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.ui.ExtendedListView;
  38 import com.owncloud.android.utils.Log_OC;
  39
  40 /**
  41  *  TODO extending SherlockListFragment instead of SherlockFragment
  42  */
  43 public class ExtendedListFragment extends SherlockFragment
  44 implements OnItemClickListener, SwipeRefreshLayout.OnRefreshListener {
  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 SwipeRefreshLayout.OnRefreshListener mOnRefreshListener = null;
  68
  69     private GridView imageView;
  70     private View fileView;
  71
  72
  73     public void setListAdapter(ListAdapter listAdapter) {
  74         imageView.setAdapter(listAdapter);
  75         imageView.invalidate();
  76     }
  77
  78     public ListView getListView() {
  79         return mList;
  80     }
  81
  82     protected void switchImageView(){
  83         // TODO berechnen, wieviele Spalten
  84         imageView.setNumColumns(3);
  85         mList.invalidate();
  86        imageView.invalidate();
  87     }
  88
  89     protected void switchFileView(){
  90         imageView.setNumColumns(1);
  91         mList.invalidate();
  92        imageView.invalidate();
  93     }
  94
  95
  96     @Override
  97     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
  98         Log_OC.e(TAG, "onCreateView");
  99
 100         View v = inflater.inflate(R.layout.list_fragment, null);
 101
 102         imageView = (GridView) v.findViewById(R.id.grid_list_view);
 103         imageView.setOnItemClickListener(this);
 104
 105        // mEmptyListMessage = (TextView) v.findViewById(R.id.empty_list_view);
 106         mList = (ExtendedListView)(v.findViewById(R.id.list_root));
 107         // mList.setOnItemClickListener(this);
 108
 109         mList.setDivider(getResources().getDrawable(R.drawable.uploader_list_separator));
 110         mList.setDividerHeight(1);
 111
 112         if (savedInstanceState != null) {
 113             int referencePosition = savedInstanceState.getInt(KEY_SAVED_LIST_POSITION);
 114             setReferencePosition(referencePosition);
 115         }
 116
 117         // Pull down refresh
 118         mRefreshLayout = (SwipeRefreshLayout) v.findViewById(R.id.swipe_refresh_files);
 119         mRefreshEmptyLayout = (SwipeRefreshLayout) v.findViewById(R.id.swipe_refresh_files_emptyView);
 120
 121         onCreateSwipeToRefresh(mRefreshLayout);
 122         onCreateSwipeToRefresh(mRefreshEmptyLayout);
 123
 124         mList.setEmptyView(mRefreshEmptyLayout);
 125
 126         return v;
 127     }
 128
 129
 130     /**
 131      * {@inheritDoc}
 132      */
 133     @Override
 134     public void onActivityCreated(Bundle savedInstanceState) {
 135         super.onActivityCreated(savedInstanceState);
 136
 137         if (savedInstanceState != null) {
 138             mIndexes = savedInstanceState.getIntegerArrayList(KEY_INDEXES);
 139             mFirstPositions = savedInstanceState.getIntegerArrayList(KEY_FIRST_POSITIONS);
 140             mTops = savedInstanceState.getIntegerArrayList(KEY_TOPS);
 141             mHeightCell = savedInstanceState.getInt(KEY_HEIGHT_CELL);
 142             setMessageForEmptyList(savedInstanceState.getString(KEY_EMPTY_LIST_MESSAGE));
 143
 144         } else {
 145             mIndexes = new ArrayList<Integer>();
 146             mFirstPositions = new ArrayList<Integer>();
 147             mTops = new ArrayList<Integer>();
 148             mHeightCell = 0;
 149         }
 150     }
 151
 152
 153     @Override
 154     public void onSaveInstanceState(Bundle savedInstanceState) {
 155         super.onSaveInstanceState(savedInstanceState);
 156         Log_OC.e(TAG, "onSaveInstanceState()");
 157         savedInstanceState.putInt(KEY_SAVED_LIST_POSITION, getReferencePosition());
 158         savedInstanceState.putIntegerArrayList(KEY_INDEXES, mIndexes);
 159         savedInstanceState.putIntegerArrayList(KEY_FIRST_POSITIONS, mFirstPositions);
 160         savedInstanceState.putIntegerArrayList(KEY_TOPS, mTops);
 161         savedInstanceState.putInt(KEY_HEIGHT_CELL, mHeightCell);
 162         savedInstanceState.putString(KEY_EMPTY_LIST_MESSAGE, getEmptyViewText());
 163     }
 164
 165
 166     /**
 167      * Calculates the position of the item that will be used as a reference to reposition the visible items in the list when
 168      * the device is turned to other position.
 169      *
 170      * THe current policy is take as a reference the visible item in the center of the screen.
