每当我设置 MKMapKit 的 region 属性时,它都会使跨度加倍。
例如:
MKCoordinateRegion currentRegion = map.region; // assume the current center of region is around New-York and the span is 2 by 2
map.region = map.region; // assign the region to itself
MKCoordinateRegion newRegion = map.region;
// the span of newRegion is different (almost twice than currentRegion)
这里发生了什么?