A slot is a narrow notch or opening, such as a keyway in a lock or a hole for a coin in a machine. It can also refer to an allocated time period for an activity, as in a peak evening viewing slot.
A renderless component is one that doesn’t render any markup of its own, but passes data and functionality to other components that will then render the resulting HTML. A renderless component may define slots to pass information about its layout and content, which other components can then use as they wish.
In Vue, a slot can be either a default slot or a named slot. A default slot is defined with slot />, while a named slot is defined as slot name> />. A default slot can be assigned a fallback slot, which is rendered in case the child component doesn’t provide any custom content for the slot. Alternatively, the default slot can be marked as required, which prevents other components from using it without providing the required content. LOGIN GBOPLAY138
Named slots are used to define specific areas of a component that can be populated with different types of content. A slot can have a name, options, as, and generator_prop, which are used to describe the type of content that can be placed in a slot. Optionally, the slot can also be marked as required and can have a default value, which prevents other components from using it.
In this example, the Card component defines two slot name> />: a header slot and a footer slot. The header and footer slots can be filled with different types of content, which are then displayed in the corresponding places on the page. When the default slot is not provided, the parent component can use a v-for loop to iterate over the Slots in its children and render the resulting HTML.
Vue 3.3 introduced a new function called defineSlots() that allows a component to declare its slots and props in the script setup> block, making it fully type-safe. The function also provides a new v-slot directive that binds the slot name to its data property, which can be used in child components to render a slot’s contents.
In addition to supporting the slot> element, the new v-slot directive supports named slots, as well as a generator_prop for each of its slots. This provides a flexible way for developers to create reusable, encapsulated components with rich data and functionality. A named slot can be assigned a default value, or a generator_prop can be used to create a custom content object for a specific slot. This content object is then passed to the child component, which can then render it as its own output. This approach makes it easy for developers to write modular code and avoid duplicated elements on a page. This is especially helpful when dealing with large components that require a lot of content to work correctly. For example, a generic alert component might have several nested slot content objects to display different kinds of content, such as an inline message and an icon.