PolylineFeature.java

/*
 *  Copyright (C) 2015 Stichting Akvo (Akvo Foundation)
 *
 *  This file is part of Akvo Flow.
 *
 *  Akvo Flow is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  Akvo Flow 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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Akvo Flow.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.akvo.flow.ui.map;

import android.location.Location;

import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Polyline;
import com.google.android.gms.maps.model.PolylineOptions;

import org.akvo.flow.R;
import org.akvo.flow.util.GeoUtil;

public class PolylineFeature extends Feature {
    public static final String GEOMETRY_TYPE = "LineString";

    private Polyline mPolyline;

    public PolylineFeature(GoogleMap map) {
        super(map);
    }

    @Override
    public void addPoint(LatLng point) {
        super.addPoint(point);
        if (mPolyline == null) {
            PolylineOptions polylineOptions = new PolylineOptions();
            polylineOptions.color(mSelected ? STROKE_COLOR_SELECTED : STROKE_COLOR_DEFAULT);
            mPolyline = mMap.addPolyline(polylineOptions);
        }
        mPolyline.setPoints(mPoints);
    }

    @Override
    public void removePoint() {
        super.removePoint();
        mPolyline.setPoints(mPoints);
    }

    @Override
    public void delete() {
        super.delete();
        if (mPolyline != null) {
            mPolyline.remove();
        }
    }

    @Override
    public void invalidate() {
        super.invalidate();
        if (mPolyline != null) {
            mPolyline.setColor(mSelected ? STROKE_COLOR_SELECTED : STROKE_COLOR_DEFAULT);
            mPolyline.setPoints(mPoints);
        }

        // Compute line length
        float length = 0f;
        LatLng previous = null;
        for (LatLng point : mPoints) {
            if (previous != null) {
                float[] distance = new float[1];
                Location.distanceBetween(previous.latitude, previous.longitude, point.latitude, point.longitude, distance);
                length += distance[0];
            }
            previous = point;
        }
        String lengthVal = String.format("%.2f", length);
        mProperties.add(new Property("length", lengthVal, "Length", GeoUtil.getDisplayLength(length)));
    }

    @Override
    public int getTitle() {
        return R.string.geoshape_line;
    }

    @Override
    public String geoGeometryType() {
        return GEOMETRY_TYPE;
    }

    @Override
    public boolean highlightNext(int position) {
        return position > 0; // Never highlight foremost point (no loops)
    }

}