vtm/src/org/oscim/overlay/DefaultResourceProxyImpl.java

/*
 * Copyright 2012 osmdroid
 * Copyright 2013 OpenScienceMap
 *
 * This program is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with
 * this program. If not, see <http://www.gnu.org/licenses/>.
 */
package org.oscim.overlay;

import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Field;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.util.DisplayMetrics;

public class DefaultResourceProxyImpl implements ResourceProxy, MapViewConstants {
	//	private static final String TAG = DefaultResourceProxyImpl.class.getSimpleName();

	private DisplayMetrics mDisplayMetrics;

	/**
	 * Constructor.
	 *
	 * @param pContext
	 *            Used to get the display metrics that are used for scaling the
	 *            bitmaps returned by {@@link getBitmap}. Can be null,
	 *            in which case the bitmaps are not scaled.
	 */
	public DefaultResourceProxyImpl(final Context pContext) {
		if (pContext != null) {
			mDisplayMetrics = pContext.getResources().getDisplayMetrics();
			// if (DEBUGMODE) {
			// logger.debug("mDisplayMetrics=" + mDisplayMetrics);
			// }
		}
	}

	@Override
	public String getString(final string pResId) {
		switch (pResId) {
			case mapnik:
				return "Mapnik";
			case cyclemap:
				return "Cycle Map";
			case public_transport:
				return "Public transport";
			case base:
				return "OSM base layer";
			case topo:
				return "Topographic";
			case hills:
				return "Hills";
			case cloudmade_standard:
				return "CloudMade (Standard tiles)";
			case cloudmade_small:
				return "CloudMade (small tiles)";
			case mapquest_osm:
				return "Mapquest";
			case mapquest_aerial:
				return "Mapquest Aerial";
			case bing:
				return "Bing";
			case fiets_nl:
				return "OpenFietsKaart overlay";
			case base_nl:
				return "Netherlands base overlay";
			case roads_nl:
				return "Netherlands roads overlay";
			case unknown:
				return "Unknown";
			case format_distance_meters:
				return "%s m";
			case format_distance_kilometers:
				return "%s km";
			case format_distance_miles:
				return "%s mi";
			case format_distance_nautical_miles:
				return "%s nm";
			case format_distance_feet:
				return "%s ft";
			case online_mode:
				return "Online mode";
			case offline_mode:
				return "Offline mode";
			case my_location:
				return "My location";
			case compass:
				return "Compass";
			case map_mode:
				return "Map mode";
			default:
				throw new IllegalArgumentException();
		}
	}

	@Override
	public String getString(final string pResId, final Object... formatArgs) {
		return String.format(getString(pResId), formatArgs);
	}

	@Override
	public Bitmap getBitmap(final bitmap pResId) {
		InputStream is = null;
		try {
			final String resName = pResId.name() + ".png";
			is = getClass().getResourceAsStream(resName);
			if (is == null) {
				throw new IllegalArgumentException("Resource not found: " + resName);
			}
			BitmapFactory.Options options = null;
			if (mDisplayMetrics != null) {
				options = getBitmapOptions();
			}
			return BitmapFactory.decodeStream(is, null, options);
		} catch (final OutOfMemoryError e) {
			// logger.error("OutOfMemoryError getting bitmap resource: " +
			// pResId);
			System.gc();
			// there's not much we can do here
			// - when we load a bitmap from resources we expect it to be found
			throw e;
		} finally {
			if (is != null) {
				try {
					is.close();
				} catch (final IOException ignore) {
				}
			}
		}
	}

	private BitmapFactory.Options getBitmapOptions() {
		try {
			final Field density = DisplayMetrics.class.getDeclaredField("DENSITY_DEFAULT");
			final Field inDensity = BitmapFactory.Options.class.getDeclaredField("inDensity");
			final Field inTargetDensity = BitmapFactory.Options.class
					.getDeclaredField("inTargetDensity");
			final Field targetDensity = DisplayMetrics.class.getDeclaredField("densityDpi");
			final BitmapFactory.Options options = new BitmapFactory.Options();
			inDensity.setInt(options, density.getInt(null));
			inTargetDensity.setInt(options, targetDensity.getInt(mDisplayMetrics));
			return options;
		} catch (final IllegalAccessException ex) {
			// ignore
		} catch (final NoSuchFieldException ex) {
			// ignore
		}
		return null;
	}

	@Override
	public Drawable getDrawable(final bitmap pResId) {
		return new BitmapDrawable(getBitmap(pResId));
	}

	@Override
	public float getDisplayMetricsDensity() {
		return mDisplayMetrics.density;
	}

}