ICS3U1 Unit 1 Activity 4: Circumference Calculator

// This line makes the button, btnCalculate wait for a mouse click
// When the button is clicked, the displayCircleProperties function is called
btnCalculate.addEventListener(MouseEvent.CLICK, displayCircleProperties);

// This line makes the textinput, txtinRadius wait for a mouse click
// When the textinput is clicked, the clearLabels function is called
txtinRadius.addEventListener(MouseEvent.CLICK, clearLabels);

// This is the displayCircleProperties function
// e:MouseEvent is the click event experienced by the button
// void indicates that the function does not return a value
function displayCircleProperties(e:MouseEvent):void
{
    // declare the constants
    const PI:Number = 3.14159;

    // declare the variables
    var radius:Number;
    var area:Number;
    var circumference:Number;

    // calculate the area and circumference of a circle
    radius = Number(txtinRadius.text);
    area = PI * radius * radius;
    circumference = 2 * PI * radius;

    // put the values into the labels
    lblArea.text = area.toFixed(2);
    lblCircumference.text = circumference.toFixed(2);
}

// This is the clearLabels function
// e:MouseEvent is the click event experienced by the textinput
// void indicates that the function does not return a value
function clearLabels(e:MouseEvent):void
{
txtinRadius.text = "";
lblArea.text = "";
lblCircumference.text = "";
}