How do I display one (1) plotSymbol in a scatter plot?

Question

Environment: iOS 5.1 Scenario: 1-2 scatter/linear plots without any symbols.

I need to display only one (1) symbol where the user had touched upon a scatter plot. The rest of the plot doesn't have any symbols.

I understand a symbol represents a data point. But I need to graph all the data points... just set one (1) point/index to display its symbol per user-touch; hopefully to toggle on/off.

Regards, Ric.

Answer 1

Use the -symbolForScatterPlot:recordIndex: datasource method. Return a plot symbol for the index that you want highlighted and [NSNull null] for the others. Call -reloadData on the plot when you need to change the highlighted index.