Question

我的表象显示UIMapView。然后,我在本图中增加大量说明(800多个)。

问题在于,用户被迫等待一分钟或一分钟,而所有皮条都装着。而且,一旦所有800个床位都列在地图上,就会出现 app。

谁能建议我如何改进以下的法典?

谢谢。

#import "MapView.h"
#import "MapPlaceObject.h"


@implementation MapView
@synthesize mapViewLink, mapLocations, detail, failedLoad;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
    // Custom initialization
}
return self;
}

-(void)addPins
{

for (MapPlaceObject * info in mapLocations) {


    double latitude = info.longitude;
    double longitude = info.latitude;

    NSString * name = info.name;
    NSString * addressline = info.addressOne;
    NSString * postcode = info.postCode;

    NSString * addresscomma = [addressline stringByAppendingString:@", "];
    NSString * address = [addresscomma stringByAppendingString:postcode];

    CLLocationCoordinate2D coordinate;
    coordinate.latitude = latitude;
    coordinate.longitude = longitude;
    MyLocation *annotation = [[[MyLocation alloc] initWithName:name address:address coordinate:coordinate] autorelease];


    [mapViewLink addAnnotation:annotation];

}
}

- (void)showLinks : (id)sender {


if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
    detail = [[DetailViewController alloc] initWithNibName:@"DetailViewController-iPad" bundle:nil];
} 

else if (!detail) {

    NSLog(@"Detail is None");

    detail = [[DetailViewController alloc] initWithNibName:@"DetailViewController" bundle:nil]; 

}

int uniqueID = ((UIButton *)sender).tag;

//PlaceObject *info = [mapLocations objectAtIndex:uniqueID];

detail.UniqueID = uniqueID;
detail.hidesBottomBarWhenPushed = YES;

[self.navigationController pushViewController:detail animated:YES];

self.detail = nil;

[detail release];

}

- (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>) annotation{

if (annotation == mapView.userLocation){
    return nil; //default to blue dot
}    

MKPinAnnotationView *annView=[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"currentloc"];
annView.pinColor = MKPinAnnotationColorRed;

nameSaved = annotation.title;

for (PlaceObject * info in mapLocations) {

    if (info.name == nameSaved) {

        saveID = info.UniqueID;

    }
}

UIButton *advertButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
advertButton.frame = CGRectMake(0, 0, 23, 23);
advertButton.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
advertButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentCenter;

[advertButton addTarget:self action:@selector(showLinks:) forControlEvents:UIControlEventTouchUpInside];

advertButton.tag = saveID;

annView.rightCalloutAccessoryView = advertButton;

annView.animatesDrop=TRUE;
annView.canShowCallout = YES;
annView.calloutOffset = CGPointMake(-5, 5);
return annView;

}

- (void)dealloc
{
[mapViewLink release];
[mapLocations release];
[detail release];
self.failedLoad = nil;
[failedLoad release];
[super dealloc];
}

- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn t have a superview.
[super didReceiveMemoryWarning];

// Release any cached data, images, etc that aren t in use.
}

- (void)viewWillAppear:(BOOL)animated {

if (firstTime) {

    CLLocationCoordinate2D zoomLocation;

    zoomLocation.latitude = 51.50801;
    zoomLocation.longitude = -0.12789;

    MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(zoomLocation, 15*METERS_PER_MILE, 15*METERS_PER_MILE);

    MKCoordinateRegion adjustedRegion = [mapViewLink regionThatFits:viewRegion];                

    [mapViewLink setRegion:adjustedRegion animated:YES];  

    firstTime = NO;

}    
}

- (void)viewDidLoad
{
[super viewDidLoad];

firstTime = YES;

failedLoad = [[NSMutableArray alloc]init];

self.mapLocations = [BluePlaqueDatabase database].mapInfo;

[self addPins];
}

- (void)viewDidUnload
{
[mapViewLink release];
mapViewLink = nil;
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}

Answer 1

你可以在此作的两个最大速度改进是:

Implement annotation view re-use (right now it creates a new view every time it needs to show an annotation even if the same one comes into view again.
Change how the UniqueID is set. To set it, the code is currently looping through all the annotations every time it creates an annotation view (which could happen any time the map view is zoomed or scrolled--not just the initial time).

首先,不寻求在<条码>上查询>,而是使用一个纽扣标记通过通知识别符号addcode>UniqueID,将其作为一项财产列入你的习惯说明类别 MyLocation,并在<条码>中添加说明本身时确定该财产:

annotation.uniqueID = info.UniqueID;  // <-- give id to annotation itself
[mapViewLink addAnnotation:annotation];

您还可以在<条码>上添加<>uniqueID,作为“条码>的参数,而不是单独分配财产。

Next, to implement annotation view re-use, the viewForAnnotation method should look like this:

- (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>) annotation{

    if (annotation == mapView.userLocation){
        return nil; //default to blue dot
    }    

    NSString *reuseId = @"StandardPin";
    MKPinAnnotationView *annView = (MKPinAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:reuseId];
    if (annView == nil)
    {
        annView = [[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:reuseId] autorelease];

        annView.pinColor = MKPinAnnotationColorRed;
        annView.animatesDrop = YES;
        annView.canShowCallout = YES;
        annView.calloutOffset = CGPointMake(-5, 5);

        UIButton *advertButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
        advertButton.frame = CGRectMake(0, 0, 23, 23);
        advertButton.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
        advertButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentCenter;

        annView.rightCalloutAccessoryView = advertButton;
    }
    else
    {
        //update the annotation property if view is being re-used...
        annView.annotation = annotation;
    }

    return annView;
}

Finally, to respond to the button press and figure out which UniqueID to show the detail for, implement the calloutAccessoryControlTapped delegate method:

- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)view 
            calloutAccessoryControlTapped:(UIControl *)control
{
    MyLocation *myLoc = (MyLocation *)view.annotation;

    int uniqueID = myLoc.uniqueID;

    NSLog(@"calloutAccessoryControlTapped, uid = %d", uniqueID);

    //create, init, and show the detail view controller here...
}

After all these changes, only the initial loading of the annotations will take up most of the time. If that is still a problem, one solution is to only add annotations that would be visible in the currently displayed region and add/remove annotations as the user changes the visible region.

Answer 2

我完全同意安娜。但认为,800项通知书同时将导致极差的接口。因此,如果你们的地图应当提供用户互动,如滚动或把你聚集在一起,就能更好地落实您的认知。

友情链接