blockly > Block > setOnChange
Block.setOnChange() method
Sets a callback function to use whenever the block's parent workspace changes, replacing any prior onchange handler. This is usually only called from the constructor, the block type initializer function, or an extension initializer function.
Signature:
setOnChange(onchangeFn: (p1: Abstract) => void): void;
Parameters
| Parameter |
Type |
Description |
| onchangeFn |
(p1: Abstract) => void |
The callback to call when the block's workspace changes. |
Returns:
void
Exceptions
{Error} if onchangeFn is not falsey and not a function.
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Last updated 2024-09-18 UTC.
[null,null,["Last updated 2024-09-18 UTC."],[[["The `setOnChange` method allows you to assign a callback function that executes whenever the block's parent workspace is modified."],["This method is typically called during the block's construction, initialization, or extension setup, replacing any existing `onchange` handler."],["The callback function receives an `Abstract` event object as input, providing information about the workspace change."],["It's crucial that the `onchangeFn` parameter is either a valid function or a falsey value to avoid runtime errors."]]],[]]
