public FormInputValidator fileExists (VisValidatableTextField field, FileHandle relativeTo, String errorMsg) {
		FileExistsValidator validator = new FileExistsValidator(relativeTo.file(), errorMsg);
		field.addValidator(validator);
		add(field);
		return validator;

	}
public FormInputValidator fileExists ( VisValidatableTextField field , FileHandle relativeTo , String errorMsg ) { FileExistsValidator validator = new FileExistsValidator ( relativeTo . file ( ) , errorMsg ) ; field . addValidator ( validator ) ; add ( field ) ; return validator ; }
Validates if relative path entered in text field points to an existing file.
@param relativeTo path of this file is used to create absolute path from entered in field (see {@link FileExistsValidator}).