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/* * Copyright (C) 2011 Google Inc. * Licensed to The Android Open Source Project. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* ========================================================================== *HISTORY * *Tag Date Author Description *============== ============ =============== ============================== *CONFLICT-50001 2014/10/23 zhaotianyong Modify the package conflict ============================================================================ */ package com.tct.fw.ex.photo.adapters; import android.content.Context; import android.database.Cursor; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.util.Log; import android.util.SparseIntArray; import android.view.View; //TS: MOD by zhaotianyong for CONFLICT_50001 START //import com.tct.ex.photo.provider.PhotoContract; import com.tct.fw.ex.photo.provider.PhotoContract; //TS: MOD by zhaotianyong for CONFLICT_50001 END import java.util.HashMap; /** * Page adapter for use with an BaseCursorLoader. Unlike other cursor adapters, this has no * observers for automatic refresh. Instead, it depends upon external mechanisms to provide * the update signal. */ public abstract class BaseCursorPagerAdapter extends BaseFragmentPagerAdapter { private static final String TAG = "BaseCursorPagerAdapter"; protected Context mContext; protected Cursor mCursor; protected int mRowIDColumn; /** Mapping of row ID to cursor position */ protected SparseIntArray mItemPosition; /** Mapping of instantiated object to row ID */ protected final HashMap<Object, Integer> mObjectRowMap = new HashMap<Object, Integer>(); /** * Constructor that always enables auto-requery. * * @param c The cursor from which to get the data. * @param context The context */ public BaseCursorPagerAdapter(Context context, FragmentManager fm, Cursor c) { super(fm); init(context, c); } /** * Makes a fragment for the data pointed to by the cursor * * @param context Interface to application's global information * @param cursor The cursor from which to get the data. The cursor is already * moved to the correct position. * @return the newly created fragment. */ public abstract Fragment getItem(Context context, Cursor cursor, int position); // TODO: This shouldn't just return null - maybe it needs to wait for a cursor to be supplied? // See b/7103023 @Override public Fragment getItem(int position) { if (mCursor != null && moveCursorTo(position)) { return getItem(mContext, mCursor, position); } return null; } @Override public int getCount() { if (mCursor != null) { return mCursor.getCount(); } else { return 0; } } @Override public Object instantiateItem(View container, int position) { if (mCursor == null) { throw new IllegalStateException("this should only be called when the cursor is valid"); } final Integer rowId; if (moveCursorTo(position)) { rowId = mCursor.getString(mRowIDColumn).hashCode(); } else { rowId = null; } // Create the fragment and bind cursor data final Object obj = super.instantiateItem(container, position); if (obj != null) { mObjectRowMap.put(obj, rowId); } return obj; } @Override public void destroyItem(View container, int position, Object object) { mObjectRowMap.remove(object); super.destroyItem(container, position, object); } @Override public int getItemPosition(Object object) { final Integer rowId = mObjectRowMap.get(object); if (rowId == null || mItemPosition == null) { return POSITION_NONE; } final int position = mItemPosition.get(rowId, POSITION_NONE); return position; } /** * @return true if data is valid */ public boolean isDataValid() { return mCursor != null; } /** * Returns the cursor. */ public Cursor getCursor() { return mCursor; } /** * Returns the data item associated with the specified position in the data set. */ public Object getDataItem(int position) { if (mCursor != null && moveCursorTo(position)) { return mCursor; } else { return null; } } /** * Returns the row id associated with the specified position in the list. */ public long getItemId(int position) { if (mCursor != null && moveCursorTo(position)) { return mCursor.getString(mRowIDColumn).hashCode(); } else { return 0; } } /** * Swap in a new Cursor, returning the old Cursor. * * @param newCursor The new cursor to be used. * @return Returns the previously set Cursor, or null if there was not one. * If the given new Cursor is the same instance is the previously set * Cursor, null is also returned. */ public Cursor swapCursor(Cursor newCursor) { if (Log.isLoggable(TAG, Log.VERBOSE)) { Log.v(TAG, "swapCursor old=" + (mCursor == null ? -1 : mCursor.getCount()) + "; new=" + (newCursor == null ? -1 : newCursor.getCount())); } if (newCursor == mCursor) { return null; } Cursor oldCursor = mCursor; mCursor = newCursor; if (newCursor != null) { mRowIDColumn = newCursor.getColumnIndex(PhotoContract.PhotoViewColumns.URI); } else { mRowIDColumn = -1; } setItemPosition(); notifyDataSetChanged(); // notify the observers about the new cursor return oldCursor; } /** * Converts the cursor into a CharSequence. Subclasses should override this * method to convert their results. The default implementation returns an * empty String for null values or the default String representation of * the value. * * @param cursor the cursor to convert to a CharSequence * @return a CharSequence representing the value */ public CharSequence convertToString(Cursor cursor) { return cursor == null ? "" : cursor.toString(); } @Override protected String makeFragmentName(int viewId, int index) { if (moveCursorTo(index)) { return "android:pager:" + viewId + ":" + mCursor.getString(mRowIDColumn).hashCode(); } else { return super.makeFragmentName(viewId, index); } } /** * Moves the cursor to the given position * * @return {@code true} if the cursor's position was set. Otherwise, {@code false}. */ private boolean moveCursorTo(int position) { if (mCursor != null && !mCursor.isClosed()) { return mCursor.moveToPosition(position); } return false; } /** * Initialize the adapter. */ private void init(Context context, Cursor c) { boolean cursorPresent = c != null; mCursor = c; mContext = context; mRowIDColumn = cursorPresent ? mCursor.getColumnIndex(PhotoContract.PhotoViewColumns.URI) : -1; } /** * Sets the {@link #mItemPosition} instance variable with the current mapping of * row id to cursor position. */ private void setItemPosition() { if (mCursor == null || mCursor.isClosed()) { mItemPosition = null; return; } SparseIntArray itemPosition = new SparseIntArray(mCursor.getCount()); mCursor.moveToPosition(-1); while (mCursor.moveToNext()) { final int rowId = mCursor.getString(mRowIDColumn).hashCode(); final int position = mCursor.getPosition(); itemPosition.append(rowId, position); } mItemPosition = itemPosition; } }