HistoryExpandableListAdapter.java

/*
 * Zirco Browser for Android
 * 
 * Copyright (C) 2010 - 2011 J. Devauchelle and contributors.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 3 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

package org.shadowsocks.zirco.model.adapters;

import org.shadowsocks.R;
import org.shadowsocks.zirco.model.items.HistoryItem;

import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.drawable.BitmapDrawable;
import android.provider.BaseColumns;
import android.provider.Browser;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.DateSorter;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

/**
 * Custom adapter for displaying history, splitted in bins. Adapted from:
 * https:/
 * /github.com/CyanogenMod/android_packages_apps_Browser/blob/gingerbread/
 * src/com/android/browser/BrowserHistoryPage.java
 * http://grepcode.com/file/repository
 * .grepcode.com/java/ext/com.google.android/android
 * -apps/2.2_r1.1/com/android/browser
 * /DateSortedExpandableListAdapter.java/?v=source
 */
public class HistoryExpandableListAdapter extends BaseExpandableListAdapter {

	private LayoutInflater mInflater = null;

	private int[] mItemMap;
	private int mNumberOfBins;
	private int mIdIndex;
	private DateSorter mDateSorter;

	private Context mContext;
	private Cursor mCursor;
	private int mDateIndex;

	private int mFaviconSize;

	/**
	 * Constructor.
	 * 
	 * @param context
	 *            The current context.
	 * @param cursor
	 *            The data cursor.
	 * @param dateIndex
	 *            The date index ?
	 */
	public HistoryExpandableListAdapter(Context context, Cursor cursor,
			int dateIndex, int faviconSize) {
		mContext = context;
		mCursor = cursor;
		mDateIndex = dateIndex;
		mFaviconSize = faviconSize;

		mDateSorter = new DateSorter(mContext);
		mIdIndex = cursor.getColumnIndexOrThrow(BaseColumns._ID);

		mInflater = (LayoutInflater) mContext
				.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

		buildMap();
	}

	/**
	 * Split the data in the cursor into several "bins": today, yesterday, last
	 * 7 days, last month, older.
	 */
	private void buildMap() {
		int[] array = new int[DateSorter.DAY_COUNT];
		// Zero out the array.
		for (int j = 0; j < DateSorter.DAY_COUNT; j++) {
			array[j] = 0;
		}

		mNumberOfBins = 0;
		int dateIndex = -1;
		if (mCursor.moveToFirst() && mCursor.getCount() > 0) {
			while (!mCursor.isAfterLast()) {
				long date = getLong(mDateIndex);
				int index = mDateSorter.getIndex(date);
				if (index > dateIndex) {
					mNumberOfBins++;
					if (index == DateSorter.DAY_COUNT - 1) {
						// We are already in the last bin, so it will
						// include all the remaining items
						array[index] = mCursor.getCount()
								- mCursor.getPosition();
						break;
					}
					dateIndex = index;
				}
				array[dateIndex]++;
				mCursor.moveToNext();
			}
		}

		mItemMap = array;
	}

	@Override
	public Object getChild(int groupPosition, int childPosition) {
		moveCursorToChildPosition(groupPosition, childPosition);

		String title = mCursor
				.getString(Browser.HISTORY_PROJECTION_TITLE_INDEX);
		if (title.length() > 11)
			title = title.substring(0, 10) + "...";

		return new HistoryItem(
				mCursor.getLong(Browser.HISTORY_PROJECTION_ID_INDEX), title,
				mCursor.getString(Browser.HISTORY_PROJECTION_URL_INDEX),
				mCursor.getBlob(Browser.HISTORY_PROJECTION_FAVICON_INDEX));
	}

	@Override
	public long getChildId(int groupPosition, int childPosition) {
		if (moveCursorToChildPosition(groupPosition, childPosition)) {
			return getLong(mIdIndex);
		}
		return 0;
	}

	@Override
	public int getChildrenCount(int groupPosition) {
		return mItemMap[groupPositionToBin(groupPosition)];
	}

	@Override
	public View getChildView(int groupPosition, int childPosition,
			boolean isLastChild, View convertView, ViewGroup parent) {
		View view = getCustomChildView();

		TextView titleView = (TextView) view
				.findViewById(R.id.HistoryRow_Title);

		HistoryItem item = (HistoryItem) getChild(groupPosition, childPosition);
		titleView.setText(item.getTitle());

		TextView urlView = (TextView) view.findViewById(R.id.HistoryRow_Url);
		urlView.setText(item.getUrl());

		ImageView faviconView = (ImageView) view
				.findViewById(R.id.HistoryRow_Thumbnail);
		Bitmap favicon = item.getFavicon();
		if (favicon != null) {
			BitmapDrawable icon = new BitmapDrawable(favicon);

			Bitmap bm = Bitmap.createBitmap(mFaviconSize, mFaviconSize,
					Bitmap.Config.ARGB_4444);
			Canvas canvas = new Canvas(bm);

			icon.setBounds(0, 0, mFaviconSize, mFaviconSize);
			icon.draw(canvas);

			faviconView.setImageBitmap(bm);
			// faviconView.setImageBitmap(item.getFavicon());
		} else {
			faviconView.setImageResource(R.drawable.fav_icn_unknown);
		}

		return view;
	}

	/**
	 * Create a new child view.
	 * 
	 * @return The created view.
	 */
	private View getCustomChildView() {
		LinearLayout view = (LinearLayout) mInflater.inflate(
				R.layout.history_row, null, false);

		return view;
	}

	/**
	 * Create a new view.
	 * 
	 * @return The created view.
	 */
	private TextView getGenericView() {
		// Layout parameters for the ExpandableListView
		AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
				ViewGroup.LayoutParams.FILL_PARENT, (int) (45 * mContext
						.getResources().getDisplayMetrics().density));

