F > FCheckBox.setChangeHandler |  |

FCheckBox.setChangeHandler

FCheckBox, FCheckBox.setChangeHandler, setChangeHandler

Availability

Flash Player 6.

Usage

    myCheckBox.setChangeHandler(functionName, [location])

Parameters

`functionName` A string specifying the name of the handler function to execute when the value of the check box changes. If the `location` parameter is not specified, this function must be in the same Timeline as the component instance.

`location` A path reference to a data object, movie clip, or Timeline that contains the specified function. This parameter is optional and defaults to the parent Timeline of the component.

Returns

Nothing.

Description

Method; specifies a change handler to call when the value of the check box changes. You can specify the same change handler function for more than one component; the function always accepts the instance of the component that has changed as a parameter. Calling this method overrides the Change Handler parameter value specified in authoring.

For more information, see Writing change handler functions for components in the Using Components chapter of Using Flash.

Example

The following code specifies `myHandler` as the function called when the value of `checkBox1` changes. Because the `location` parameter is not specified, `myHandler` must be in the same Timeline as the component instance.

The `component` parameter in `myHandler` is automatically filled in with the instance of a component (the component that has changed as the result of user input and that specifies `myHandler` as its change handler). The actions defined in `myHandler` specify that when the user selects a check box, the name of the component and "has been selected" is written to the Output window.

    checkBox1.setChangeHandler("myHandler");
    function myHandler(component){
    trace(component._name + " has been selected ");
    }

If in the preceding example `myHandler` is a function located in the great-grandparent Timeline of the component's Timeline, the first line of code would be as follows:

    check1.setChangeHandler("myHandler", _parent._parent._parent);

The following code creates the function `myHandler` in an instance of `myObject` (which is of class Object), and then specifies `myHandler` as the function for `check1`.

    myObject = new Object();
    myObject.myHandler = function(component){
    trace(component._name + " has been selected ");
    }
    check1.setChangeHandler("myHandler", myObject);