如何在iOS谷歌地图应用程序上定义闭合多边形？

我的应用程序目前允许用户点击任何地方并在那里绘制标记。我想一个封闭的多边形自动绘制时，有两个以上的标记。我如何做到这一点？第一个点和最后一个点应相互连接以创建闭合形状

到目前为止，我的代码绘制了多段线，但没有将其作为多边形闭合：

// polyline setup -> array made of clicked coordinates
[latitudeTappedCoordinates addObject:[NSNumber numberWithFloat:coordinate.latitude]];
[longitudeTappedCoordinates addObject:[NSNumber numberWithFloat:coordinate.longitude]];
GMSMutablePath *rect = [GMSMutablePath path];
CLLocationCoordinate2D event;
for (int i = 0; i <= [longitudeTappedCoordinates count]-1; i++) {
    event.latitude = [[latitudeTappedCoordinates objectAtIndex:i] floatValue];
    event.longitude = [[longitudeTappedCoordinates objectAtIndex:i] floatValue];
    [rect addCoordinate:event];
}

// draw polyline
GMSPolyline *polygon = [GMSPolyline polylineWithPath:rect];

//多段线设置->由单击的坐标组成的数组
[latitudeTappedCoordinates添加对象：[NSNumber numberWithFloat:坐标.纬度]]；
[longitudeTappedCoordinates添加对象：[NSNumber numberWithFloat:坐标.经度]]；
GMSMutablePath*rect=[GMSMutablePath]；
CLLocationCoordinated2D事件；
对于（int i=0；i您是否尝试将第一个坐标添加为最后一个点

// polyline setup -> array made of clicked coordinates
[latitudeTappedCoordinates addObject:[NSNumber numberWithFloat:coordinate.latitude]];
[longitudeTappedCoordinates addObject:[NSNumber numberWithFloat:coordinate.longitude]];
GMSMutablePath *rect = [GMSMutablePath path];
CLLocationCoordinate2D event;
for (int i = 0; i <= [longitudeTappedCoordinates count]-1; i++) {
    event.latitude = [[latitudeTappedCoordinates objectAtIndex:i] floatValue];
    event.longitude = [[longitudeTappedCoordinates objectAtIndex:i] floatValue];
    [rect addCoordinate:event];
}

// add the first point as the last point, to "close" the polygon
event.latitude = [[latitudeTappedCoordinates objectAtIndex:0] floatValue];
event.longitude = [[longitudeTappedCoordinates objectAtIndex:0] floatValue];
[rect addCoordinate:event];

// draw polyline
GMSPolyline *polygon = [GMSPolyline polylineWithPath:rect];

//多段线设置->由单击的坐标组成的数组
[latitudeTappedCoordinates添加对象：[NSNumber numberWithFloat:坐标.纬度]]；
[longitudeTappedCoordinates添加对象：[NSNumber numberWithFloat:坐标.经度]]；
GMSMutablePath*rect=[GMSMutablePath]；
CLLocationCoordinated2D事件；
对于（int i=0；i
然后，您可以将多边形的填充颜色设置为清晰

    - (void)mapView:(GMSMapView *)mapView
    didTapAtCoordinate:(CLLocationCoordinate2D)coordinate {

        if (latitudeTappedCoordinates == nil){
        longitudeTappedCoordinates = [[NSMutableArray alloc] init];
        latitudeTappedCoordinates = [[NSMutableArray alloc] init];
        }
        [latitudeTappedCoordinates addObject:[NSNumber numberWithFloat:coordinate.latitude]];
        [longitudeTappedCoordinates addObject:[NSNumber numberWithFloat:coordinate.longitude]];

    }

调用以下方法在地图上显示多边形：

    -(void)drawPolygon {

     if ([longitudeTappedCoordinates count]>2) {
         GMSMutablePath *rect = [GMSMutablePath path];
         CLLocationCoordinate2D event;

         for (int i = 0; i <= [longitudeTappedCoordinates count]-1; i++) {
             event.latitude = [[latitudeTappedCoordinates objectAtIndex:i] floatValue];
             event.longitude = [[longitudeTappedCoordinates objectAtIndex:i] floatValue];
             [rect addCoordinate:event];
         }
         event.latitude = [[latitudeTappedCoordinates objectAtIndex:0] floatValue];
         event.longitude = [[longitudeTappedCoordinates objectAtIndex:0] floatValue];
         [rect addCoordinate:event];

