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];
[