问向烛台图表添加多个注释

EN

//the image to display 
UIImage *flag = [UIImage imageNamed:@"flag.png"];
CPTImage *flagImage = [CPTImage imageWithCGImage:flag.CGImage
                                           scale:flag.scale];

CPTBorderedLayer *borderedLayer = [[CPTBorderedLayer alloc] init];

CPTMutableLineStyle *blackLineStyle = [CPTMutableLineStyle lineStyle];
[blackLineStyle setLineColor:[CPTColor blackColor]];
[blackLineStyle setLineWidth:1.0f];

[borderedLayer setBorderLineStyle:blackLineStyle];

[borderedLayer setFill:[CPTFill fillWithImage:flagImage]];

//the 'i' in the next statement is from a 'for' loop iterating over NSArrays: xCoordinates & yCoordinates, containing the corresponding coordinates for short-listed data points
NSArray *anchorPoint = [NSArray arrayWithObjects:[xCoordinates objectAtIndex:i], [yCoordinates objectAtIndex:i], nil];

CPTPlotSpaceAnnotation *alertAnnotation = [[CPTPlotSpaceAnnotation alloc] initWithPlotSpace:[[[self hostView] hostedGraph] defaultPlotSpace]
                                                                                anchorPlotPoint:anchorPoint];
[alertAnnotation setContentLayer:borderedLayer];
[alertAnnotation setDisplacement:CGPointMake(0.0f, 10.0f)];

[[[[self hostView] hostedGraph] plotAreaFrame] addAnnotation:alertAnnotation];