@blockly/continuous-toolbox

A Blockly plugin that creates a continuous-scrolling style toolbox/flyout that is always open. All of the blocks from all categories are in the flyout together, and the user can either click a category name in the toolbox or scroll to the category they're looking for. This flyout only works as a vertical flyout and it works in both left-to-right and right-to-left modes. Parts of the toolbox style have been changed already, but you can customize the style further by following the toolbox documentation.

The continuous toolbox is shown here with the 'Zelos' theme, and the style can be further customized.

Installation

Yarn

yarn add @blockly/continuous-toolbox

npm

npm install @blockly/continuous-toolbox --save

Usage

Import and call the registerContinuousToolbox() function before injecting Blockly. This style of flyout works best with a toolbox definition that does not use collapsible categories.

Note that this plugin uses APIs introduced in the v12 release of Blockly, so you will need to use at least this version or higher.

import * as Blockly from 'blockly';
import {registerContinuousToolbox} from '@blockly/continuous-toolbox';

// Inject Blockly.
registerContinuousToolbox();
const workspace = Blockly.inject('blocklyDiv', {
  toolbox: toolboxCategories,
  plugins: {
    flyoutsVerticalToolbox: 'ContinuousFlyout',
    metricsManager: 'ContinuousMetrics',
    toolbox: 'ContinuousToolbox',
  },
  // ... your other options here ...
});

Block Recycling

As a performance optimization, by default the continuous toolbox "recycles" blocks to avoid having to create DOM elements for potentially hundreds of blocks every time the flyout is shown. With the default set of blocks, this drops the time to show the flyout from roughly 35ms to 25ms; the effect is naturally larger with larger block sets.

Recycling is unrelated to Blockly's Trash feature; instead, it entails moving the blocks offscreen when the flyout is hidden, and then simply repositioning them when the flyout is shown again. Not all block types are amenable to this; in particular, blocks with dynamic behavior (e.g. those that reference variables, support mutations, or have dynamic dropdown fields) are excluded by default.

This feature can be toggled by calling setRecyclingEnabled() on an instance of ContinuousFlyout, and the default ruleset for determining which blocks are safe for recycling can be replaced with a custom callback by passing that function to setBlockIsRecyclable().

License

Apache 2.0