PolygonDrawController.java 文件源码

@Override
protected void updateTempLineAfterMove(MouseEvent<?> event) {
    if (tempPolygon == null) {
        updateTempLineAfterClick();
    }

    Polygon polygon = (Polygon) geometry;

    if (polygon != null && polygon.getCoordinates() != null && polygon.getCoordinates().length > 0) {

        LinearRing ring = geometry.getGeometryFactory().createLinearRing(polygon.getCoordinates());
        if (ring != null && geometry.getCoordinates().length > 0) {

            Coordinate[] coordinates = ring.getCoordinates();
            Coordinate firstCoordinate = coordinates[0];
            Coordinate lastCoordinate = coordinates[coordinates.length - 2];

            LineString lineStringPan = geometry.getGeometryFactory().createLineString(new Coordinate[] {
                            getTransformer().worldToPan(lastCoordinate),
                            getPanPosition(event),
                            getTransformer().worldToPan(firstCoordinate) });
            tempLine.setGeometry(lineStringPan);

            mapWidget.render(tempLine, RenderGroup.VECTOR, RenderStatus.ALL);
        }
    }
}