Question

I have a method which calculates loan payments based on car price, interest rate and number of years, this method is in my model and is accessed through my main view controller.

I created a singleton in the model but since I created it the method that calculates the payments stopped working for some reason. I have made sure that I have created the shared instance, It was working before I implemented the singleton.

Any help would be appreciated. I have not received any errors.

Here is the singleton I created.

+(id) sharedCalculatorBrain
{
    static id sharedCalculatorBrain = nil;
    if (sharedCalculatorBrain == nil)
    {
        sharedCalculatorBrain = [[sharedCalculatorBrain alloc]init];
    }

    return sharedCalculatorBrain;
}

Here is how I have created the object.

CalculatorBrain * brain = [CalculatorBrain sharedCalculatorBrain];  

and I call the method by using:

[brain calculatePaymentPlan:[self.txtLoanAmount.text doubleValue] :[self.txtInterestRate.text doubleValue] :[self.txtNumberOfYears.text doubleValue]];

Answer 1

Not sure if it is a typo, but check your code if you allocate the singleton instance using:

sharedCalculatorBrain = [[sharedCalculatorBrain alloc] init];

Because if this is the case, you need to do:

sharedCalculatorBrain = [[CalculatorBrain alloc]init];

Hope this helps, good luck with your project!