@鲍永道
是继承的字段selection,我只需要显示即只读状态下显示背景颜色。如下:
(不知道是否还有更好的解决方法)
ps:用原版的css样式,颜色太淡了,不满足需要的可以考虑写css。
odoo.define('product.modify_field_value_bgcolor', function (require) {
    "use strict";
    var relational_fields = require('web.relational_fields');
    var FieldSelection = relational_fields.FieldSelection;
    FieldSelection.include({
        /**
         * @override
         * @private
         */
        _renderReadonly: function () {
            var formatValue = this._formatValue(this.value);
            if(formatValue === 'In Process'){
                this.$el.addClass('bg-warning');
            }else if(formatValue === 'Ready'){
                this.$el.addClass('bg-primary');
            }else if(formatValue === 'Complete'){
                this.$el.addClass('bg-success');
            }else if(formatValue === 'Problem'){
                this.$el.addClass('bg-danger');
            }
            this.$el.empty().text(formatValue);
        },
    });
});