Hide subcategories without hiding their topics in topic list?

Support
6

In general, you should avoid full template overrides since they require maintenance - you have to run a diff and check what’s changed if a Discourse update breaks your theme.

What you can do, is take a step back and modify the data that gets passed to the template instead.

The topic-list-item is an ember component, so you can use api.modifyClass to make the changes you want

For example, here’s a snippet that will show the parent category badge in subcategory topics under the title. If the topic is in the main category, the code has no effect.

<script type="text/discourse-plugin" version="0.8">
  const { on } = require("discourse-common/utils/decorators");

  // parent category ids
  const targetCategoryIds = [9, 15, 50];

  const useParentCategory = function () {
    const parentCategory = this.attrs.topic.category.parentCategory;
    const switchToParent = parentCategory && targetCategoryIds.includes(parentCategory.id)

    if (switchToParent) {
      this.attrs.topic.set("category", parentCategory);
    }
  };

  api.modifyClass("component:topic-list-item", {
    @on("didReceiveAttrs")
    setCategory() {
      useParentCategory.call(this);
    }
  });

  api.modifyClass("component:latest-topic-list-item", {
    @on("didReceiveAttrs")
    setCategory() {
      useParentCategory.call(this);
    }
  });
</script>