(3)-d. Apex Controller

With custom buttons, you can call the another methods that is defined in Apex Controller. 

You can also select the Apex Controller that is able to be called on the salesforce org connected (managed package is not available).  

※When you want to change Apex Controller to call the Apex Class, the code block below must be included in the Apex Class. 

  @AuraEnabled
  global static Object action(String data) {
    return SUPICE.SuPICE.action(data);
  }

【Customize Apex Controller】Not Checked 

【Customize Apex Controller】Checked 

The dialog below will pop up when you try to change the current Apex Controller to another one. 

The dialog will pop up when you try to click OK button in the advanced settings dialog without selecting any Apex Controller although Customize Apex Controller is checked.