Vanilla javascript: Listening for changes on a class variable

Question

Is there any way to listen for changes to an instance variable in plain Javascript, and then have a method invoke on change?

I would like to update a table with this pattern, starting with this class:

class TableUpdater {
  tabledata;

  async setData(editedRow) {
    const response = await fetch('http://example.com/api', {
      method : 'post'
      , headers : {
        "Content-Type" : "application/json"
      }
      , body : JSON.stringify(editedRow)
    });

    const updatedData = await response.json();
    this.tabledata = updatedData;
  }

  async updateTable(arg1) {
    // can do the below, but it would be nice to decouple setData() from updateTable() 
    // await this.setData(arg1);

    // table creation logic
  }
}

const tableUpdater = new TableUpdater();

Answer 1

class TableUpdater {
  tabledata;
  listeners = [];

  onSetData(listener) {
    this.listeners.push(listener)
  }
  async setData(editedRow) {
    setTimeout((newData) => {
      for (let i = 0; i < this.listeners.length; i++) {
        this.listeners[i](newData)
      }
      this.tableData = newData
    }, 1000, [{
      foo: 'bar'

    }])
  }
}

const tableUpdater = new TableUpdater();
tableUpdater.onSetData(console.log)
tableUpdater.setData();