I try to learn how i can create custom element for Shopware 6
although I cannot understand why we have to use the methods:
this.$emit('element-update', this.element);
in all SW Blocks?
All CMS element components should use the cms-element mixin. The mixin has a model for the property element which is bound to the element-update event. By emitting this event with the value you update the property, as if you were using a child component with the form input binding v-model. Since mutating props directly is considered an anti-pattern, this is a way to properly update it.
Related
According to Vue.js docs (Components: One-Way data Flow) I assumed that I'm not able to update parent's variable from child component.
How is it possible, that when I bind a variable to child component, it is updated without emitting any event?
Here is Vue SFC playground example.
How can I use a copy of variable in child component without propagating changes to parent?
Edit: I'm curious why the property userAccount in AccountPage.vue gets updated.
There's no v-model, no events submitted, yet it still gets updated.
Edit:
In AccountForm.Vue an reactive and mutable ref object is created when writing
const userAccount = ref ({..})
Changing the reactive object will affect the parent. If you remove the ref() you'll see that the parent isn't updated.
https://v3.vuejs.org/api/refs-api.html#ref
Old answer:
When you use v-model you create a two-way data binding. V-model is a shorthand for v-bind and input, that is you bind data to child via v-bind and receive data via input event that is emitted from child.
So,
<input v-model="searchText">
is the same as writing
<input
v-bind:value="searchText"
v-on:input="searchText = $event.target.value"
>
https://v2.vuejs.org/v2/guide/components.html#Using-v-model-on-Components
The example demonstrates the usage of v-model and as stated in the docs
Custom events can also be used to create custom inputs that work with
v-model. Remember that:
<input v-model="searchText">
does the same thing as:
<input v-bind:value="searchText" v-on:input="searchText = $event.target.value">
meaning it does fire an event
This question already has answers here:
Pass data to a directive?
(2 answers)
Closed 1 year ago.
I am creating a component system that will let other developers write vue applications with the components to quickly get up and running with simple forms.
My components are very general, and expect plain values to be bound to their value property, and will emit plain values with their input events.
The data we want the components to control is complex. I've read that you cannot use classes as vue data, because vue expects plain javascript objects for data. So each piece of data is an object like
{
_value: ...
setVal(): ...
getVal(): ...
}
And we are binding like
<my-component
:value="dataObject.getVal()"
#input="dataObject.setVal($event)"
/>
I thought it might be possible to write a vue directive to shorthand those properties, like how v-model is a shorthand for :value and #input normally, so that I could write
<my-component v-my-directive="dataObject" />
and it automatically binds the right thing to :value and the right thing to #input, but it doesn't seem to be that simple. I've found tutorials that mention twoway for Vue v1 directives, but that was removed in Vue v2, which recommended using a wrapper component as a replacement. But we have a large library of components, writing and maintaining a wrapper for each one seems out of line for just creating a shorthand like what already exists. Is there any other way?
vue2 only allows v-model directive to be bound to :value/#input. So you need to use both v-bind and #on directives for 2 way binding.
vue3 combines these using a convention that allows for multiple v-model bindings
You create a prop called 'foo' and emit and event called 'update:foo' with the value you want to assign to it.
The parent component uses v-model:foo to bind to it.
From Vue documentation:
All props form a one-way-down binding between the child property and the parent one: when the parent property updates, it will flow down to the child, but not the other way around.
However, if to pass the nested object or array from parent's data as child component's parameter and child will change it, the data of parent will change, too.
Ideally, good framework must take care about deep copying when required, but Vue does not.
The one of solution is creating the copy based on parameter's value. Should I do it?
I dont think creating copy is a good solution as far as i know.
The best practice for your task is to use .sync modifier!
I am using Inertiajs
with Laravel and also trying to use Element UI components but as i use Menu component i am having following error in console, I just used example as given in Element Ui Components as i was testing.
I see 2 different errors in there, both of them are with props.
I assume your component is taking the route as a prop, and you are also using the route as a method, which you might have put inside methods: {} which is not allowed. Make sure you rename your method route to something else.
Note: As a matter of fact you can't have any data coinciding with each other. your props, data, computed props and methods all should have unique names.
You are trying to use v-model on the props directly which won't work in Vue. if the prop is a primitive (Number, String, Boolean etc). but you can pass Object or an Array which can hold a reference to the data. This is because reactivity in Vue can't keep track of props when passed as primitives.
More on prop mutations here: https://v2.vuejs.org/v2/guide/components-props.html#One-Way-Data-Flow
I am new in VUE.JS but i have finished some beginner courses of vuemastery. Though I know how to bind properties and how to emit custom events, I have a problem: I don't know how to make these things through multiple levels of components.
Let's say we have the following hierarchy:
I need to have control on the Home component's properties from the Elements and Input components from the bottom of the diagram. Right now I am emitting custom events from level to level from down to up, but it doesn't look like an elegant solution.
Is there a better way to do this? And of course when I change one of the properties from Input component it need to have effect on the properties in the Element components as well.
For example the Element components are elements having width and height calculated based on totalWidth property, which can be edited in the Input component. I'm having here a warn as well in the console: [Vue warn]: Avoid mutating a prop directly since the value will be overwritten whenever the parent component re-renders.
Use this.$root.$emit to emit event on the root component, that would then propagate event on its child components, regardless of depth level
I would recommend using vuex to manage the state of your application. Emitting events all over the place is not the most elegant solution.