The upcoming December 2020 release includes API changes to Blockly UI Events. This change makes it easier to differentiate between UI events and creates better typing and property names.
Instead of firing Blockly.Events.Ui, we now fire more specific subclasses that inherit from Blockly.Events.BaseUi. For compatibility with developers who have extended Blockly.Events.Ui we have kept Blockly.Events.Ui with only minor changes. It now inherits from Blockly.Events.BaseUi.
If you have any questions, feel free to respond to this thread.
If you don’t do a lot with events, you can stop reading now. Otherwise, as part of upgrading to the newest release, you should expect to need to make the following changes anywhere that you listen to (or use) UI events:
You will need to change how you check for if an event is a Ui event.
As a result of this change, the type of all UI events are no longer ‘ui’ (with exception of deprecated Blockly.Events.Ui) and in order to check if an event is a UI event, you must use a new property on all events isUiEvent to check.
You will need to change the properties you access on UI events emitted from Blockly.
Additionally, the property names on UI Events have changed, to be more specific to what value they hold. Prior to this refactor, these events had the properties: element, oldValue, and newValue, where element held information on the more specific type of UI event. Now, the type property details the type of UI event and each event has its own set of properties.
Here is a detailed table of conversions for new events and properties: