propertyHistory.md

propertyHistory

propertyHistory allows you to observe when a property of your element was last changed. It also allows you to undo/redo changes to the property.

Usage

class MyElement extends LitElement {
  @property({type: String})
  public someProp = 'foo';

  constructor() {
    super();

    this._propHistoryCtrl = new PropertyHistoryController(
      this,
      'someProp'
    );
  }

  render() {
    return html`
      someProp was last changed at ${this._propHistoryCtrl.lastChanged}.
    `;
  }
}

Options

N/A

Methods

There are two methods available:

• undo
• redo

There's a maximum of 4 versions of the property's value kept in memory. This means you can only undo a maximum of 4 times, or if you already did that, you can only redo a maximum of 4 times.

undo()

Calling this will revert the property to its previous value.

redo()

Calling this will restore a value you previous reverted.