Shared event handler (https://stackoverflow.com/a/57694729/5846045)

<!DOCTYPE html>
<html style="height: 100%;">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width,initial-scale=1.0" />
    <title>Demo</title>
    <script
      id="sap-ui-bootstrap"
      src="https://sdk.openui5.org/resources/sap-ui-core.js"
      data-sap-ui-libs="sap.ui.core,sap.m"
      data-sap-ui-theme="sap_horizon_dark"
      data-sap-ui-async="true"
      data-sap-ui-compatversion="edge"
      data-sap-ui-modules="demo/shared/onButtonPress"
      data-sap-ui-excludejquerycompat="true"
      data-sap-ui-resourceroots='{"demo": "./"}'
      data-sap-ui-xx-waitfortheme="init"
    ></script>
    <script>{
      sap.ui.getCore().attachInit(() => sap.ui.require([
        "sap/ui/core/mvc/XMLView",
      ], async XMLView => (await Promise.all([
        XMLView.create({ definition: defineView("First") }),
        XMLView.create({ definition: defineView("Second") }),
      ])).map(view => view.placeAt("content"))));

      function defineView(controllerName) {
        return `<mvc:View controllerName="demo.controller.${controllerName}"
          xmlns:mvc="sap.ui.core.mvc"
          xmlns="sap.m"
          xmlns:core="sap.ui.core"
          core:require="{ onButtonPress: 'demo/shared/onButtonPress' }">
          <Panel headerText="${controllerName} View">
            <Button text="Press" press="onButtonPress" />
          </Panel>
        </mvc:View>`;
      } // See OpenUI5 documentation topic "Handling Events in XML Views".
    }</script>
  </head>
  <body id="content" class="sapUiBody"></body>
</html>

sap.ui.define([
  "sap/m/MessageToast",
], function(MessageToast) {
  "use strict";

  return function(event) {
    const control = event.getSource();
    const message = `${control} pressed from ${this.getMetadata().getName()}`;
    MessageToast.show(message);
  };
});

sap.ui.define([
  "sap/ui/core/mvc/Controller",
], function(Controller) {
  "use strict";

  return Controller.extend("demo.controller.First", {
    // Nothing to see here.
    // Button press is handled in ./shared/eventHandler.js
  });
});

sap.ui.define([
  "sap/ui/core/mvc/Controller",
], function(Controller) {
  "use strict";

  return Controller.extend("demo.controller.Second", {
    // Nothing to see here.
    // Button press is handled in ./shared/eventHandler.js
  });
});