How set readOnly dynamically in record.js?

You should be able to adapt this Gist to do what you want:

Custom record view controller for setting entire record to read-only conditionally · GitHub

They key is to add the field name into the "noEditFields" array.

Thank you Angel Magana. This is work!

This is code to community

({
  /*  Author: Angel Magaña -- cheleguanaco@cheleguanaco.com
  *   File: ./custom/modules/Opportunities/clients/base/views/record/record.js
  * 
  * Set all fields to read-only conditionally
  */


  extendsFrom: 'RecordView',
  
  _renderHtml: function(){    
      var self = this;
      console.log("LOG: "+app.user.get('type'));
      if(app.user.get('type') != 'admin')  {
        self.noEditFields.push('my_custom_field');
      }
    
    this._super('_renderHtml');
    
  },  
  _dispose: function(){
    this._super('_dispose');
  }


})

Thank you Angel Magana. This is work!

This is code to community

({
  /*  Author: Angel Magaña -- cheleguanaco@cheleguanaco.com
  *   File: ./custom/modules/Opportunities/clients/base/views/record/record.js
  * 
  * Set all fields to read-only conditionally
  */


  extendsFrom: 'RecordView',
  
  _renderHtml: function(){    
      var self = this;
      console.log("LOG: "+app.user.get('type'));
      if(app.user.get('type') != 'admin')  {
        self.noEditFields.push('my_custom_field');
      }
    
    this._super('_renderHtml');
    
  },  
  _dispose: function(){
    this._super('_dispose');
  }


})