Question

我有一张正确显示的地图，我现在唯一要做的就是在加载时设置缩放级别。有没有办法做到这一点？

由于

Answer 1

我发现自己是一个解决方案，这很简单并且可以解决问题。使用MKCoordinateRegionMakeWithDistance可以垂直和水平设置以米为单位的距离，以获得所需的缩放。当然，当您更新您的位置时，您将获得正确的坐标，或者您可以在启动时直接在CLLocationCoordinate2D中指定它，如果您需要这样做：

CLLocationCoordinate2D noLocation;
MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(noLocation, 500, 500);
MKCoordinateRegion adjustedRegion = [self.mapView regionThatFits:viewRegion];          
[self.mapView setRegion:adjustedRegion animated:YES];
self.mapView.showsUserLocation = YES;

夫特：

let location = ...
let region = MKCoordinateRegionMakeWithDistance(location.coordinate, CLLocationDistance(exactly: 5000)!, CLLocationDistance(exactly: 5000)!)
mapView.setRegion(mapView.regionThatFits(region), animated: true)

Answer 2

基于经度线在地图的任何位置均匀间隔的事实，有一个非常简单的实现来设置centerCoordinate和zoomLevel：

@interface MKMapView (ZoomLevel)

@property (assign, nonatomic) NSUInteger zoomLevel;

- (void)setCenterCoordinate:(CLLocationCoordinate2D)centerCoordinate
                  zoomLevel:(NSUInteger)zoomLevel
                   animated:(BOOL)animated;

@end


@implementation MKMapView (ZoomLevel)

- (void)setZoomLevel:(NSUInteger)zoomLevel {
    [self setCenterCoordinate:self.centerCoordinate zoomLevel:zoomLevel animated:NO];
}

- (NSUInteger)zoomLevel {
    return log2(360 * ((self.frame.size.width/256) / self.region.span.longitudeDelta)) + 1;
}

- (void)setCenterCoordinate:(CLLocationCoordinate2D)centerCoordinate
zoomLevel:(NSUInteger)zoomLevel animated:(BOOL)animated {
    MKCoordinateSpan span = MKCoordinateSpanMake(0, 360/pow(2, zoomLevel)*self.frame.size.width/256);
    [self setRegion:MKCoordinateRegionMake(centerCoordinate, span) animated:animated];
}

@end

Answer 3

它没有内置，但我看过/使用过this代码。这允许你使用它：

[mapView setCenterCoordinate:myCoord zoomLevel:13 animated:YES];

注意：这不是我的代码，我没有写，所以因此不能归功于它

Answer 4

您还可以使用MKCoordinateRegion进行缩放并设置其范围纬度＆amp;经度三角洲。以下是快速参考，here是iOS参考。它不会做任何花哨的事情，但应该允许你在绘制地图时设置缩放。

MKCoordinateRegion region;
region.center.latitude = {desired lat};
region.center.longitude = {desired lng};
region.span.latitudeDelta = 1;
region.span.longitudeDelta = 1;
mapView.region = region;

修改1：

MKCoordinateRegion region;
region.center.latitude = {desired lat};
region.center.longitude = {desired lng};
region.span.latitudeDelta = 1;
region.span.longitudeDelta = 1;
region = [mapView regionThatFits:region];
[mapView setRegion:region animated:TRUE];

Answer 5

一个简单的Swift实现，如果你使用outlet。

@IBOutlet weak var mapView: MKMapView! {
    didSet {
        let noLocation = CLLocationCoordinate2D()
        let viewRegion = MKCoordinateRegionMakeWithDistance(noLocation, 500, 500)
        self.mapView.setRegion(viewRegion, animated: false)
    }
}

根据@ Carnal的回答。

Answer 6

对于 Swift 3 ，这是非常快的：

private func setMapRegion(for location: CLLocationCoordinate2D, animated: Bool)
{
    let viewRegion = MKCoordinateRegionMakeWithDistance(location, <#T##latitudinalMeters: CLLocationDistance##CLLocationDistance#>, <#T##longitudinalMeters: CLLocationDistance##CLLocationDistance#>)
    MapView.setRegion(viewRegion, animated: animated)
}

只需定义lat-，long-Meters <CLLocationDistance>，mapView就会使缩放级别适合您的值。

Answer 7

基于@AdilSoomro的伟大answer。我想出了这个：

@interface MKMapView (ZoomLevel)
- (void)setCenterCoordinate:(CLLocationCoordinate2D)centerCoordinate
                  zoomLevel:(NSUInteger)zoomLevel
                   animated:(BOOL)animated;

-(double) getZoomLevel;
@end



@implementation MKMapView (ZoomLevel)

- (void)setCenterCoordinate:(CLLocationCoordinate2D)centerCoordinate
                  zoomLevel:(NSUInteger)zoomLevel animated:(BOOL)animated {
    MKCoordinateSpan span = MKCoordinateSpanMake(0, 360/pow(2, zoomLevel)*self.frame.size.width/256);
    [self setRegion:MKCoordinateRegionMake(centerCoordinate, span) animated:animated];
}


