Slots Vs Props Vue
I found a way to get access tot the scoped slot props outside of the slot but it’s a hack. Make a component to just receive a prop( the scoped slot provided prop). And do with it whatever you want. But there has to be a better way. A slot allows you to display an element in the child that is controlled by the parent. This helps make your components reusable. For example, let’s say you have a child component that displays data as a line chart, with the prop:chartData=“chartData”. While basic component slots are all fine and dandy, sometimes you want the template inside the slot to be able to access data from the child component hosting the slot content. For example, if you’re trying to allow custom templates in a container while still retaining access to those containers’ data properties, you’ll want to use a. The child component contains a prop called 'signal'. I would like to be able to change data called 'parentVal' in the parent component so that the children's signal prop is updated with the parent's value. This seems like it should be something simple, but I cannot figure out how to do this using slots: Here is a running example below. A prop to toggle bold/italics. A prop to decide on the max length of the option label before adding an ellipsis. A prop to use as a key to select a value out an object, if the select can be passed an array of objects to list. A prop to apply a prefix or suffix to option labels. And now you have a select with 50 props.
This page assumes you’ve already read the Components Basics. Read that first if you are new to components.
Slot Content
Vue implements a content distribution API that’s modeled after the current Web Components spec draft, using the <slot> element to serve as distribution outlets for content.
This allows you to compose components like this:
Then in the template for <navigation-link>, you might have:
When the component renders, the <slot> element will be replaced by “Your Profile”. Slots can contain any template code, including HTML:
Or even other components:
If <navigation-link> did not contain a <slot> element, any content passed to it would simply be discarded.
Named Slots
There are times when it’s useful to have multiple slots. For example, in a hypothetical base-layout component with the following template:
For these cases, the <slot> element has a special attribute, name, which can be used to define additional slots:
To provide content to named slots, we can use the slot attribute on a <template> element in the parent:
Or, the slot attribute can also be used directly on a normal element:
There can still be one unnamed slot, which is the default slot that serves as a catch-all outlet for any unmatched content. In both examples above, the rendered HTML would be:
Default Slot Content
There are cases when it’s useful to provide a slot with default content. For example, a <submit-button> component might want the content of the button to be “Submit” by default, but also allow users to override with “Save”, “Upload”, or anything else.
To achieve this, specify the default content in between the <slot> tags.
If the slot is provided content by the parent, it will replace the default content.
Compilation Scope
When you want to use data inside a slot, such as in:
That slot has access to the same instance properties (i.e. the same “scope”) as the rest of the template. The slot does not have access to <navigation-link>‘s scope. For example, trying to access url would not work. As a rule, remember that:
Everything in the parent template is compiled in parent scope; everything in the child template is compiled in the child scope.
Scoped Slots
New in 2.1.0+
Sometimes you’ll want to provide a component with a reusable slot that can access data from the child component. For example, a simple <todo-list> component may contain the following in its template:
But in some parts of our app, we want the individual todo items to render something different than just the todo.text. This is where scoped slots come in.
To make the feature possible, all we have to do is wrap the todo item content in a <slot> element, then pass the slot any data relevant to its context: in this case, the todo object:
Now when we use the <todo-list> component, we can optionally define an alternative <template> for todo items, but with access to data from the child via the slot-scope attribute:
In 2.5.0+, slot-scope is no longer limited to the <template> element, but can instead be used on any element or component in the slot.
Destructuring slot-scope
The value of slot-scope can actually accept any valid JavaScript expression that can appear in the argument position of a function definition. This means in supported environments (single-file components or modern browsers) you can also use ES2015 destructuring in the expression, like so:
This is a great way to make scoped slots a little cleaner.
