蓝懿教育九月二十四日记录
添加自定义大头针
1）创建一个继承于NSOject的大头针对象类
2）在MKAnnotation类中导入MapKit，添加协议<MKAnnotation>
#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>
@interface MyAnnotation : NSObject<MKAnnotation>
3)按住command的键到<MKAnnotation>中查找要添加的属性，并删除只读readonly
添加大头针属性
@property (nonatomic) CLLocationCoordinate2D coordinate;
@property (nonatomic, copy) NSString *title;
@property (nonatomic, copy) NSString *subtitle;
可以创建对象属性，给大头针添加信息
@property (nonatomic, strong)Business *business;
4）在地图类中引入大头针类，创建大头针对象并给其属性赋值
添加在地图中
#import "MyAnnotation.h"
//从网络中提取信息
NSMutableDictionary *dic = [NSMutableDictionary dictionary];
NSUserDefaults *ud = [NSUserDefaults standardUserDefaults];
[dic setObject:[ud objectForKey:@"city"] forKey:@"city"];
NSArray *bussinesses = [DianpingApi requestBusinessesWithParams:dic];
//创建大头针，并将数组中的信息分别赋给大头针
for (Business *b in bussinesses) {
//排除掉不符合条件的信息（这里是位置信息不符合）
if (b.coord.latitude>200) {
continue;
}
//为每个信息创建相应的大头针，并将信息存储在大头针内
MyAnnotation *ann = [[MyAnnotation alloc]init];
ann.coordinate = b.coord;
ann.business = b;
//添加大头针到地图中
[self.mapView addAnnotation:ann];
//设置mapView的显示位置与缩放比例
[self.mapView setRegion:MKCoordinateRegionMake(b.coord, MKCoordinateSpanMake(.1, .1))];
}
5）在MapViewController类中引入#import "MyAnnotationView.h"，并添加<MKMapViewDelegate>协议并在storyboard中给mapView连线，添加协议
#import "MyAnnotationView.h"
@interface ViewController ()<MKMapViewDelegate>
6）按住Command键点击<MKMapViewDelegate>协议，寻找方法
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation;
显示在MapView中显示大头针（注释）
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation{
//如果Map页面中有大头针视图就复用原视图
MyAnnotationView *av = (MyAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:@"ann"];
if (!av) {
//如果MapView中没有大头针就通过自定义MKAnnotationView创建大头针图像
av = [[MyAnnotationView alloc]initWithAnnotation:annotation reuseIdentifier:@"ann"];
}
return av;
}
//给打头针添加点击事件
-(void)mapView:(MKMapView *)mapView didSelectAnnotationView:(MKAnnotationView *)view{
MyAnnotation *ann = view.annotation;
Business *b = ann.business;
UIViewController *vc = [[UIViewController alloc]init];
UIWebView *wv = [[UIWebView alloc]initWithFrame:vc.view.bounds];
NSURL *url = [NSURL URLWithString:b.path];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
[wv loadRequest:request];
[vc.view addSubview:wv];
[self.navigationController pushViewController:vc animated:YES];
}
7）在自定义MKAnnotationView中自定义Annotation的图像
打initWithFrame
将其修改为
- (instancetype)initWithAnnotation:(id<MKAnnotation>)annotation reuseIdentifier:(NSString *)reuseIdentifier
{
self = [super initWithAnnotation:annotation reuseIdentifier:reuseIdentifier];
if (self) {
<#statements#>
}
return self;
}
在其中修改大头针的图片、添加其他信息
- (instancetype)initWithAnnotation:(id<MKAnnotation>)annotation reuseIdentifier:(NSString *)reuseIdentifier
{
self = [super initWithAnnotation:annotation reuseIdentifier:reuseIdentifier];
if (self) {
//修改大头针的样式
// self.image = [UIImage imageNamed:@"index_map.png"];
//通过大头针提取信息，并将信息显示出来，
MyAnnotation *ann = annotation;
Business *b = ann.business;
NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:b.img]];
self.image = [UIImage imageWithData:data];
//设置大头针View的尺寸
self.bounds = CGRectMake(0, 0, 50, 50);
}
return self;
}