Modify ContractorCalculator to display the tax rate. Use two Labels: one to display the text “Tax Rate:” and the other to display the current tax rate. Add a button “Change Rate” that will open a view controller that allows the user to enter the tax rate. Save the tax rate in a UserDefaults object. When the dialog is closed, the new tax rate should be displayed in the Label. The app should use this rate for calculations until it is changed. The tax rate should be loaded from the UserDefaults object anytime the app opens.
Sample Solution