 171      *
 172      * @return      The position in the list of the visible item in the center of the screen.
 173      */
 174     protected int getReferencePosition() {
 175         if (mList != null) {
 176             return (mList.getFirstVisiblePosition() + mList.getLastVisiblePosition()) / 2;
 177         } else {
 178             return 0;
 179         }
 180     }
 181
 182
 183     /**
 184      * Sets the visible part of the list from the reference position.
 185      *
 186      * @param   position    Reference position previously returned by {@link LocalFileListFragment#getReferencePosition()}
 187      */
 188     protected void setReferencePosition(int position) {
 189         if (mList != null) {
 190             mList.setAndCenterSelection(position);
 191         }
 192     }
 193
 194
 195     /*
 196      * Restore index and position
 197      */
 198     protected void restoreIndexAndTopPosition() {
 199         if (mIndexes.size() > 0) {
 200             // needs to be checked; not every browse-up had a browse-down before
 201
 202             int index = mIndexes.remove(mIndexes.size() - 1);
 203
 204             int firstPosition = mFirstPositions.remove(mFirstPositions.size() -1);
 205
 206             int top = mTops.remove(mTops.size() - 1);
 207
 208             mList.setSelectionFromTop(firstPosition, top);
 209
 210             // Move the scroll if the selection is not visible
 211             int indexPosition = mHeightCell*index;
 212             int height = mList.getHeight();
 213
 214             if (indexPosition > height) {
 215                 if (android.os.Build.VERSION.SDK_INT >= 11)
 216                 {
 217                     mList.smoothScrollToPosition(index);
 218                 }
 219                 else if (android.os.Build.VERSION.SDK_INT >= 8)
 220                 {
 221                     mList.setSelectionFromTop(index, 0);
 222                 }
 223
 224             }
 225         }
 226     }
 227
 228     /*
 229      * Save index and top position
 230      */
 231     protected void saveIndexAndTopPosition(int index) {
 232
 233         mIndexes.add(index);
 234
 235         int firstPosition = mList.getFirstVisiblePosition();
 236         mFirstPositions.add(firstPosition);
 237
 238         View view = mList.getChildAt(0);
 239         int top = (view == null) ? 0 : view.getTop() ;
 240
 241         mTops.add(top);
 242
 243         // Save the height of a cell
 244         mHeightCell = (view == null || mHeightCell != 0) ? mHeightCell : view.getHeight();
 245     }
 246
 247
 248     @Override
 249     public void onItemClick (AdapterView<?> parent, View view, int position, long id) {
 250         // to be @overriden
 251     }
 252
 253     @Override
 254     public void onRefresh() {
 255         // to be @overriden
 256         mRefreshLayout.setRefreshing(false);
 257         mRefreshEmptyLayout.setRefreshing(false);
 258
 259         if (mOnRefreshListener != null) {
 260             mOnRefreshListener.onRefresh();
 261         }
 262     }
 263
 264     public void setOnRefreshListener(SwipeRefreshLayout.OnRefreshListener listener) {
 265         mOnRefreshListener = listener;
 266     }
 267
 268
 269     /**
 270      * Enables swipe gesture
 271      */
 272     public void enableSwipe() {
 273         mRefreshLayout.setEnabled(true);
 274     }
 275
 276     /**
 277      * Disables swipe gesture. It prevents manual gestures but keeps the option you show
 278      * refreshing programmatically.
 279      */
 280     public void disableSwipe() {
 281         mRefreshLayout.setEnabled(false);
 282     }
 283
 284     /**
 285      * It shows the SwipeRefreshLayout progress
 286      */
 287     public void showSwipeProgress() {
 288         mRefreshLayout.setRefreshing(true);
 289     }
 290
 291     /**
 292      * It shows the SwipeRefreshLayout progress
 293      */
 294     public void hideSwipeProgress() {
 295         mRefreshLayout.setRefreshing(false);
 296     }
 297
 298     /**
 299      * Set message for empty list view
 300      */
 301     public void setMessageForEmptyList(String message) {
 302         if (mEmptyListMessage != null) {
 303             mEmptyListMessage.setText(message);
 304         }
 305     }
 306
 307     /**
 308      * Get the text of EmptyListMessage TextView
 309      *
 310      * @return String
 311      */
 312     public String getEmptyViewText() {
 313         return (mEmptyListMessage != null) ? mEmptyListMessage.getText().toString() : "";
 314     }
 315
 316     private void onCreateSwipeToRefresh(SwipeRefreshLayout refreshLayout) {
 317         // Colors in animations: background
 318         refreshLayout.setColorScheme(R.color.background_color, R.color.background_color, R.color.background_color,
 319                 R.color.background_color);
 320
 321         refreshLayout.setOnRefreshListener(this);
 322     }
 323
 324 }