceState.getString(KEY_EMPTY_LIST_MESSAGE));
 122
 123         } else {
 124             mIndexes = new ArrayList<Integer>();
 125             mFirstPositions = new ArrayList<Integer>();
 126             mTops = new ArrayList<Integer>();
 127             mHeightCell = 0;
 128         }
 129     }
 130
 131
 132     @Override
 133     public void onSaveInstanceState(Bundle savedInstanceState) {
 134         super.onSaveInstanceState(savedInstanceState);
 135         Log_OC.e(TAG, "onSaveInstanceState()");
 136         savedInstanceState.putInt(KEY_SAVED_LIST_POSITION, getReferencePosition());
 137         savedInstanceState.putIntegerArrayList(KEY_INDEXES, mIndexes);
 138         savedInstanceState.putIntegerArrayList(KEY_FIRST_POSITIONS, mFirstPositions);
 139         savedInstanceState.putIntegerArrayList(KEY_TOPS, mTops);
 140         savedInstanceState.putInt(KEY_HEIGHT_CELL, mHeightCell);
 141         savedInstanceState.putString(KEY_EMPTY_LIST_MESSAGE, getEmptyViewText());
 142     }
 143
 144
 145     /**
 146      * Calculates the position of the item that will be used as a reference to reposition the visible items in the list when
 147      * the device is turned to other position.
 148      *
 149      * THe current policy is take as a reference the visible item in the center of the screen.
 150      *
 151      * @return      The position in the list of the visible item in the center of the screen.
 152      */
 153     protected int getReferencePosition() {
 154         if (mList != null) {
 155             return (mList.getFirstVisiblePosition() + mList.getLastVisiblePosition()) / 2;
 156         } else {
 157             return 0;
 158         }
 159     }
 160
 161
 162     /**
 163      * Sets the visible part of the list from the reference position.
 164      *
 165      * @param   position    Reference position previously returned by {@link LocalFileListFragment#getReferencePosition()}
 166      */
 167     protected void setReferencePosition(int position) {
 168         if (mList != null) {
 169             mList.setAndCenterSelection(position);
 170         }
 171     }
 172
 173
 174     /*
 175      * Restore index and position
 176      */
 177     protected void restoreIndexAndTopPosition() {
 178         if (mIndexes.size() > 0) {
 179             // needs to be checked; not every browse-up had a browse-down before
 180
 181             int index = mIndexes.remove(mIndexes.size() - 1);
 182
 183             int firstPosition = mFirstPositions.remove(mFirstPositions.size() -1);
 184
 185             int top = mTops.remove(mTops.size() - 1);
 186
 187             mList.setSelectionFromTop(firstPosition, top);
 188
 189             // Move the scroll if the selection is not visible
 190             int indexPosition = mHeightCell*index;
 191             int height = mList.getHeight();
 192
 193             if (indexPosition > height) {
 194                 if (android.os.Build.VERSION.SDK_INT >= 11)
 195                 {
 196                     mList.smoothScrollToPosition(index);
 197                 }
 198                 else if (android.os.Build.VERSION.SDK_INT >= 8)
 199                 {
 200                     mList.setSelectionFromTop(index, 0);
 201                 }
 202
 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 = mList.getFirstVisiblePosition();
 215         mFirstPositions.add(firstPosition);
 216
 217         View view = mList.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(SwipeRefreshLayout.OnRefreshListener 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 }