在MKMapView的當前位置周圍添加隨機MKAnnations

我有一個MKMapView，顯示當前用戶的位置。當我點擊導航欄中的按鈕時，我想隨機放置10個引腳。這些可以隨機放置在任何地方，但只能在當前可見地圖區域內和當前位置周圍放置。在MKMapView的當前位置周圍添加隨機MKAnnations

如何去做這樣的事情？有沒有辦法在用戶位置附近有一個長/緯度範圍，但在地圖區域內？那麼，我可以從這個範圍內隨機選擇？

基本上，我需要找到目前的MKCoordinateRegion有什麼座標可用。

有沒有更好的方法來解決這個問題？

來源

2012-05-22 Nic Hubbard

我想通了，這裏是我是如何做的：

/** 
* Adds new pins to the map 
* 
* @version $Revision: 0.1 
*/ 
+ (void)addPinsToMap:(MKMapView *)mapView amount:(int)howMany { 

    //First we need to calculate the corners of the map so we get the points 
    CGPoint nePoint = CGPointMake(mapView.bounds.origin.x + mapView.bounds.size.width, mapView.bounds.origin.y); 
    CGPoint swPoint = CGPointMake((mapView.bounds.origin.x), (mapView.bounds.origin.y + mapView.bounds.size.height)); 

    //Then transform those point into lat,lng values 
    CLLocationCoordinate2D neCoord = [mapView convertPoint:nePoint toCoordinateFromView:mapView]; 
    CLLocationCoordinate2D swCoord = [mapView convertPoint:swPoint toCoordinateFromView:mapView]; 

    // Loop 
    for (int y = 0; y < howMany; y++) { 
     double latRange = [MapUtility randomFloatBetween:neCoord.latitude andBig:swCoord.latitude]; 
     double longRange = [MapUtility randomFloatBetween:neCoord.longitude andBig:swCoord.longitude]; 

     // Add new waypoint to map 
     CLLocationCoordinate2D location = CLLocationCoordinate2DMake(latRange, longRange); 
     MPin *pin = [[MPin alloc] init]; 
     pin.coordinate = location; 
     [mapView addAnnotation:pin]; 

    }//end 

}//end 


/** 
* Random numbers 
* 
* @version $Revision: 0.1 
*/ 
+ (double)randomFloatBetween:(double)smallNumber andBig:(double)bigNumber { 
    double diff = bigNumber - smallNumber; 
    return (((double) (arc4random() % ((unsigned)RAND_MAX + 1))/RAND_MAX) * diff) + smallNumber; 
}//end

來源

2012-05-22 04:34:36

可以使用

看看下面的代碼，用戶位置和其他位置之間的距離，讓您的註解

#define DISTANCE_RADIUS  10.0 // in KM 
-(NSArray *)findNearMe:(NSArray *)lounges { 
NSMutableArray *arNearme = [NSMutableArray array]; 

CLLocation *currentLocation; 
for(NSDictionary *d in lounges) 
{ 

currentLocation = [[CLLocation alloc] initWithLatitude:29.33891 longitude:48.077202]; 

    CGFloat latitude=[[d valueForKey:@"latitude"] floatValue]; 
    CGFloat longitude=[[d valueForKey:@"longitude"] floatValue]; 
    CLLocation *newPinLocation=[[CLLocation alloc] initWithLatitude:latitude longitude:longitude]; 
    double distanceValue=[currentLocation distanceFromLocation:newPinLocation]; 

    if(distanceValue/1000.0<=DISTANCE_RADIUS) { 
     [arNearme addObject:d]; 
    } 
} 
return arNearme; 
}

它會返回用戶位置附近1到1000公里範圍內的數組。使用註釋數組並顯示註釋以與用戶位置一起映射視圖。

來源

2012-05-22 04:42:39 Hiren

在夫特3.0

func addPins() { 
    let nePoint = CGPoint(x: mapView.bounds.origin.x + mapView.bounds.size.width, y: mapView.bounds.origin.y) 
    let sePoint = CGPoint(x: mapView.bounds.origin.x, y: mapView.bounds.origin.y + mapView.bounds.size.height) 

    let neCoord = mapView.convert(nePoint, toCoordinateFrom: mapView) 
    let seCoord = mapView.convert(sePoint, toCoordinateFrom: mapView) 

    var y = 5 
    while y > 0 { 
     let latRange = randomBetweenNumbers(firstNum: Float(neCoord.latitude), secondNum: Float(seCoord.latitude)) 
     let longRange = randomBetweenNumbers(firstNum: Float(neCoord.longitude), secondNum: Float(seCoord.longitude)) 
     let location = CLLocationCoordinate2D(latitude: CLLocationDegrees(latRange), longitude: CLLocationDegrees(longRange)) 
     let pin = MKPointAnnotation() 
     pin.coordinate = location 
     pin.title = "Home" 
     mapView.addAnnotation(pin) 
     y -= 1 
    } 

} 

func randomBetweenNumbers(firstNum: Float, secondNum: Float) -> Float{ 
    return Float(arc4random())/Float(UINT32_MAX) * abs(firstNum - secondNum) + min(firstNum, secondNum) 
}

來源

2016-12-01 15:40:28 Niklas

在MKMapView的當前位置周圍添加隨機MKAnnations

回答

相關問題