         GMSPolygon *polygon = [[GMSPolygon alloc] init];
         polygon.path = rect;
         polygon.fillColor = [UIColor colorWithRed:0.25 green:0 blue:0 alpha:0.2f];
         polygon.strokeColor = [UIColor blackColor];
         polygon.strokeWidth = 2;
         polygon.map = _mapView;
    }
    else {
         NSLog(@"Tap again on Map");
    }
}

-（空）绘图多边形{
如果（[longitudeTappedCoordinates count]>2）{
GMSMutablePath*rect=[GMSMutablePath]；
CLLocationCoordinated2D事件；
对于（inti=0；i，在GMS多边形中，第一个点和最后一个点始终是连接的。您只需要以适当的顺序传递所有坐标

- (void)mapView:(GMSMapView *)mapView
    didTapAtCoordinate:(CLLocationCoordinate2D)coordinate {

    if (latitudeTappedCoordinates == nil){
        longitudeTappedCoordinates = [[NSMutableArray alloc] init];
        latitudeTappedCoordinates = [[NSMutableArray alloc] init];
     }
     [latitudeTappedCoordinates addObject:[NSNumber numberWithFloat:coordinate.latitude]];
     [longitudeTappedCoordinates addObject:[NSNumber numberWithFloat:coordinate.longitude]];

    if([longitudeTappedCoordinates count]>2)
     {
        [self drawPolygonOnMap]
      }

}

然后更改polygon.fillColor以检查多边形是否闭合

-(void)drawPolygon {
         GMSMutablePath *rect = [GMSMutablePath path];
         CLLocationCoordinate2D event;

         for (int i = 0; i <= [longitudeTappedCoordinates count]-1; i++) {
             event.latitude = [[latitudeTappedCoordinates objectAtIndex:i] floatValue];
             event.longitude = [[longitudeTappedCoordinates objectAtIndex:i] floatValue];
             [rect addCoordinate:event];
         }
         event.latitude = [[latitudeTappedCoordinates objectAtIndex:0] floatValue];
         event.longitude = [[longitudeTappedCoordinates objectAtIndex:0] floatValue];
         [rect addCoordinate:event];

         GMSPolygon *polygon = [[GMSPolygon alloc] init];
         polygon.path = rect;
         polygon.fillColor = [UIColor grayColor];
         polygon.strokeColor = [UIColor blackColor];
         polygon.strokeWidth = 2;
         polygon.map = _mapView;
}

-（空）绘图多边形{
GMSMutablePath*rect=[GMSMutablePath]；
CLLocationCoordinated2D事件；
对于（int i=0；i）这很酷，但是当它达到3个以上的坐标时：。我怎么能始终保持“关闭”？对不起，我想你已经在将坐标排序为非交叉模式。这是一个完全不同的问题。让我们来讨论一下。答案是“AND AND”在这个问题上，看起来是一个好的、明确的解决方案……你有解决方案吗？
-(void)drawPolygon {
         GMSMutablePath *rect = [GMSMutablePath path];
         CLLocationCoordinate2D event;

         for (int i = 0; i <= [longitudeTappedCoordinates count]-1; i++) {
             event.latitude = [[latitudeTappedCoordinates objectAtIndex:i] floatValue];
             event.longitude = [[longitudeTappedCoordinates objectAtIndex:i] floatValue];
             [rect addCoordinate:event];
         }
         event.latitude = [[latitudeTappedCoordinates objectAtIndex:0] floatValue];
         event.longitude = [[longitudeTappedCoordinates objectAtIndex:0] floatValue];
         [rect addCoordinate:event];

         GMSPolygon *polygon = [[GMSPolygon alloc] init];
         polygon.path = rect;
         polygon.fillColor = [UIColor grayColor];
         polygon.strokeColor = [UIColor blackColor];
         polygon.strokeWidth = 2;
         polygon.map = _mapView;
}