1.block使用步骤:
1>.有两个控制器,主动传值或者提供方法的控制器A,接受值的控制器B
2>.让A控制器typedef void(^myBlock)(),然后copy一个myBlock类型的属性:
@property(nonatomic ,copy) myBlock block;
3>.在B控制器中创建A控制器,然后调用A控制器的方法
4>.在A控制器方法中,记录block:self.block = block;
5>.在合适的地方调用block:self.block(poiResultList.poiInfoList);
6>.调用以后block参数里边已经有值,这个时候在B控制器中调用A控制器的方法中参数block开始执行,并且block中参数也已经有值.
2.block原理篇:
1>.谁要传值,谁声明和定义block以及把block作为参数的方法
2>.传值方记录下来block,在合适的时候调用
3>.接受值方,调用方法,等传值方调用block的时候才会在代码块中拿到block传过来的参数值.
3.demo
#import"TSYBaiduTool.h"
@interfaceTSYBaiduTool()
@property(nonatomic,copy) Blockblock;
/** poi检索对象*/
@property(nonatomic,strong)BMKPoiSearch*searcher;
@end
@implementationTSYBaiduTool
single_implementation(TSYBaiduTool)
- (void)getPoiWithCeneter:(CLLocationCoordinate2D)centerkey:(NSString*)key Result:(Block)block{
//记录block self.block=block;
//初始化检索对象 _searcher=[[BMKPoiSearch alloc] init];
_searcher.delegate=self;
//发起检索
BMKNearbySearchOption*option = [[BMKNearbySearchOption alloc] init];
option.pageIndex=0; option.pageCapacity=20; option.location= center; option.keyword= key;
BOOLflag = [_searcherpoiSearchNearBy:option];
if(flag){NSLog(@"周边检索发送成功");}else
{NSLog(@"周边检索发送失败");}
#import"TSYBaiduTool.h"
@interfaceTSYBaiduTool()
@end
@implementationTSYBaiduTool
- (void)addAnnotationCenter:(CLLocationCoordinate2D)centertitle:(NSString*)title subTitle:(NSString*)subTile toMapView:(BMKMapView*)mapView{
//添加一个PointAnnotation
BMKPointAnnotation* annotation = [[BMKPointAnnotation alloc] init];
annotation.coordinate= center;
annotation.title= title;
annotation.subtitle= subTile;
[mapViewaddAnnotation:annotation]; }
#import"TSYBaiduTool.h"
@interfaceTSYBaiduTool()
@end
@implementationTSYBaiduTool
#pragmamark - BMKPoiSearchDelegate
//实现PoiSearchDeleage处理回调结果
-(void)onGetPoiResult:(BMKPoiSearch*)searcherresult:(BMKPoiResult*)poiResultListerrorCode:(BMKSearchErrorCode)error{
if(error ==BMK_SEARCH_NO_ERROR) {
//在此处理正常结果
self.block(poiResultList.poiInfoList);
} else if(error ==BMK_SEARCH_AMBIGUOUS_KEYWORD){
//当在设置城市未找到结果，但在其他城市找到结果时，回调建议检索城市列表
//result.cityList; NSLog(@"起始点有歧义"); }else{
NSLog(@"抱歉，未找到结果--%zd", error);}
}
@end
#import"Singleton.h"
#import typedef void(^Block) (NSArray*result);
@interfaceTSYBaiduTool :NSObject
single_interface(TSYBaiduTool)
-(void)getPoiWithCeneter:(CLLocationCoordinate2D)centerkey:(NSString*)key Result:(Block)block;
-(void)addAnnotationCenter:(CLLocationCoordinate2D)centertitle:(NSString*)title subTitle:(NSString*)subTile toMapView:(BMKMapView*)mapView;
@end
#import"ViewController.h"
#import"TSYBaiduTool.h"
@interfaceViewController()
@property(weak,nonatomic) IBOutlet BMKMapView*mapView;
@end
@implementationViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.mapView.delegate=self;
}
#pragmark - BMKMapViewDelegate
/**
*长按地图时调用
* @param mapView 地图
* @param coordinate点对应的经纬度
*/
-(void)mapview:(BMKMapView*)mapView onLongClick:(CLLocationCoordinate2D)coordinate{
//调整地图显示区域
BMKCoordinateSpanspan = BMKCoordinateSpanMake(0.075418,0.051922);
BMKCoordinateRegionregion = BMKCoordinateRegionMake(coordinate, span);
[mapViewsetRegion:regionanimated:YES];
//poi检索
[[TSYBaiduToolsharedTSYBaiduTool]getPoiWithCeneter:coordinatekey:@"小吃"Result:^(NSArray *result) {
[resultenumerateObjectsUsingBlock:^(BMKPoiInfo*_Nonnullobj,NSUIntegeridx,BOOL*_Nonnullstop) {
//添加大头针
[[TSYBaiduToolsharedTSYBaiduTool]addAnnotationCenter:obj.pttitle:obj.namesubTitle:obj.addresstoMapView:self.mapView];
}];
}];
}
@end