在Google地图上调整大小，拖动和缩放GMSCircle objective-c

Question

Helllo Everyone，在谷歌地图中，​​我需要显示一个圆，用户可以调整大小，缩放并拖动它，之后我需要找到圆的半径和中心纬度和经度。我怎样才能做到这一点？

Answer 1

对于可点击GMSCircle设置

googleMapCircle.tappable = true; 

并实现拖动圈需要添加谷歌地图的didTapOverlay的委托方法：

- (void)mapView: (GMSMapView*)mapView 
didChangeCameraPosition: (GMSCameraPosition*)position 
{ 
    //set GMSCameraPosition to googleMapCircle position 
    googleMapCircle.position=position.target; 

} 

调整大小GMSCircle上滑块值变化 在滑块值更改方法中添加以下代码：

- (IBAction)sliderValueChnage:(id)sender { 

    _slider = (UISlider*)sender; 
    NSLog(@"slider value = %f", _slider.value); 

    int radius=(int)_slider.value; 
    _lblRadius.text=[NSString stringWithFormat:@"%d m",radius]; 


//For achieve circle radius increase or decrease properly ,first clear map view 
    [_googleMap clear]; 

//Set centre coordinate where you want to draw circle 
CLLocationCoordinate2D circleCenter = CLLocationCoordinate2DMake(_locationManager.location.coordinate.latitude, _locationManager.location.coordinate.longitude); 

// Draw circle on google map 
    GMSCircle *googleMapCircle = [GMSCircle circleWithPosition:circleCenter 
              radius:_slider.value]; 
    googleMapCircle.fillColor = [[UIColor purpleColor] colorWithAlphaComponent:.4f]; 
    googleMapCircle.strokeColor = [UIColor purpleColor]; 
    googleMapCircle.strokeWidth = 5; 
    googleMapCircle.tappable=YES; 
    googleMapCircle.map = _googleMap; 


}