addTag method

void addTag(bool duplicate, String tag, BuildContext context)

Adds a new tag to the tag list.

Performs comprehensive validation including:

• Empty tag checking
• Duplicate validation (based on duplicate parameter and widget settings)
• Maximum tag limit enforcement
• Custom tag validation using TagField.tagValidator

If validation fails, shows appropriate error messages via ScaffoldMessenger. On successful addition, notifies listeners and triggers callbacks.

Parameters:

• duplicate: Whether to allow duplicate tags for this operation
• tag: The tag string to add
• context: The BuildContext for showing error messages

Example:

notifier.addTag(false, 'flutter', context);

Implementation

void addTag(bool duplicate, String tag, BuildContext context) {
  if (tag.isEmpty) return;

  String processedTag = _processTag(tag);
  if (processedTag.isEmpty) return;
  // Check for duplicates
  if (!duplicate && _isDuplicate(processedTag)) {
    if (!widget.allowDuplicates) {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('Duplicate tags are not allowed')),
      );
      return;
    }
    // If duplicates are allowed, proceed without further checks
  }

  // Check max tags limit
  if (widget.maxTags != null && _tags.length >= widget.maxTags!) {
    ScaffoldMessenger.of(context).showSnackBar(
      const SnackBar(content: Text('Maximum tag limit reached')),
    );
    return;
  }

  // Validate tag
  if (widget.tagValidator != null) {
    final validationError = widget.tagValidator!(processedTag);
    if (validationError != null) {
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(SnackBar(content: Text(validationError)));
      return;
    }
  }

  _tags.add(processedTag);
  notifyListeners();

  widget.onTagAdded?.call(processedTag);
  widget.onTagsChanged?.call(_tags);
}