iphone开发之绘制地图道路

iphone开发之绘制地图线路
地图应用经常会涉及到线路的绘制问题，ios下可以使用MKMapView进行地图开发，使用

MKOverlayView进行线路的绘制。

使用MKMapView添加MKMap.framework 和CoreLocation.framework并导入

MapKit.h头文件。

新建一个基于视图的工程，修改头文件：

//// CloViewController.h// LocationMapTest//// Created by Cloay on 12-6-18.// Copyright (c) 2012年 __MyCompanyName__. All rights reserved.//#import <UIKit/UIKit.h>#import <MapKit/MapKit.h>#import "CloMKAnnotation.h"@interface CloViewController : UIViewController<CLLocationManagerDelegate, MKMapViewDelegate, UIActionSheetDelegate>{ MKMapView *cloMapView; MKPolyline *routeLine;}@property (nonatomic, strong) NSMutableArray *locations;@end
修改实现代码，在.m中添加如下代码：

//// CloViewController.m// LocationMapTest//// Created by Cloay on 12-6-18.// Copyright (c) 2012年 __MyCompanyName__. All rights reserved.//#import "CloViewController.h"@interface CloViewController ()@end@implementation CloViewController@synthesize locations;- (void)viewDidLoad{ [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. cloMapView = [[MKMapView alloc] initWithFrame:[self.view bounds]]; [cloMapView setMapType:MKMapTypeHybrid]; //设置地图类型 地图/卫星/两者结合 [cloMapView setShowsUserLocation:YES]; //显示当前位置 [cloMapView setDelegate:self]; CLLocationManager *locationManager = [[CLLocationManager alloc] init]; //设置CLLocationManager实例委托和精度 [locationManager setDelegate:self]; [locationManager setDesiredAccuracy:kCLLocationAccuracyBest]; //设置距离筛选器，表示至少移动100米才通知委托更新 [locationManager setDistanceFilter:100.f]; //启动更新请求// [locationManager startUpdatingLocation]; locations = [[NSMutableArray alloc] init]; float latitude = 39.8127; //维度 float longitude = 116.2967; //经度 for (int i = 0; i < 10; i++) { [locations addObject:[NSString stringWithFormat:@"%f,%f", latitude + 0.01*i, longitude + 0.01*i]];// NSLog(@"locations:%i",locations.count); } //地图初始 CLLocationCoordinate2D coords; coords.latitude = 39.9127; coords.longitude = 116.3967; float zoomlevel = 0.22; MKCoordinateRegion region = MKCoordinateRegionMake(coords, MKCoordinateSpanMake(zoomlevel, zoomlevel)); [cloMapView setRegion:[cloMapView regionThatFits:region] animated:YES]; [cloMapView addOverlay:[self makePolylineWithLocations:locations]]; [self.view addSubview:cloMapView]; }- (void)viewDidUnload{ [super viewDidUnload]; // Release any retained subviews of the main view. cloMapView = nil;}- (void)dealloc{ [cloMapView release]; [super dealloc];}- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation{ return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);}//显示菜单选项- (void)showActionSheet :(id)sender{ UIActionSheet * actionSheet = [[UIActionSheet alloc] initWithTitle:nil delegate:self cancelButtonTitle:@"取消" destructiveButtonTitle:@"添加足迹" otherButtonTitles:@"分享",@"详细",@"删除", nil]; [actionSheet setDelegate:self]; [actionSheet showInView:self.view]; [actionSheet release];}//根据坐标点生成线路- (MKPolyline *)makePolylineWithLocations:(NSMutableArray *)newLocations{ MKMapPoint *pointArray = malloc(sizeof(CLLocationCoordinate2D)* newLocations.count); for(int i = 0; i < newLocations.count; i++) { // break the string down even further to latitude and longitude fields. NSString* currentPointString = [newLocations objectAtIndex:i]; NSArray* latLonArr = [currentPointString componentsSeparatedByCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@","]]; CLLocationDegrees latitude = [[latLonArr objectAtIndex:0] doubleValue]; // NSLog(@"latitude-> %f", latitude); CLLocationDegrees longitude = [[latLonArr objectAtIndex:1] doubleValue]; CLLocationCoordinate2D coordinate = CLLocationCoordinate2DMake(latitude, longitude); // NSLog(@"point-> %f", point.x); if (i == 0 || i == locations.count - 1) {//这里只添加起点和终点作为测试 CloMKAnnotation *ann = [[CloMKAnnotation alloc] init]; [ann setCoordinate:coordinate]; [ann setTitle:[NSString stringWithFormat:@"纬度:%f", latitude]]; [ann setSubtitle:[NSString stringWithFormat:@"经度:%f", longitude]]; [cloMapView addAnnotation:ann]; } pointArray[i] = MKMapPointForCoordinate(coordinate); } routeLine = [MKPolyline polylineWithPoints:pointArray count:newLocations.count]; free(pointArray); return routeLine;}#pragma mark-#pragma CLLocationManager delegate method//位置变化后会调用- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{ //可在此处更新用户位置信息// cloMapView.userLocation NSLog(@"oldLocation:%@", [oldLocation description]); NSLog(@"newLocation:%@", [newLocation description]); NSLog(@"distance:%@", [newLocation distanceFromLocation:oldLocation]); //位置变化添加新位置点 [locations addObject:[NSString stringWithFormat:@"%f,%f", newLocation.coordinate.latitude, newLocation.coordinate.longitude]]; //删除进线路，更新新轨迹 [cloMapView removeOverlay:routeLine]; [cloMapView addOverlay:[self makePolylineWithLocations:locations]];}#pragma MKMapView delegate method//添加坐标点大头针- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation{ if (![annotation isKindOfClass:[CloMKAnnotation class]]) { return nil; } static NSString *identifier = @"Annotation"; MKPinAnnotationView *pinAnnotationView = (MKPinAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:identifier]; if (pinAnnotationView == nil) { pinAnnotationView = [[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier] autorelease]; } pinAnnotationView.animatesDrop = YES; pinAnnotationView.canShowCallout = YES; pinAnnotationView.draggable = YES; UIButton *detailBtn = [UIButton buttonWithType:UIButtonTypeDetailDisclosure]; [detailBtn addTarget:self action:@selector(showActionSheet:) forControlEvents:UIControlEventTouchUpInside]; pinAnnotationView.rightCalloutAccessoryView = detailBtn; return pinAnnotationView;}- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)view didChangeDragState:(MKAnnotationViewDragState)newState fromOldState:(MKAnnotationViewDragState)oldState{ }//画线- (MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id<MKOverlay>)overlay{ NSLog(@"return overLayView..."); if ([overlay isKindOfClass:[MKPolyline class]]) { MKPolylineView *routeLineView = [[[MKPolylineView alloc] initWithPolyline:routeLine] autorelease]; routeLineView.strokeColor = [UIColor blueColor]; routeLineView.lineWidth = 3; return routeLineView; } return nil;}@end
这里主要是为了测试，初始时 locations坐标点自定义的，实际中是根据用户的位置动态生成的一系列坐标点。具体可在

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation函数中实现，如上代码。

另外用户的实时位置可用

cloMapView.userLocation = newLocation进行设置，然后显示在地图上。
效果图如下：