ios - 将图像从 Google Places Photo JSON 返回到 imageView

Question

我希望从 Google places API 获取照片，并将它们存储到 URL 或图像中，以便在单独的 View Controller 中显示给用户。

似乎照片 json 为每个位置返回了这个:

    photos =  (
                {
                   height = 466;
                   "html_attributions" = ();
                   "photo_reference" = "CnRnAAAAgBUy_mqt9WglYJvS2v8XBfw5ER1U8Wn7DWvfoWI4P78w8_ZAsLQeFSYescNYE1NVgkV50jJE7SYBxdZuOmGP4jWGyCLobCd2nyEDbeB9lg1JU7KYV0o57i-OQTROIwj9ZwzWG03aUOypMjA_7fXD8BIQqbC5J0daROt_LqztWmz-xhoU20meJb50VyAE-zqkp9Jzu1Fegfs";
                   width = 695;
                }
             );

根据 Google Places Photo 文档，它说:

https://developers.google.com/places/documentation/photos

无法找到能够从 json 中获取此内容并将其存储为字符串的示例，因为 url 不是图像或任何内容的直接链接。

编辑:出现错误

[__NSCFArray objectForKey:]: unrecognized selector sent to instance 0x13258510
 *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFArray objectForKey:]: unrecognized selector sent to instance 0x13258510'

更新代码:

-(void)plotPositions:(NSArray *)data {

    for (id<MKAnnotation> annotation in _mapView.annotations) {
        if ([annotation isKindOfClass:[MapPoint class]]) {
            [_mapView removeAnnotation:annotation];
        }
    }
    //  Loop through the array of places returned from the Google API.
    for (int i=0; i<[data count]; i++) {

        NSDictionary* place = [data objectAtIndex:i];

        NSDictionary *geo = [place objectForKey:@"geometry"];

        NSDictionary *loc = [geo objectForKey:@"location"];

        // Getting Photo Reference Details - ADDED NOW RECIEVING ERROR?
        NSDictionary *photoDict = [place objectForKey:@"photos"];
        NSString *photoRef = [photoDict objectForKey:@"photo_reference"];

         NSString *url = [NSString stringWithFormat:@"https://maps.googleapis.com/maps/api/place/photo?photoreference=%@&key=%@&sensor=false&maxwidth=320", photoRef, kGOOGLE_API_KEY];

        NSLog(@"TESTING: %@", url);


        NSString *name=[place objectForKey:@"name"];
        NSString *vicinity=[place objectForKey:@"vicinity"];


        CLLocationCoordinate2D placeCoord;
        placeCoord.latitude=[[loc objectForKey:@"lat"] doubleValue];
        placeCoord.longitude=[[loc objectForKey:@"lng"] doubleValue];

        MapPoint *placeObject = [[MapPoint alloc] initWithName:name address:vicinity rating:rating coordinate:placeCoord];

        [_mapView addAnnotation:placeObject];
    }
}

Answer 1

JSON 中的 photo_reference 属性是一个参数，您可以将其用作发出照片请求的参数。

在您引用的 url ( https://developers.google.com/places/documentation/photos ) 中，请特别查看“放置照片请求”部分，以正确的方式实际构建将请求图像的 url。

根据您上面的代码，您没有处理返回的照片数组。假设您想要第一张照片:

NSDictionary *photoDict = [[place objectForKey:@"photos"] objectAtIndex:0];
NSString *photoRef = [photoDict objectForKey:@"photo_reference"];

NSString *url = [NSString stringWithFormat:@"https://maps.googleapis.com/maps/api/place/photo?photoreference=%@&key=%@&sensor=false&maxwidth=320", photoRef, kGOOGLE_API_KEY];