Question

我是Android开发的新手。我正在尝试做多个多边形。我做到了，但是第二个多边形从第一个多边形的末端开始。我列出了我关注的问题以及显示我的结果的图像。

这是我的代码：

public class MainActivity extends AppCompatActivity implements OnMapReadyCallback {

    private GoogleMap mMap;
    private static final LatLng MainLocation = new LatLng(40.828070, -111.904610);
    FrameLayout fram_map;
    FloatingActionButton fab;
    Boolean Is_MAP_Moveable = false;
    Projection projection;
    public double latitude;
    public double longitude;
    PolygonOptions rectOptions;
    ArrayList < LatLng > val = new ArrayList < > ();
    ArrayList < ArrayList < LatLng >> val2 = new ArrayList < > ();
    Polygon polygon;
    String LogName = "XEL";

    @SuppressLint("ClickableViewAccessibility")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);
        fram_map = (FrameLayout) findViewById(R.id.fram_map);
        fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (Is_MAP_Moveable) {
                    Is_MAP_Moveable = false;
                    if (val2.isEmpty()) {
                        val2.add(0, val);
                    } else {
                        val2.add(val2.size(), val);
                    }

                } else {
                    Is_MAP_Moveable = true;
                }
            }
        });
        fram_map.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                if (Is_MAP_Moveable) {
                    float x = event.getX();
                    float y = event.getY();

                    int x_co = Math.round(x);
                    int y_co = Math.round(y);

                    projection = mMap.getProjection();
                    Point x_y_points = new Point(x_co, y_co);

                    LatLng latLng = mMap.getProjection().fromScreenLocation(x_y_points);
                    latitude = latLng.latitude;

                    longitude = latLng.longitude;

                    int eventaction = event.getAction();
                    switch (eventaction) {
                        case MotionEvent.ACTION_DOWN:
                            val.add(new LatLng(latitude, longitude));
                        case MotionEvent.ACTION_MOVE:
                            val.add(new LatLng(latitude, longitude));
                        case MotionEvent.ACTION_UP:
                            Draw_Map();
                            break;
                    }

                } else {
                    Toast.makeText(MainActivity.this, "Please start the zone", Toast.LENGTH_SHORT).show();
                }

                return Is_MAP_Moveable;

            }
        });
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
        mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
        googleMap.setOnPolygonClickListener(new GoogleMap.OnPolygonClickListener() {
            @Override
            public void onPolygonClick(Polygon polygon) {
                Toast.makeText(MainActivity.this, polygon.getPoints().toString(), Toast.LENGTH_SHORT).show();
            }
        });
        googleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(MainLocation,
            20));
    }

    public void Draw_Map() {
        /*  for (int i = 0; i < val2.size(); i++) {
              rectOptions = new PolygonOptions();
              rectOptions.addAll(val2.get(i));
              rectOptions.strokeColor(Color.BLUE);
              rectOptions.strokeWidth(7);
              rectOptions.fillColor(Color.CYAN);
              polygon = mMap.addPolygon(rectOptions);
              polygon.setClickable(true);
          }*/
        rectOptions = new PolygonOptions();
        rectOptions.addAll(val);
        rectOptions.strokeColor(Color.BLUE);
        rectOptions.strokeWidth(7);
        rectOptions.fillColor(Color.CYAN);
        polygon = mMap.addPolygon(rectOptions);
        polygon.setClickable(true);
    }
}

Answer 1

从概述上，我可以提出几点建议。如果您执行这些操作，则可能会解决该问题：

现在是否要使用单独的onClick。使用onTouch。

//declare globally
float init_x, init_y;
float tolerance = 5;

fram_map.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    init_x = event.getX();
                    init_y = event.getY();
                    break;
                case MotionEvent.ACTION_MOVE:

                    break;
                case MotionEvent.ACTION_UP:
                    float x = event.getX();
                    float y = event.getY();
                    Is_MAP_Moveable = Math.abs(init_x - x) > tolerance || Math.abs(init_y - y) > tolerance;
                    if(!Is_MAP_Moveable) {
                        int x_co = Math.round(x);
                        int y_co = Math.round(y);

                        projection = mMap.getProjection();
                        Point x_y_points = new Point(x_co, y_co);
                        LatLng latLng = mMap.getProjection().fromScreenLocation(x_y_points);
                        latitude = latLng.latitude;
                        longitude = latLng.longitude;
                        val.add(new LatLng(latitude, longitude));
                        Draw_Map();
                    } else {
                        Toast.makeText(MainActivity.this, "Please start the zone", Toast.LENGTH_SHORT).show();
                    }
                    break;
            }
            return Is_MAP_Moveable;

        }
    });

不需要使用LatLng-val2的ArrayList中的ArrayList。使用val绘制多边形。
在合并任何新多边形之前，请清除地图上的所有多边形，因为您要推送ArrayList中的元素。添加新的多边形之前，请先使用polygon.remove();。

Google Maps多个多边形从第二个多边形从第一个多边形的位置开始

1 个答案: