ResourceProxyImpl.java

package org.mozilla.osmdroid.util;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.Drawable;

import org.mozilla.osmdroid.DefaultResourceProxyImpl;

import java.lang.reflect.Field;

/**
 * This is an extension of {@link org.mozilla.osmdroid.DefaultResourceProxyImpl}
 * that first tries to get from resources by using reflection to get the id of the resource
 * from the package that the context is in.
 */
public class ResourceProxyImpl extends DefaultResourceProxyImpl {

    private final Resources mResources;
    private final String mResourceNameBase;

    public ResourceProxyImpl(final Context aContext) {
        super(aContext);
        mResources = aContext.getResources();
        mResourceNameBase = aContext.getPackageName() + ".R$";
    }

    @Override
    public String getString(final string pResId) {
        final int id = getId("string", pResId.name());
        return id != 0 ? mResources.getString(id) : super.getString(pResId);
    }

    @Override
    public String getString(final string pResId, final Object... formatArgs) {
        final int id = getId("string", pResId.name());
        return id != 0 ? mResources.getString(id, formatArgs) : super.getString(pResId, formatArgs);
    }

    @Override
    public Bitmap getBitmap(final bitmap pResId) {
        final int id = getId("drawable", pResId.name());
        return id != 0 ? BitmapFactory.decodeResource(mResources, id) : super.getBitmap(pResId);
    }

    @Override
    public Drawable getDrawable(final bitmap pResId) {
        final int id = getId("drawable", pResId.name());
        return id != 0 ? mResources.getDrawable(id) : super.getDrawable(pResId);
    }

    private int getId(final String aType, final String aName) {
        try {
            final Class<?> cls = Class.forName(mResourceNameBase + aType);
            final Field field = cls.getDeclaredField(aName);
            return field.getInt(null);
        } catch (final Exception e) {
            return 0;
        }
    }
}