addSection method

void addSection({ required MessageBuilder builder, Button? button, Thumbnail? thumbnail, })

Adds a section to the message.

A section is a top-level layout component that allows you to contextually associate text content with an optional accessory component (either a button or a thumbnail). Sections are useful for organizing related content with interactive or visual elements.

The section's builder should contain only text components. The optional accessory can be either a button or a thumbnail, but not both.

Example:

// Section with text only
builder.addSection(
  builder: MessageBuilder()
    ..addText('## Important Notice')
    ..addText('Please read this carefully.'),
);

// Section with text and button accessory
builder.addSection(
  builder: MessageBuilder()
    ..addText('**New Feature Available**')
    ..addText('Click to learn more about our latest update.'),
  button: MessageButton.link('https://example.com', label: 'Learn More'),
);

// Section with text and thumbnail accessory
builder.addSection(
  builder: MessageBuilder()
    ..addText('## User Profile')
    ..addText('John Doe - Senior Developer'),
  thumbnail: Thumbnail(
    MediaItem.fromNetwork('https://example.com/avatar.png'),
  ),
);

Throws:

• FormatException if the section contains non-text components
• FormatException if both button and thumbnail are provided

See also:

• addContainer for general-purpose containers that support any component type
• Section for section configuration details
• Button for button types and options
• Thumbnail for thumbnail accessory options

Implementation

void addSection({
  required MessageBuilder builder,
  Button? button,
  Thumbnail? thumbnail,
}) {
  for (final component in builder._components) {
    if (component is! TextDisplay) {
      throw FormatException('Section components must be text only');
    }
  }

  _components.add(Section(
    builder: builder,
    button: button,
    thumbnail: thumbnail,
  ));
}