iOS 使用百度地图，仿滴滴打车的定位方法。拖动时时定位

这里的思路：
（1）把图片放到屏幕的中间，这样在拖动的时候就不会跟随着地图移动了。
（2）百度地图提供了，View坐标和地理坐标转换的方法。正式这个方法的存在，方便我们及时的获取拖动后的，屏幕中间的图片所在位置的经纬度。



当拖动地图的时候，定位的图片一直在屏幕的中央，当拖动停止的时候会显示出具体的信息

#import "HouseTypeMapVC.h"

@interface HouseTypeMapVC ()<BMKMapViewDelegate,BMKLocationServiceDelegate,BMKGeoCodeSearchDelegate>{

BMKLocationService * _locService;

}
@property (nonatomic,strong) UIView * locationView;
@property (nonatomic,strong) UIImageView * locImageView;
@property (nonatomic,strong) UIView * messageView;
@property (nonatomic,strong) UILabel * addressLabel;
@property (nonatomic,strong) UIButton * sureButton;
@property (nonatomic,strong) NSString * name;
@property (nonatomic,assign) CLLocationCoordinate2D location2D;

@property (nonatomic, strong)BMKGeoCodeSearch* searchAddress;
@property (strong, nonatomic) IBOutlet BMKMapView *mapView;
@property (nonatomic,strong)BMKUserLocation *userLocation; //定位功能
@end

@implementation HouseTypeMapVC

-(void)viewWillAppear:(BOOL)animated{

[super viewWillAppear: animated];
[_mapView viewWillAppear];
_mapView.delegate = self; // 此处记得不用的时候需要置nil，否则影响内存的释放
_locService.delegate = self;
}

-(void)viewWillDisappear:(BOOL)animated{
[_mapView viewWillDisappear];
_mapView.delegate = nil; // 不用时，置nil
_locService.delegate = nil;
}

- (void)viewDidLoad {
[super viewDidLoad];
}

- (void)initUI{
[self goBackBtn];
_mapView.mapType=BMKMapTypeStandard;
[self initlocationService];

}

#pragma mark --initlocationService--定位

-(void)initlocationService{

_locService = [[BMKLocationService alloc]init];

[_locService startUserLocationService];
_mapView.showsUserLocation = NO;//先关闭显示的定位图层
_mapView.userTrackingMode = BMKUserTrackingModeNone;//设置定位的状态
_mapView.showsUserLocation = YES;//显示定位图层
_mapView.showMapScaleBar = YES;//显示比例尺
_mapView.zoomLevel = 17;//地图显示的级别

_searchAddress = [[BMKGeoCodeSearch alloc]init];
_searchAddress.delegate = self;

}

//这里是创建中心显示的图片和显示详细地址的View

- (void)createLocationSignImage{

//LocationView定位在当前位置，换算为屏幕的坐标，创建的定位的图标

self.locationView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 28, 35)];
self.locImageView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 28, 35)];
self.locImageView.image = [UIImage imageNamed:@"myLocation"];
[self.locationView addSubview:self.locImageView];

//messageView 展示定位信息的View和Label和button

self.messageView = [[UIView alloc]init];
self.messageView.backgroundColor = [UIColor whiteColor];

//把当前定位的经纬度换算为了View上的坐标

CGPoint point = [self.mapView convertCoordinate:_mapView.centerCoordinate toPointToView:_mapView];

//当解析出现错误的时候，会出现超出屏幕的情况，一种是大于了屏幕，一种是小于了屏幕
if(point.x > ScreenWidth || point.x < ScreenWidth/5){

point.x = _mapView.centerX;
point.y = _mapView.centerY-64;

}

NSLog(@"Point------%f-----%f",point.x,point.y);
//重新定位了LocationView

self.locationView.center = point;

[self.locationView setFrame:CGRectMake(point.x-14, point.y-18, 28, 35)];

//重新定位了messageView
[self.messageView setFrame:CGRectMake(30, point.y-40-20, SCREEN_WIDTH-60, 40)];

