如何設置區域與谷歌地圖SDK的iOS？

Question

如何設置區域與谷歌地圖SDK的iOS？ 我想設置縮放標記的位置和半徑。

Answer 1

我通過框架的頭文件進行搜索，只找到可用於下面的代碼，可能是一個開始的接口。這裏的問題是，我無法在其他頭文件中找到任何GMSCoordinateBounds的導入，所以我找不到在GMSMapView中顯示此區域的方法。

GMSVisibleRegion region; 
region.farLeft = CLLocationCoordinate2DMake(farLeftLatitude, farLeftlongitude); 
region.farRight = CLLocationCoordinate2DMake(farRightlatitude, farRightlongitude); 

GMSCoordinateBounds *bounds = [[GMSCoordinateBounds alloc] initWithRegion:region]; 

Answer 2

UPDATE：

下原來的答案是過時的的SDK 1.2版本 - 您現在可以使用GMSCameraUpdate類的fitBounds:方法：

https://developers.google.com/maps/documentation/ios/reference/interface_g_m_s_camera_update

---

原始回答：

MapKit中的MKMapPoint類型定義了地圖的2D投影。儘管投影的實際值是不透明的，但它們相當於縮放級別爲20的像素。這可用於將經度/緯度值轉換爲像素，從而將比例轉換爲縮放比例，從而縮放比例。

首先定義兩個位置，指定要顯示的區域的邊界。這可能是邊界框的對角，或只有兩個位置，例如：

CLLocationCoordinate2D location1 = 
    CLLocationCoordinate2DMake(-33.8683, 151.2086); // Sydney 
CLLocationCoordinate2D location2 = 
    CLLocationCoordinate2DMake(-31.9554, 115.8585); // Perth 

如果要包括兩個以上的點，你可以計算出他們自己的邊界。這也可以使用GMSCoordinateBounds完成，例如：

GMSCoordinateBounds* bounds = 
    [[GMSCoordinateBounds alloc] 
    initWithCoordinate: CLLocationCoordinate2DMake(-33.8683, 151.2086) // Sydney 
    andCoordinate: CLLocationCoordinate2DMake(-31.9554, 115.8585)]; // Perth 
bounds = [bounds including: 
    CLLocationCoordinate2DMake(-12.4667, 130.8333)]; // Darwin 
CLLocationCoordinate2D location1 = bounds.southWest; 
CLLocationCoordinate2D location2 = bounds.northEast; 

接下來，你需要獲得在點地圖視圖的大小。你可以使用這個：

float mapViewWidth = _mapView.frame.size.width; 
float mapViewHeight = _mapView.frame.size.height; 

但是，這隻會在你已經創建地圖視圖時才起作用。另外，如果您使用getting started guide中的示例代碼，則該幀將設置爲CGRectZero，因爲稍後將設置實際大小以填充屏幕。在這種情況下，如果你正在創建一個全屏幕的地圖，那麼你可能想是這樣的：

float mapViewWidth = [UIScreen mainScreen].applicationFrame.size.width; 
float mapViewHeight = [UIScreen mainScreen].applicationFrame.size.height; 

否則，使用它你創建你的地圖視圖大小。

現在你算算相機位置所需的信息：

MKMapPoint point1 = MKMapPointForCoordinate(location1); 
MKMapPoint point2 = MKMapPointForCoordinate(location2); 

MKMapPoint centrePoint = MKMapPointMake(
    (point1.x + point2.x)/2, 
    (point1.y + point2.y)/2); 
CLLocationCoordinate2D centreLocation = MKCoordinateForMapPoint(centrePoint); 

double mapScaleWidth = mapViewWidth/fabs(point2.x - point1.x); 
double mapScaleHeight = mapViewHeight/fabs(point2.y - point1.y); 
double mapScale = MIN(mapScaleWidth, mapScaleHeight); 

double zoomLevel = 20 + log2(mapScale); 

GMSCameraPosition *camera = [GMSCameraPosition 
    cameraWithLatitude: centreLocation.latitude 
    longitude: centreLocation.longitude 
    zoom: zoomLevel]; 

然後，您可以用這臺相機初始化地圖視圖，或設置地圖視圖這臺相機。

爲使該代碼編譯，你需要將MapKit框架添加到您的項目，然後同時導入：

#import <MapKit/MapKit.h> 

請注意，此代碼不處理環繞，如果你的座標跨越越過日期線。例如，如果您嘗試在東京和夏威夷使用此代碼，而不是顯示太平洋地區，它將嘗試顯示幾乎整個世界。在肖像模式下，不可能縮小到足以在左側看到夏威夷以及在右側看到東京，因此地圖最終以非洲爲中心，而兩個位置都不可見。如果你願意的話，你可以修改上面的代碼來處理日期行處理。

