How do I draw the line chart with unpontinuous numbers in iOS Charts?

I'm working on drawing the line chart with data like: [50,40,60,-,80,-,70,10] and couldn't figure out how I draw the line for these data.

"-" means no value, not zero.

Guessed that Charts would accept nil for it, but it doesn't.

Please let me know if you have the answer for this.

Thank you in advance.

Start by checking the iOS Charts line-chart APIs and documentation for how the sample data [50,40,60,-,80,-,70,10] represents missing values. Done means identifying a supported way to leave gaps in the line, or documenting that this input is not supported and what limitation remains.

Written by the indexing model from the issue text.