		TextView textView = new TextView(mContext);
		textView.setLayoutParams(lp);
		// Center the text vertically
		textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
		// Set the text starting position
		textView.setPadding((int) (35 * mContext.getResources()
				.getDisplayMetrics().density), 0, 0, 0);
		return textView;
	}

	@Override
	public Object getGroup(int groupPosition) {

		int binIndex = groupPositionToBin(groupPosition);

		switch (binIndex) {
		case 0:
			return mContext.getResources().getString(
					R.string.HistoryListActivity_Today);
		case 1:
			return mContext.getResources().getString(
					R.string.HistoryListActivity_Yesterday);
		case 2:
			return mContext.getResources().getString(
					R.string.HistoryListActivity_LastSevenDays);
		case 3:
			return mContext.getResources().getString(
					R.string.HistoryListActivity_LastMonth);
		default:
			return mContext.getResources().getString(
					R.string.HistoryListActivity_Older);
		}
	}

	@Override
	public int getGroupCount() {
		return mNumberOfBins;
	}

	@Override
	public long getGroupId(int groupPosition) {
		return groupPosition;
	}

	@Override
	public View getGroupView(int groupPosition, boolean isExpanded,
			View convertView, ViewGroup parent) {
		TextView textView = getGenericView();
		textView.setText(getGroup(groupPosition).toString());
		return textView;
	}

	/**
	 * Get a long-typed data from mCursor.
	 * 
	 * @param cursorIndex
	 *            The column index.
	 * @return The long data.
	 */
	private long getLong(int cursorIndex) {
		return mCursor.getLong(cursorIndex);
	}

	/**
	 * Translates from a group position in the ExpandableList to a bin. This is
	 * necessary because some groups have no history items, so we do not include
	 * those in the ExpandableList.
	 * 
	 * @param groupPosition
	 *            Position in the ExpandableList's set of groups
	 * @return The corresponding bin that holds that group.
	 */
	private int groupPositionToBin(int groupPosition) {
		if (groupPosition < 0 || groupPosition >= DateSorter.DAY_COUNT) {
			throw new AssertionError("group position out of range");
		}
		if (DateSorter.DAY_COUNT == mNumberOfBins || 0 == mNumberOfBins) {
			// In the first case, we have exactly the same number of bins
			// as our maximum possible, so there is no need to do a
			// conversion
			// The second statement is in case this method gets called when
			// the array is empty, in which case the provided groupPosition
			// will do fine.
			return groupPosition;
		}
		int arrayPosition = -1;
		while (groupPosition > -1) {
			arrayPosition++;
			if (mItemMap[arrayPosition] != 0) {
				groupPosition--;
			}
		}
		return arrayPosition;
	}

	@Override
	public boolean hasStableIds() {
		return true;
	}

	@Override
	public boolean isChildSelectable(int groupPosition, int childPosition) {
		return true;
	}

	/**
	 * Move the cursor to the record corresponding to the given group position
	 * and child position.
	 * 
	 * @param groupPosition
	 *            The group position.
	 * @param childPosition
	 *            The child position.
	 * @return True if the move has succeeded.
	 */
	private boolean moveCursorToChildPosition(int groupPosition,
			int childPosition) {
		if (mCursor.isClosed()) {
			return false;
		}
		groupPosition = groupPositionToBin(groupPosition);
		int index = childPosition;
		for (int i = 0; i < groupPosition; i++) {
			index += mItemMap[i];
		}
		return mCursor.moveToPosition(index);
	}

	/**
	 * Determine which group an item belongs to.
	 * 
	 * @param childId
	 *            ID of the child view in question.
	 * @return int Group position of the containing group.
	 */
	/*
	 * private int groupFromChildId(long childId) { int group = -1; for
	 * (mCursor.moveToFirst(); !mCursor.isAfterLast(); mCursor.moveToNext()) {
	 * if (getLong(mIdIndex) == childId) { int bin =
	 * mDateSorter.getIndex(getLong(mDateIndex)); // bin is the same as the
	 * group if the number of bins is the // same as DateSorter if
	 * (DateSorter.DAY_COUNT == mNumberOfBins) return bin; // There are some
	 * empty bins. Find the corresponding group. group = 0; for (int i = 0; i <
	 * bin; i++) { if (mItemMap[i] != 0) group++; } break; } } return group; }
	 * 
	 * private boolean moveCursorToPackedChildPosition(long packedPosition) { if
	 * (ExpandableListView.getPackedPositionType(packedPosition) !=
	 * ExpandableListView.PACKED_POSITION_TYPE_CHILD) { return false; } int
	 * groupPosition = ExpandableListView.getPackedPositionGroup(
	 * packedPosition); int childPosition =
	 * ExpandableListView.getPackedPositionChild( packedPosition); return
	 * moveCursorToChildPosition(groupPosition, childPosition); }
	 */

}