getCurrentTimelineEntryForComplication

ComplicationController.m

#pragma mark - Timeline Population

- (void)getCurrentTimelineEntryForComplication:(CLKComplication *)complication withHandler:(void(^)(CLKComplicationTimelineEntry * __nullable))handler {
    
    ExtensionDelegate* myDelegate = (ExtensionDelegate*)[[WKExtension sharedExtension] delegate];
    
    if (complication.family == CLKComplicationFamilyModularSmall) {

        [myDelegate fetchRate:^(NSDictionary * data, NSError * _Nullable error) {

            Rate* rate = [data valueForKey:@"btc"];
            NSDate* now = [NSDate date];
            
            NSString* valueString = rate == nil ? @"?" : rate.value;

            CLKComplicationTemplateModularSmallStackText* textTemplate = [[CLKComplicationTemplateModularSmallStackText alloc] init];
            textTemplate.line1TextProvider = [CLKSimpleTextProvider
                                              textProviderWithText:@"BTC -> USD"
                                              shortText:@"BTC -> USD"];
            textTemplate.line2TextProvider = [CLKSimpleTextProvider
                                              textProviderWithText:valueString
                                              shortText:valueString];
            textTemplate.tintColor = [UIColor whiteColor];

            // Create the entry.
            CLKComplicationTimelineEntry* entry = nil;
            entry = [CLKComplicationTimelineEntry entryWithDate:now
                                           complicationTemplate:textTemplate];
    
            handler(entry);
        }];
        
    } 
        handler(nil);
    }
}