iOS原生地圖開發進階——使用導航和附近興趣點檢索（二）

2、進行線路導航

- (void)viewDidLoad {
    [super viewDidLoad];
    //地圖初始化設定
    mapView =[[MKMapView alloc]initWithFrame:self.view.frame];
    mapView.region=MKCoordinateRegionMake(CLLocationCoordinate2DMake(39.26, 116.3), MKCoordinateSpanMake(5, 5));
    mapView.mapType=MKMapTypeStandard;
    mapView.delegate=self;
    [self.view addSubview:mapView];
    
    //導航設定
    CLLocationCoordinate2D fromcoor=CLLocationCoordinate2DMake(39.26, 116.3);
    CLLocationCoordinate2D tocoor = CLLocationCoordinate2DMake(33.33, 113.33);
    //建立出發點和目的點資訊
    MKPlacemark *fromPlace = [[MKPlacemark alloc] initWithCoordinate:fromcoor
                                                       addressDictionary:nil];
    MKPlacemark *toPlace = [[MKPlacemark alloc]initWithCoordinate:tocoor addressDictionary:nil];
    //建立出發節點和目的地節點
    MKMapItem * fromItem = [[MKMapItem alloc]initWithPlacemark:fromPlace];
    MKMapItem * toItem = [[MKMapItem alloc]initWithPlacemark:toPlace];
    //初始化導航搜尋請求
    MKDirectionsRequest *request = [[MKDirectionsRequest alloc]init];
    request.source=fromItem;
    request.destination=toItem;
    request.requestsAlternateRoutes=YES;
    //初始化請求檢索
    MKDirections *directions = [[MKDirections alloc]initWithRequest:request];
    //開始檢索，結果會傳回在block中
    [directions calculateDirectionsWithCompletionHandler:^(MKDirectionsResponse *response, NSError *error) {
        if (error) {
            NSLog(@"error:%@",error);
        }else{
            //提取導航線路結果中的一條線路
            MKRoute *route =response.routes[0];
            //将線路中的每一步詳情提取出來
            NSArray * stepArray = [NSArray arrayWithArray:route.steps];
            //進行周遊
            for (int i=0; i<stepArray.count; i++) {
                //線路的詳情節點
                MKRouteStep * step = stepArray[i];
                //在此節點處添加一個大頭針
                MKPointAnnotation * point = [[MKPointAnnotation alloc]init];
                point.coordinate=step.polyline.coordinate;
                point.title=step.instructions;
                point.subtitle=step.notice;
                [mapView addAnnotation:point];
                //将此段線路添加到地圖上
                [mapView addOverlay:step.polyline];
            }
        }
    }];  
}
//地圖覆寫物的代理方法
-(MKOverlayRenderer *)mapView:(MKMapView *)mapView rendererForOverlay:(id<MKOverlay>)overlay{
    MKPolylineRenderer *renderer = [[MKPolylineRenderer alloc] initWithPolyline:overlay];
    
    renderer.strokeColor = [UIColor redColor];
    
    renderer.lineWidth = 4.0;
    
    return  renderer;
}
//标注的代理方法
-(MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation{
    MKPinAnnotationView * view= [[MKPinAnnotationView alloc]initWithAnnotation:annotation reuseIdentifier:@"anno"];
    view.canShowCallout=YES;
    return view;
}      

效果如下：

二、附近興趣點檢索

興趣點檢索的邏輯和導航線路檢索的邏輯相似，直接通過代碼來示範：

//建立一個位置資訊對象，第一個參數為經緯度，第二個為緯度檢索範圍，機關為米，第三個為經度檢索範圍，機關為米
    MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance(tocoor, 5000, 5000);
    //初始化一個檢索請求對象
    MKLocalSearchRequest * req = [[MKLocalSearchRequest alloc]init];
    //設定檢索參數
    req.region=region;
    //興趣點關鍵字
    req.naturalLanguageQuery=@"hotal";
    //初始化檢索
    MKLocalSearch * ser = [[MKLocalSearch alloc]initWithRequest:req];
    //開始檢索，結果傳回在block中
    [ser startWithCompletionHandler:^(MKLocalSearchResponse *response, NSError *error) {
        //興趣點節點數組
        NSArray * array = [NSArray arrayWithArray:response.mapItems];
        for (int i=0; i<array.count; i++) {
            MKMapItem * item=array[i];
            MKPointAnnotation * point = [[MKPointAnnotation alloc]init];
            point.title=item.name;
            point.subtitle=item.phoneNumber;
            point.coordinate=item.placemark.coordinate;
            [mapView addAnnotation:point];
        }
    }];