Answer 3

我目前正在使用這種方法。

self.markers是一個字典，其中標記存儲在一個位置ID中，self.currentLocation是一個CLLocation2D，self.mapView是一個GMSMapView。

這裏的數學是檢查是否匹配寬度或高度的大小，然後根據x1/pow（2，zoom1）= x2/pow（2，縮放2）」，從而放大2 = LOG 2（X2 * POW（2 self.mapView.camera.zoom）/ X1）。

- (void)fitMarkers 
{ 
    if (2 > self.markers.count) 
    { 
     [self.mapView animateToCameraPosition:[GMSCameraPosition cameraWithTarget:self.currentLocation.coordinate zoom:kZoom]]; 

     return; 
    } 

    NSArray* markers = self.markers.allValues; 

    GMSCoordinateBounds* markerBounds = [[GMSCoordinateBounds alloc] initWithCoordinate:((id<GMSMarker>)markers[0]).position andCoordinate:((id<GMSMarker>)markers[1]).position]; 

    for (id<GMSMarker> marker in markers) 
    { 
     markerBounds = [markerBounds including:marker.position]; 
    } 

    // get marker bounds in points 
    CGPoint markerBoundsTopLeft = [self.mapView.projection pointForCoordinate:CLLocationCoordinate2DMake(markerBounds.northEast.latitude, markerBounds.southWest.longitude)]; 
    CGPoint markerBoundsBottomRight = [self.mapView.projection pointForCoordinate:CLLocationCoordinate2DMake(markerBounds.southWest.latitude, markerBounds.northEast.longitude)]; 

    // get user location in points 
    CGPoint currentLocation = [self.mapView.projection pointForCoordinate:self.currentLocation.coordinate]; 

    CGPoint markerBoundsCurrentLocationMaxDelta = CGPointMake(MAX(fabs(currentLocation.x - markerBoundsTopLeft.x), fabs(currentLocation.x - markerBoundsBottomRight.x)), MAX(fabs(currentLocation.y - markerBoundsTopLeft.y), fabs(currentLocation.y - markerBoundsBottomRight.y))); 

    // the marker bounds centered on self.currentLocation 
    CGSize centeredMarkerBoundsSize = CGSizeMake(2.0 * markerBoundsCurrentLocationMaxDelta.x, 2.0 * markerBoundsCurrentLocationMaxDelta.y); 

    // inset the view bounds to fit markers 
    CGSize insetViewBoundsSize = CGSizeMake(self.mapView.bounds.size.width - kMarkerSize/2.0 - kMarkerMargin, self.mapView.bounds.size.height - kMarkerSize/2.0 - kMarkerSize); 

    CGFloat x1; 
    CGFloat x2; 

    // decide which axis to calculate the zoom level with by comparing the width/height ratios 
    if (centeredMarkerBoundsSize.width/centeredMarkerBoundsSize.height > insetViewBoundsSize.width/insetViewBoundsSize.height) 
    { 
     x1 = centeredMarkerBoundsSize.width; 
     x2 = insetViewBoundsSize.width; 
    } 
    else 
    { 
     x1 = centeredMarkerBoundsSize.height; 
     x2 = insetViewBoundsSize.height; 
    } 

    CGFloat zoom = log2(x2 * pow(2, self.mapView.camera.zoom)/x1); 

    GMSCameraPosition* camera = [GMSCameraPosition cameraWithTarget:self.currentLocation.coordinate zoom:zoom]; 

    [self.mapView animateToCameraPosition:camera]; 
} 

Answer 4

Saxun德魯斯的答案是真的很好。但除此之外，如果你想從任何位置計算半徑，你可以做到這一點與下面的代碼：

CLLocationCoordinate2D center = CLLocationCoordinate2DMake([currentLocationLat doubleValue],[currentLocationLong doubleValue]); 
float radius = 25*1000; //radius in meters (25km) 

MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance(center, radius*2, radius*2); 

CLLocationCoordinate2D northEast = CLLocationCoordinate2DMake(region.center.latitude - region.span.latitudeDelta/2, region.center.longitude - region.span.longitudeDelta/2); 
CLLocationCoordinate2D southWest = CLLocationCoordinate2DMake(region.center.latitude + region.span.latitudeDelta/2, region.center.longitude + region.span.longitudeDelta/2); 

GMSCoordinateBounds* bounds = [[GMSCoordinateBounds alloc] 
           initWithCoordinate: northEast 
           andCoordinate: southWest]; 

Answer 5

UPDATE

所有問題都已在最新版本的Google地圖（1.5）中修復。 [mapView_ animateWithCameraUpdate:[GMSCameraUpdate fitBounds:bounds]];可以noow來代替代碼的下方

