Question

I have an xml file that contains a structure.. In this structure, I have Actions node. So under Actions node, there are multiple “Action” nodes that each has Value and Name attributes.

e.g.

<?xml version="1.0" encoding="ISO-8859-1"?>

<Testcases SuiteName="CalculatorActions">

    <Testcase id="101" Name="testAddFunction">
        <Setup/>
        <TearDown/>
        <Test>
            <Action Name="Enter first operand" Type="input" Value="5"/>
            <Action Name="Enter second operand" Type="input" Value="3"/>
            <Action Name="Select operator" Type="input" Value="+"/>
            <Action Name="Click Calculator" Type="operation"/>
        </Test>
        <Validations>
            <Action Name="Validate result" Type="output" Value="8"/>
        </Validations>
    </Testcase>

</Testcases>

What I would like to do is; I want to map these actions to the methods that I have implemented in Objective-C.

Let’s say i have a class called; “CalculatorActions” and defined 5 methods inside. I would like to map the actions that i have in xml (text format) to the methods i created in CalculatorActions.

e.g.

@interface CalculatorActions : NSObject

// Property
@property (strong, nonatomic) NSString* actionScript;

// Actions
- (void)enterFirstOperand:(double)operand;

- (void)enterSecondOperand:(double)operand;

- (void)selectOperator:(NSString*)operator;

- (void)clickCalculate;

// Validations

-(void)validateResult:(NSString*)exptectedResult;

@end

so when i read the xml file, I would want to map the actions in xml file to the corresponding method in a class.

I think what i am looking for is something like;

@interface CalculatorActions

[Action("addOperand", "Enter first operand")]
- (void) addOperand:(double)operand1 ToOther:(double)operand2;

What would be the best way to do this?

Answer 1

You can create an NSInvocation instance, set the selector, arguments, and optionally capture the return value. You can create these all with strings.

e.g.

SEL mySelector = NSSelectorFromString(@"testAddFunction");
Class MyClass = NSClassFromString(@"CalculatorActions");
NSString *myArgument = @"5";

NSInvocation *myInvocation = [NSInvocation invocationWithMethodSignature:[MyClass instanceMethodSignatureForSelector:mySelector]];
[invocation setTarget:myClass];
[invocation setSelector:mySelector];
[invocation setArgument:&myArgument atIndex:2];
[invocation invoke];

Note – the setArgument: selector takes a pointer address, and the index of the arguments start at 2.