How create DataSource for my class like UITableDataSource?

Question

I have a class GraphView(xib + class). Chart view with labels and other UI elements. I need to create DataSource protocol for this class it was realized in UITableView, as UITableDataSource. That needs for more comfortable working with data, which I want load to my GraphView.

If you know how do this or have link to this question solution, please help me. Thanks for all questions!

Answer 1

Creating a custom DataSource works just like a Delegate pattern.

protocol GraphViewDataSource: class {
  func numberOfRow(for graph: GraphView) -> Int
}

class GraphView {
  weak var dataSource: GraphViewDataSource?

  init() {
    let numberOfRow = dataSource?.numberOfRow(for: self)
  }
}

Note: Don't forget to set your dataSource property to weak to avoid reference cycle (this is why GraphViewDataSource need to be constrained to class).