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原來的答案

[GMSCameraUpdate fitBounds]標準方法不會在我的版本的SDK（1.2.0）中給出準確的結果。我正在使用下面的代碼而不是它。公式取自Mercator Projection。根據Google Documentation，世界經緯度限制在85度。

#import <stdlib.h> 

-(void) animateBoundsNorth:(CGFloat)north West:(CGFloat)west South:(CGFloat)south East:(CGFloat)east Padding:(int)padding { 

    CGFloat northRad = north * M_PI/180.0; 
    CGFloat northProj = logf(tanf(M_PI_4 + northRad/2.0)); 
    CGFloat southRad = south * M_PI/180.0; 
    CGFloat southProj = logf(tanf(M_PI_4 + southRad/2.0)); 
    CGFloat topRad = 85.0 * M_PI/180.0; 
    CGFloat topProj = logf(tanf(M_PI_4 + topRad/2.0)); 
    CGFloat zoomLat = log2f((mapView_.bounds.size.height - padding * 2) * 2 * topProj /(northProj - southProj)) - 8; 
    CGFloat zoomLon = log2f((mapView_.bounds.size.width - padding * 2) * 360/(east - west)) - 8; 

    GMSCameraUpdate *update = [GMSCameraUpdate setTarget:CLLocationCoordinate2DMake((north+south)/2.0, (west+east)/2.0) zoom:MIN(zoomLat, zoomLon)]; 


    [mapView_ animateWithCameraUpdate:update]; 


} 

Answer 6

正如2014年6月的，this answer是遍歷標記的給定陣列，然後相應地設置邊界的最簡單方式。

Answer 7

按照GoogleMaps的新版本iOS sdk 1.9.2, 我們可以使用Camera的位置，縮放級別，viewingAngle進行設置。

GMSCameraPosition* camera = [GMSCameraPosition cameraWithLatitude:28.6100 
                  longitude:77.2300 
                   zoom:14.0 
                   bearing:0 
                 viewingAngle:0.00]; 
    self.mapView = [GMSMapView mapWithFrame:CGRectMake(0, 45, self.view.frame.size.width, self.view.frame.size.height - 45) camera:camera]; 
    mapView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; 

    mapView.delegate = self; 
    mapView.myLocationEnabled = YES; 
    mapView.mapType = kGMSTypeTerrain; 
    mapView.settings.compassButton = YES; 
    mapView.settings.myLocationButton = YES; 
    [self.mapView setMinZoom:10 maxZoom:18]; 

    GMSMarker* marker = [[GMSMarker alloc] init]; 
    marker.position = CLLocationCoordinate2DMake(28.6100, 77.2300); 
    marker.title = @"New Delhi"; 
    marker.snippet = @"Capital Of India"; 

    marker.map = self.mapView; 
    marker.appearAnimation = kGMSMarkerAnimationPop; 
    marker.icon = [GMSMarker markerImageWithColor:[UIColor grayColor]]; 
    [self.view addSubview:self.mapView]; 

有關進一步的參考see this PDF document。

你還可以設置最小和最大縮放級別根據自己的需要：

[self.mapView setMinZoom:10 maxZoom:30]; 

希望這解決了這個問題。

Answer 8

如果你有「極左」和谷歌地圖的「接近權」的角落，你可以使用下面的代碼

 var region:GMSVisibleRegion = GMSVisibleRegion() 
    region.nearLeft = CLLocationCoordinate2DMake(nearleflat, nearleftlong) 
    region.farRight = CLLocationCoordinate2DMake(fareastlat,fareastlong) 
    let bounds = GMSCoordinateBounds(coordinate: region.nearLeft,coordinate: region.farRight) 
    let camera = googleMapView.cameraForBounds(bounds, insets:UIEdgeInsetsZero) 
    googleMapView.camera = camera; 

This鏈接也可能會顯示在SWIFT數據的緯度和經度有助於相關的事情。

Answer 9

//我發現這個方法對我來說

func setMapZoomToRadius(lat:Double, lng:Double, var mile:Double) 
    { 

     let center = CLLocationCoordinate2DMake(lat, lng)   
     let radius: Double = (mile) * 621.371 

     let region = MKCoordinateRegionMakeWithDistance(center, radius * 2.0, radius * 2.0) 


     let northEast = CLLocationCoordinate2DMake(region.center.latitude - region.span.latitudeDelta, region.center.longitude - region.span.longitudeDelta) 
     let southWest = CLLocationCoordinate2DMake(region.center.latitude + region.span.latitudeDelta, region.center.longitude + region.span.longitudeDelta) 


     print("\(region.center.longitude) \(region.span.longitudeDelta)") 
     let bounds = GMSCoordinateBounds(coordinate: southWest, coordinate: northEast) 

     let camera = googleMapView.cameraForBounds(bounds, insets:UIEdgeInsetsZero) 
     googleMapView.camera = camera; 

     }