固定在Google Maps iOS SDK中心的标记 [英] fixed marker on center of google map ios sdk

问题描述

我想将标记固定在地图中心，而不管位置坐标如何.如果用户在地图上移动相机，我希望它一直显示在中心，而标记上没有任何闪烁，并且显示了该标记上的新位置，请问该怎么办?请帮忙.谢谢

I want to fix the marker in the center of the map irrespective of the location coordinates. If the user moves the camera on map I want it to keep showing up in the center without any flickering in marker and new location on that marker shows,If it is possible then How can I do that? Please help out. Thanks

我正在使用iOS google map sdk(objective-c)

i am using iOS google map sdk(objective-c)

推荐答案

GMSCameraPosition *lastCameraPosition;

- (void)mapView:(GMSMapView *)pMapView didChangeCameraPosition:(GMSCameraPosition *)position {

        /* move draggable pin */
        if (movingMarker) {

            // stick it on map and start dragging from there..
            if (lastCameraPosition == nil) lastCameraPosition = position;

            // Algebra :) substract coordinates with the difference of camera changes
            double lat = position.target.latitude - lastCameraPosition.target.latitude;
            double lng = position.target.longitude - lastCameraPosition.target.longitude;
            lastCameraPosition = position;
            CLLocationCoordinate2D newCoords = CLLocationCoordinate2DMake(movingMarker.googleMarker.position.latitude+lat,
                                                                          movingMarker.googleMarker.position.longitude+lng);
            [movingMarker.googleMarker setPosition:newCoords];
            return;
        }

    }

    - (void)mapView:(GMSMapView *)mapView idleAtCameraPosition:(GMSCameraPosition *)position {

        lastCameraPosition = nil; // reset pin moving, no ice skating pins ;)

    }

现在，上面的代码使标记保持原样，但是在拖动屏幕时它正在飞行.

now the code above makes the marker stay as it was but it's flying while you drag the screen.

如果要使其首先居中，则必须将标记坐标设置为map.center->坐标转换，然后要做一些动画:

if you want it centered first the you have to set the marker coordinates to map.center -> coordinates conversion and then you have some animation to do:

CGPoint point = map.center; GMSCameraUpdate *camera =[GMSCameraUpdate setTarget:[map.projection coordinateForPoint:point]]; 
[map animateWithCameraUpdate:camera]; 

然后等待map:mapDidIdle

then wait for map:mapDidIdle

这篇关于固定在Google Maps iOS SDK中心的标记的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！