The block in the Editor

The Block Editor is a React Single Page Application (SPA). Every block in the Editor is displayed through a React component defined in the edit property of the settings object used to register the block on the client.

The props object received by the block’s Edit React component includes:

  • attributes: An object of all the block’s attributes.
  • setAttributes: A method to update the attributes object.
  • isSelected: A boolean value that communicates whether the block is currently selected

WordPress provides many built-in standard components that can be used to define the block interface in the Editor. These built-in components are available via packages such as @wordpress/components and @wordpress/block-editor.

The WordPress Gutenberg project uses Storybook to document the user interface components that are available in WordPress packages.

Custom settings controls for the block in the Block Toolbar or the Settings Sidebar can also be defined through this Edit React component via built-in components such as:

Built-in components

The package @wordpress/components includes a library of generic WordPress components to create common UI elements for the Block Editor and the WordPress dashboard. Some of the most commonly used components from this package are:

The package @wordpress/block-editor includes a library of components and hooks for the Block Editor, including those to define custom settings controls for the block. Some of the components most commonly used from this package are:

The package @wordpress/block-editor also provides the tools to create and use standalone block editors.

A good workflow when using a component for the Block Editor is:

  • Import the component from a WordPress package.
  • Add the corresponding code for the component to your project in JSX format.
  • Most built-in components will be used to set block attributes, so define any necessary attributes in block.json and create event handlers to update those attributes with setAttributes in your component.
  • Adapt the code to be serialized and stored in the database if needed.

Block Controls: Block Toolbar and Settings Sidebar

To simplify block customization and ensure a consistent user experience, there are several built-in UI patterns to help generate the Editor preview of a block.

The image below details the Block Toolbar and the Settings Sidebar of a selected Paragraph block.

Diagram showing the Block Toolbar and the Settings Sidebar when a Paragraph block is selected

Block Toolbar

When the user selects a block, a number of control buttons may be shown in a toolbar above the selected block. Some of these block-level controls may be included automatically, but you can also customize the toolbar to include controls specific to your block type. If the return value of your block type’s Edit function includes a BlockControls element, those controls will be shown in the selected block’s toolbar.

export default function Edit( { className, attributes: attr, setAttributes } ) {

    const onChangeContent = ( newContent ) => {
        setAttributes( { content: newContent } );

    const onChangeAlignment = ( newAlignment ) => {
        setAttributes( {
            alignment: newAlignment === undefined ? 'none' : newAlignment,
        } );

    return (
        <div { ...useBlockProps() }>
                        value={ attr.alignment }
                        onChange={ onChangeAlignment }

                className={ className }
                style={ { textAlign: attr.alignment } }
                onChange={ onChangeContent }
                value={ attr.content }

See the full block example of the code above.

Note that BlockControls is only visible when the block is currently selected and in visual editing mode. BlockControls are not shown when editing a block in HTML editing mode.

Settings Sidebar

The Settings Sidebar is used to display less-often-used settings or those that require more screen space. The Settings Sidebar should be used for block-level settings only and is shown when a block is selected.

If a setting only affects selected content inside a block, such as “bolding” text, do not place the setting inside the Settings Sidebar. Use a toolbar instead. The Settings Sidebar is displayed even when editing a block in HTML mode, so it should only contain block-level settings.

Similar to rendering a toolbar, if you include an InspectorControls component in the return value of your block type’s Edit function, those controls will be shown in the Settings Sidebar region.

export default function Edit( { attributes, setAttributes } ) {
    const onChangeBGColor = ( hexColor ) => {
        setAttributes( { bg_color: hexColor } );

    const onChangeTextColor = ( hexColor ) => {
        setAttributes( { text_color: hexColor } );

    return (
        <div { ...useBlockProps() }>
            <InspectorControls key="setting">
                        <legend className="blocks-base-control__label">
                            { __( 'Background color', 'block-development-examples' ) }
                        <ColorPalette // Element Tag for Gutenberg standard colour selector
                            onChange={ onChangeBGColor } // onChange event callback
                        <legend className="blocks-base-control__label">
                            { __( 'Text color', 'block-development-examples' ) }
                            onChange={ onChangeTextColor }
                value={ attributes.message }
                onChange={ ( val ) => setAttributes( { message: val } ) }
                style={ {
                    backgroundColor: attributes.bg_color,
                    color: attributes.text_color,
                } }

See the full block example of the code above.

Block controls rendered in both the toolbar and sidebar will also be available when multiple blocks of the same type are selected.

For common customization settings, including color, border, spacing, and more, you can rely on block supports instead of a custom solution. Block supports provide a consistent UI with the same functionality as other Core blocks.

Additional resources