-(double) getZoomLevel {
    return log2(360 * ((self.frame.size.width/256) / self.region.span.longitudeDelta));
}

@end

Answer 8

我希望以下代码片段对您有帮助。

- (void)handleZoomOutAction:(id)sender {
    MKCoordinateRegion newRegion=MKCoordinateRegionMake(mapView.region.center,MKCoordinateSpanMake(mapView.region.s       pan.latitudeDelta/0.5, mapView.region.span.longitudeDelta/0.5));
    [mapView setRegion:newRegion];
}


- (void)handleZoomInAction:(id)sender {
    MKCoordinateRegion newRegion=MKCoordinateRegionMake(mapView.region.center,MKCoordinateSpanMake(mapView.region.span.latitudeDelta*0.5, mapView.region.span.longitudeDelta*0.5));
    [mapView setRegion:newRegion];
}

您可以选择任意值而不是0.5来减小或增加缩放级别。我点击了两个按钮就使用了这些方法。

Answer 9

我知道这是一个迟到的回复，但我只是想解决自己设置缩放级别的问题。 goldmine的答案很棒，但我发现它在我的应用程序中运行得不够好。

经过仔细检查，金矿表示“经度线在地图的任何一点均匀分布”。事实并非如此，实际上纬度线从-90（南极）到+90（北极）的距离相等。经度线在赤道处最宽处汇合，汇聚到极点处。

因此我采用的实施方法是使用纬度计算如下：

@implementation MKMapView (ZoomLevel)

- (void)setCenterCoordinate:(CLLocationCoordinate2D)coordinate
    zoomLevel:(NSUInteger)zoom animated:(BOOL)animated
{
    MKCoordinateSpan span = MKCoordinateSpanMake(180 / pow(2, zoom) * 
        self.frame.size.height / 256, 0);
    [self setRegion:MKCoordinateRegionMake(coordinate, span) animated:animated];
}

@end

希望在这个晚期阶段有所帮助。

Answer 10

使用NSUserDefaults的Swift 2.0答案可以保存和恢复地图的缩放和位置。

保存地图位置和缩放的功能：

func saveMapRegion() {
    let mapRegion = [
        "latitude" : mapView.region.center.latitude,
        "longitude" : mapView.region.center.longitude,
        "latitudeDelta" : mapView.region.span.latitudeDelta,
        "longitudeDelta" : mapView.region.span.longitudeDelta
    ]
    NSUserDefaults.standardUserDefaults().setObject(mapRegion, forKey: "mapRegion")
}

每次移动地图时运行该功能：

func mapView(mapView: MKMapView, regionDidChangeAnimated animated: Bool) 
{
        saveMapRegion();
}

保存地图缩放和位置的功能：

func restoreMapRegion() 
{
    if let mapRegion = NSUserDefaults.standardUserDefaults().objectForKey("mapRegion") 
    {

        let longitude = mapRegion["longitude"] as! CLLocationDegrees
        let latitude = mapRegion["latitude"] as! CLLocationDegrees
        let center = CLLocationCoordinate2D(latitude: latitude, longitude: longitude)

        let longitudeDelta = mapRegion["latitudeDelta"] as! CLLocationDegrees
        let latitudeDelta = mapRegion["longitudeDelta"] as! CLLocationDegrees
        let span = MKCoordinateSpan(latitudeDelta: latitudeDelta, longitudeDelta: longitudeDelta)

        let savedRegion = MKCoordinateRegion(center: center, span: span)

        self.mapView.setRegion(savedRegion, animated: false)
    }
}

将此添加到viewDidLoad：

restoreMapRegion()

Answer 11

迅速：

?scatterplot

locValue是您的坐标。

Answer 12

基于quentinadam的answer

Swift 5.1

// size refers to the width/height of your tile images, by default is 256.0
// Seems to get better results using round()
// frame.width is the width of the MKMapView

let zoom = round(log2(360 * Double(frame.width) / size / region.span.longitudeDelta))

Answer 13

基于this answer的

MKMapView扩展名（+浮点缩放级别精度）：

import Foundation
import MapKit

extension MKMapView {
    var zoomLevel: Double {
        get {
            return log2(360 * (Double(self.frame.size.width / 256) / self.region.span.longitudeDelta)) + 1
        }

        set (newZoomLevel){
            setCenterCoordinate(coordinate:self.centerCoordinate, zoomLevel: newZoomLevel, animated: false)
        }
    }

    private func setCenterCoordinate(coordinate: CLLocationCoordinate2D, zoomLevel: Double, animated: Bool) {
        let span = MKCoordinateSpan(latitudeDelta: 0, longitudeDelta: 360 / pow(2, zoomLevel) * Double(self.frame.size.width) / 256)
        setRegion(MKCoordinateRegion(center: coordinate, span: span), animated: animated)
    }
}

Answer 14

在这里，我将我的答案及其用于 swift 4.2 的工作。

MKMapView center and zoom in

设置MKMapView的缩放级别

14 个答案: