当iphone到达某个位置时如何触发警报？

Posted 2023-03-05

【中文标题】当iphone到达某个位置时如何触发警报？

【英文标题】：How to trigger alert when iphone reaches a certain location?

【发布时间】：2012-07-22 00:34:43

【问题描述】：

我目前有一张显示用户当前位置的地图，还有几个注释标记（我还没有将它们放入一个数组中，但很快就会）。我试图让我的 iphone 应用程序在用户到达某些位置时触发警报。我怎么做？这就是我现在所拥有的......

ViewController.h

#import <UIKit/UIKit.h>
#import <CoreLocation/CoreLocation.h>
#import <MapKit/MapKit.h>
#import "MapAnnotation.h"

@interface ViewController : UIViewController <CLLocationManagerDelegate, MKMapViewDelegate>

    CLLocationManager *locationManager;
    IBOutlet MKMapView *worldView;



@end

查看控制器.m

#import "ViewController.h"


@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad

    [super viewDidLoad];
    [worldView setShowsUserLocation:YES];    




- (void)mapView:(MKMapView *)mapView
didUpdateUserLocation:(MKUserLocation *)userLocation


    CLLocationCoordinate2D loc = [userLocation coordinate];
    MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance(loc, 250, 250);
    [worldView setRegion:region animated:YES];  

    MKCoordinateRegion pin =  0.0, 0.0 , 0.0, 0.0  ;
    pin.center.latitude = 53.363581;
    pin.center.longitude = -6.258183;
    pin.span.longitudeDelta = 0.01f;
    pin.span.latitudeDelta = 0.01f;
    [worldView setRegion:pin animated:YES];

    MapAnnotation *stage1 = [[MapAnnotation alloc] init];
    stage1.title = @"Quinn's";
    stage1.coordinate = pin.center;
    [worldView addAnnotation:stage1];

    MKCoordinateRegion pin2 =  0.0, 0.0 , 0.0, 0.0  ;
    pin2.center.latitude = 53.364678;
    pin2.center.longitude = -6.263009;
    pin2.span.longitudeDelta = 0.01f;
    pin2.span.latitudeDelta = 0.01f;
    [worldView setRegion:pin2 animated:YES];

    MapAnnotation *stage2 = [[MapAnnotation alloc] init];
    stage2.title = @"Neighbour";
    stage2.coordinate = pin2.center;
    [worldView addAnnotation:stage2];


- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil

    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];

    if (self) 
        // Create location manager object
        locationManager = [[CLLocationManager alloc] init];

        // Setting Delegate as AnotherMapFirstViewController
        [locationManager setDelegate:self];

        // And we want it to be as accurate as possible
        // regardless of how much time/power it takes
        [locationManager setDesiredAccuracy:kCLLocationAccuracyBest];

            self.title = NSLocalizedString(@"First", @"First");
            self.tabBarItem.image = [UIImage imageNamed:@"first"];


    

    return self;


- (void)locationManager:(CLLocationManager *)manager
    didUpdateToLocation:(CLLocation *)newLocation
           fromLocation:(CLLocation *)oldLocation

    NSLog(@"%@", newLocation);


- (void)locationManager:(CLLocationManager *)manager
       didFailWithError:(NSError *)error

    NSLog(@"Could not find location: %@", error);



- (void)dealloc

    // Tell the location manager to stop sending us messages
    [locationManager setDelegate:nil];



@end

【问题讨论】：

我假设您还没有阅读此内容？ --> developer.apple.com/library/ios/#documentation/CoreLocation/… 滚动到“使用区域监控边界交叉点”部分

似乎您需要设置一个带有标记作为边界的地理围栏。请参阅以下堆栈溢出链接***.com/questions/8077691/…

【参考方案1】：

您想寻找区域监控。查看-[CLLocationManager startMonitoringForRegion:] 的文档。