ArcGIS for Android SDK添加shapefile文件始终不成功，困扰几天了

问题描述：shapefileTable 始终为null，shpName值为空，geometryType 为unknown，无法加载shapefile

        ShapefileFeatureTable  shapefileTable = new ShapefileFeatureTable(mappath);
        shapefileTable.loadAsync();
        String shpName = shapefileTable.getTableName();//获取shp文件名
        GeometryType geometryType =  shapefileTable.getGeometryType();//获取shp的类型

全文代码

public class MainActivity extends AppCompatActivity {
    String shpRootPath1 = "map/FW_NEW.shp";
    private String shpPath = null;
    private MapView mapview = null;
    private static final int READ_EXTERNAL_STORAGE= 1;//读取文件权限
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mapview  = findViewById(R.id.mapView);
        Button loadShpBtn = findViewById(R.id.loadShp);
        OpenStreetMapLayer openStreetMapLayer = new OpenStreetMapLayer();
        Basemap basemap = new Basemap(openStreetMapLayer);
        ArcGISMap arcGISMap = new ArcGISMap(basemap);
        mapview.setMap(arcGISMap);
        //查看权限
        if (ContextCompat.checkSelfPermission(
                MainActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE)!=PackageManager.PERMISSION_GRANTED){
            ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.READ_EXTERNAL_STORAGE,Manifest.permission.WRITE_EXTERNAL_STORAGE},READ_EXTERNAL_STORAGE);
        }else {
            shpPath = getSDCardPath() + shpRootPath1;
            File file = new File(shpPath);
            if (file.exists()){
                showShapefile(shpPath,mapview);
            }else {
                Toast.makeText(this,"文件不存在",Toast.LENGTH_SHORT).show();
            }
        }
    }

    /**
     * 加载shp文件
     * @param mappath
     * @param mapView
     */
    public void showShapefile(String mappath,MapView mapView) {
        ShapefileFeatureTable  shapefileTable = new ShapefileFeatureTable(mappath);
        shapefileTable.loadAsync();
        String shpName = shapefileTable.getTableName();//获取shp文件名
        GeometryType geometryType =  shapefileTable.getGeometryType();//获取shp的类型
        if (geometryType == GeometryType.UNKNOWN){
            shapefileTable.addDoneLoadingListener(()-> {
                FeatureLayer shapefileLayer = new FeatureLayer(shapefileTable);
                if (shapefileLayer.getFullExtent() != null) {
                    mapView.setViewpointGeometryAsync(shapefileLayer.getFullExtent());
                } else
                {
                    shapefileLayer.addDoneLoadingListener(()->
                            mapView.setViewpointGeometryAsync(shapefileLayer.getFullExtent()));
                }
                SimpleLineSymbol lineSymbol = new SimpleLineSymbol(SimpleLineSymbol.Style.SOLID, R.color.red, 1.0f);
                SimpleFillSymbol fillSymbol = new SimpleFillSymbol(SimpleFillSymbol.Style.NULL, R.color.red, lineSymbol);
                SimpleRenderer renderer = new SimpleRenderer(fillSymbol);
                shapefileLayer.setRenderer(renderer);
                mapView.getMap().getOperationalLayers().add(shapefileLayer);
            });

        }else{
            Toast.makeText(MainActivity.this,"加载失败",Toast.LENGTH_SHORT).show();
        }
    }
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        switch (requestCode){
            case READ_EXTERNAL_STORAGE:
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
                    //开始操作
                    shpPath = getSDCardPath() + shpRootPath1;
                    File file = new File(shpPath);
                    if (file.exists()){
                        showShapefile(shpPath,mapview);
                    }else {
                        System.out.println("不存在");
                    }
                }else{
                    Toast.makeText(this,"你取消了授权",Toast.LENGTH_LONG).show();
                }
                break;
            default:
                break;
        }
    }
    // 获取SD卡路径
    public String getSDCardPath()
    {
        return Environment.getExternalStorageDirectory().getAbsolutePath()
                + File.separator;
    }
}

权限界面

shapefile文件存放路径