//展示地址信息的label
self.addressLabel = [[UILabel alloc]initWithFrame:CGRectMake(10, 0, self.messageView.frame.size.width - 80, 40)];

self.addressLabel.font = [UIFont systemFontOfSize:13.0f];

[self.messageView addSubview:self.addressLabel];

//把地址信息传递到上个界面的button

self.sureButton = [[UIButton alloc]initWithFrame:CGRectMake(self.addressLabel.frame.origin.x + self.addressLabel.frame.size.width, 0,self.messageView.frame.size.width - self.addressLabel.frame.origin.x - self.addressLabel.frame.size.width, 40)];

[self.messageView addSubview:self.sureButton];

self.sureButton.backgroundColor = [UIColor colorWithHex:0x2ecb7d];

[self.sureButton setTitle:@"确定" forState:UIControlStateNormal];

self.sureButton.titleLabel.font = [UIFont systemFontOfSize:13.0f];

[self.sureButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];

[self.sureButton addTarget:self action:@selector(sureButtonClick:) forControlEvents:UIControlEventTouchUpInside];

[self.mapView addSubview:self.messageView];

[self.mapView addSubview:self.locationView];

}

/**
*用户位置更新后，会调用此函数
*@param userLocation 新的用户位置
*/
- (void)didUpdateBMKUserLocation:(BMKUserLocation *)userLocation{

BMKCoordinateRegion region;

region.center.latitude  = userLocation.location.coordinate.latitude;
region.center.longitude = userLocation.location.coordinate.longitude;
region.span.latitudeDelta = 0;
region.span.longitudeDelta = 0;

NSLog(@"当前的坐标是:%f,%f",userLocation.location.coordinate.latitude,userLocation.location.coordinate.longitude);

[_mapView updateLocationData:userLocation];
[_locService stopUserLocationService];//取消定位  这个一定要写，不然无法移动定位了
_mapView.centerCoordinate = userLocation.location.coordinate;
NSLog(@" _mapView.centerCoordinate------%f-----%f", _mapView.centerCoordinate.latitude, _mapView.centerCoordinate.longitude);
[self createLocationSignImage];

}

//确定按钮的点击

- (void)sureButtonClick:(UIButton *)button{

if([self.chosseAddressDelegate respondsToSelector:@selector(chosseAddressBack:name:point:)]){
[self.chosseAddressDelegate chosseAddressBack:self.addressLabel.text name:self.name point:self.location2D];
}
[self.navigationController popViewControllerAnimated:YES];
}

- (void)mapView:(BMKMapView *)mapView annotationViewForBubble:(BMKAnnotationView *)view{
NSLog(@"点击了");
CLLocationCoordinate2D pt=(CLLocationCoordinate2D){0,0};
pt=(CLLocationCoordinate2D){mapView.region.center.latitude,mapView.region.center.longitude};
BMKReverseGeoCodeOption * option = [[BMKReverseGeoCodeOption alloc]init];
option.reverseGeoPoint = pt;
BOOL flag=[_searchAddress reverseGeoCode:option];

if (flag) {
//        _mapView.showsUserLocation=NO;//不显示自己的位置

}
}

//地图被拖动的时候，需要时时的渲染界面，当渲染结束的时候我们就去定位然后获取图片对应的经纬度

- (void)mapView:(BMKMapView *)mapView onDrawMapFrame:(BMKMapStatus*)status{
NSLog(@"onDrawMapFrame");
}

- (void)mapView:(BMKMapView *)mapView regionWillChangeAnimated:(BOOL)animated{
NSLog(@"regionWillChangeAnimated");
}

- (void)mapView:(BMKMapView *)mapView regionDidChangeAnimated:(BOOL)animated{
NSLog(@"regionDidChangeAnimated");

CGPoint touchPoint = self.locationView.center;

CLLocationCoordinate2D touchMapCoordinate =
[self.mapView convertPoint:touchPoint toCoordinateFromView:self.mapView];//这里touchMapCoordinate就是该点的经纬度了
NSLog(@"touching %f,%f",touchMapCoordinate.latitude,touchMapCoordinate.longitude);

