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alertHook

Syntax

    the alertHook

Description

System property; specifies a parent script that contains the `on alertHook` handler. Use `alertHook` to control the display of alerts about file errors or Lingo script errors. When an error occurs and a parent script is assigned to `alertHook`, Director runs the `on alertHook` handler in the parent script.

Although it is possible to place `on alertHook` handlers in movie scripts, it is strongly recommended that you place an `on alertHook` handler in a behavior or parent script to avoid unintentionally calling the handler from a wide variety of locations and creating confusion about where the error occurred.

Because the `on alertHoo`k handler runs when an error occurs, avoid using the `on alertHook` handler for Lingo that isn't involved in handling an error. For example, the `on alertHook` handler is a bad location for a `go to movie` statement.

The o`n alertHook` handler is passed an instance argument and two string arguments that describe the error. Depending on the Lingo within it, the `on alertHook` handler can ignore the error or report it in another way.

Example

The following statement specifies that the parent script Alert is the script that determines whether to display alerts when an error occurs. If an error occurs, Lingo assigns the error and message strings to the field cast member Output and returns the value 1.

    on prepareMovie
    	the alertHook = script "Alert"
    end

    -- parent script "Alert"
    on alertHook me, err, msg
    	member("Output").text = err && msg
    	return 1
    end