Question

I want to create a hover/tap effect on the symbol that was tapped, is this possible? Can’t find any documentation anyway indicating that it is?

Thanks

Answer 1

You can use this delegate method and add an annotation,

- (void)scatterPlot:(CPTScatterPlot *)plot plotSymbolWasSelectedAtRecordIndex:(NSUInteger)index {  
}

Create an annotation and add to graph in this delegate.

For eg:-

    CPTLayerAnnotation *annot = [[CPTLayerAnnotation alloc]initWithAnchorLayer:graph];
    CPTBorderedLayer * logoLayer = [[(CPTBorderedLayer *) [CPTBorderedLayer alloc] initWithFrame:CGRectMake(10,10,100,50)] autorelease]; 
    CPTFill *fillImage = [CPTFill fillWithImage:[CPTImage imageForPNGFile:@"whatEver!"]]; 
    logoLayer.fill = fillImage; 
    annot.contentLayer = logoLayer; 
    annot.rectAnchor=CPTRectAnchorTop;
    [graph addAnnotation:annot];

Check this for more details. Also check this. Sample code could be there in their demo apps.

Implement the symbolForScatterPlot:recordIndex: method to customize the plot symbol at each point. Return nil if you don’t want a symbol drawn at the given index. Once the user taps and the above delegate is called, probably you can call reloadData on plot and return the highlighted plotsymbols here. Check this.