BMKReverseGeoCodeOption * option = [[BMKReverseGeoCodeOption alloc]init];
option.reverseGeoPoint = touchMapCoordinate;
BOOL flag=[_searchAddress reverseGeoCode:option];

if (flag) {
//        _mapView.showsUserLocation=NO;//不显示自己的位置
}
}

//定位自己的位置
- (IBAction)locationButtonClick:(UIButton *)sender {

[_locService startUserLocationService];
_mapView.showsUserLocation = NO;//先关闭显示的定位图层
_mapView.userTrackingMode = BMKUserTrackingModeNone;//设置定位的状态
_mapView.showsUserLocation = YES;//显示定位图层
}

//点击地图的空白区域

- (void)mapView:(BMKMapView *)mapView onClickedMapBlank:(CLLocationCoordinate2D)coordinate{

NSLog(@"onClickedMapBlank-latitude==%f,longitude==%f",coordinate.latitude,coordinate.longitude);
}

//点击地图中的背景有标记的区域

- (void)mapView:(BMKMapView *)mapView onClickedMapPoi:(BMKMapPoi *)mapPoi{
NSLog(@"点击onClickedMapPoi---%@",mapPoi.text);

CLLocationCoordinate2D coordinate = mapPoi.pt;
//长按之前删除所有标注
NSArray *arrayAnmation=[[NSArray alloc] initWithArray:_mapView.annotations];
[_mapView removeAnnotations:arrayAnmation];
//设置地图标注
BMKPointAnnotation* annotation = [[BMKPointAnnotation alloc]init];
annotation.coordinate = coordinate;
annotation.title = mapPoi.text;
[_mapView addAnnotation:annotation];
BMKReverseGeoCodeOption *re = [[BMKReverseGeoCodeOption alloc] init];
re.reverseGeoPoint = coordinate;
[SVProgressHUD show];
[_searchAddress reverseGeoCode:re];
BOOL flag =[_searchAddress reverseGeoCode:re];
if (!flag){
NSLog(@"search failed!");
}
}

//根据经纬度返回点击的位置的名称
-(void)onGetReverseGeoCodeResult:(BMKGeoCodeSearch *)searcher result:(BMKReverseGeoCodeResult *)result errorCode:(BMKSearchErrorCode)error{

[SVProgressHUD dismiss];
NSString * resultAddress = @"";
NSString * houseName = @"";

CLLocationCoordinate2D  coor = result.location;

if(result.poiList.count > 0){
BMKPoiInfo * info = result.poiList[0];
if([info.name rangeOfString:@"-"].location != NSNotFound){
houseName = [info.name componentsSeparatedByString:@"-"][0];
}else{
houseName = info.name;
}
resultAddress = [NSString stringWithFormat:@"%@%@",result.address,info.name];
}else{
resultAddress =result.address;
}

if(resultAddress.length == 0){
self.addressLabel.text = @"位置解析错误，请拖动重试！";
return;
}

self.addressLabel.text = resultAddress;

self.location2D = coor;
self.name = houseName;
}

//点击一个大头针

- (void)mapView:(BMKMapView *)mapView didSelectAnnotationView:(BMKAnnotationView *)view{
NSLog(@"点击didSelectAnnotationView-");
}

/**
*在地图View将要启动定位时，会调用此函数
*@param mapView 地图View
*/
- (void)willStartLocatingUser
{
NSLog(@"start locate");
}

/**
*用户方向更新后，会调用此函数
*@param userLocation 新的用户位置
*/
- (void)didUpdateUserHeading:(BMKUserLocation *)userLocation
{
[_mapView updateLocationData:userLocation];
NSLog(@"heading is %@",userLocation.heading);
}

/**
*在地图View停止定位后，会调用此函数
*@param mapView 地图View
*/
- (void)didStopLocatingUser
{
NSLog(@"stop locate");
}

/**
*定位失败后，会调用此函数
*@param mapView 地图View
*@param error 错误号，参考CLError.h中定义的错误号
*/
- (void)didFailToLocateUserWithError:(NSError *)error
{
NSLog(@"location error");
}

- (void)dealloc {

if (_mapView) {
_mapView = nil;
}
}

- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];

}

@end