android - 如何在android中打印多个位置的谷歌地图

Question

onCreate 方法:

{
        double[] lat = {24.8926596, 48.85837, 0};
        double[] lang = {67.0835093, 2.294481, 0};
        List<CustomberLatLang> list = new ArrayList<CustomberLatLang>();
        CustomberLatLang datamodel = new CustomberLatLang();
        for (int i = 0; i < lat.length; i++) {
            datamodel.setLat(lat[i]);
            datamodel.setLang(lang[i]);
            list.add(datamodel);

        }
        insertMarkers(list);
}

insertMarkers 方法:

 private void insertMarkers(List<CustomberLatLang> list) {
        final LatLngBounds.Builder builder = new LatLngBounds.Builder();

        for (int i = 0; i < list.size(); i++) {
            final LatLng position = new LatLng(list.get(i).getLat(), list.get(i).getLang());
            final MarkerOptions options = new MarkerOptions().position(position);

            map.addMarker(options);

            builder.include(position);
        }

    }

数据模型:

public class CustomberLatLang {

    double lat;
    double lang;

    public double getLat() {
        return lat;
    }

    public void setLat(double lat) {
        this.lat = lat;
    }

    public double getLang() {
        return lang;
    }

    public void setLang(double lang) {
        this.lang = lang;
    }
}

我正在尝试设置所有位置谷歌地图的标记。当我尝试运行我的代码时，我得到了 nullpointer exception map.addMarker(options);

Answer 1

您的 map 变量为空。尝试在使用前初始化此变量。

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    ...

    map = fm.getMap();

    ...
    insertMarkers(list);