el-select not showing selected label when v-model is manipulated in beforeMount() - vuejs2

el-select is not displaying the label of the selected option but is correctly updating the v-model with el-option :value. It is probably due to the manipulation in beforeMount() as when that is removed, the label correctly displays the option selected.
However, multiple object copies are required for my use case which is to map headers from uploaded files to expected headers where each file can have the same expected header.
Here's a fiddle with my issue: https://jsfiddle.net/c8auL7fk/

I submitted a bug report for this here: https://github.com/ElemeFE/element/issues/13373 and a contributor got back to me.
Vue is unable to catch changes to dynamically created properties. Objects need to be written in an immutable manner.
More details on immutable js objects here: https://wecodetheweb.com/2016/02/12/immutable-javascript-using-es6-and-beyond/

Related

VUE 3 JS Save value if object changes

I'm new to VUE but not to programming. The project is to convert an older server-built website to VUE and I'm looking to find the most efficient method to save data.
When a form (page) is loaded I pull the data from our server in a JSON object which is nicely converted to a JS object. Its big -- hundred or so properties.
I'm currently storing the object in a PINIA store as a reactive object, applying the object values directly to form inputs using v-model and everything works, is reactive, and once completed my object has all the necessary information to update (patch) the document.
What I'd like to do is send to the server JUSt the object that was changed and its new value.
For example: assume the object has many fields -- I'll just provide a few here
event:{user:'scott',pass:'12345',startDate:'11/01/2023',endDate:'11/01/2024'.....}
The page has tabs and in each tab we pull a subset of the complete object (fetched and stored).
Therefore, store.event object has one change -- startDate --
I'd like to build a function that watches the entire (100+ object), fire if any field has changed, then save it somewhere without an individual watch or computed property for each 100+ objects.
Suggestions?
I tried using watch with multiple elements -- it did fire but I was unable to determine which element (object) changed.
Watch(() => [store.event.contractdate,store.event.contractduedate],(cv,ov){.. do something}

Vue3 computed property in parent child component structure not working

After trying to find solution to this issue for hours on various forums i am posting this here.
So i have two components. 1) App and 2) Todo. Both renderes a list and i can complete items so there will be two lists one for incomplete items and one for complete items. you can click on item and it will be gone to complete items list.
So in my example you can see i am using same component but with two diffreent ways to give data to component. one using API and one using native js Data. in both cases it renderes but with api i can click on list item and it will be gone to completed list but with javascript array example it doesn't work. i am completely amazed with this because component is same. how it can affect like that.
many answer here do tell me that computed properties are not reactive as they are cached but what’s the solution to that ? i can put data variable but then the first case of api will not work because time it takes to fetch it. so please help me with this one.
complete code at sfc playground
You have reactivity issues the computed property probably expects that value to be constant because you provide a non-reactive array from the parent.
I think you have 2 options here:
you either provide a reactive prop from parent
or you set a local data attribute in the child-component so that vue will know that it can change
Your fiddle didn't work for me so I copied your code to codesandbox, I have both examples there but commented out the first solution, there you basically simply add the array to the data object and reference that in the code.
Second solution you can add a mounted hook to define reactiveAssignments to your data in the child component this way it will have the same reference so that's why it would work that way.
I think the first solution is simpler, but it is really up to which one you prefer.
You can check the solutions here in my codesanbox
A better approach could be though by setting up component events instead of v-models in the child you should use it in the parent because this way you are directly modifying the props. You can read more about this here: https://vuejs.org/guide/components/events.html#usage-with-v-model

Vue slot is not working in rare and unpredictable cases (potential vue bug?)

I have this weird bug with a slot that is unreliable in certain unknown cases.
Components
There are 3 hierarchical components.
The grandchild (headlessTable), which offers a slot named arrayValue.
The child (collapsableCard), which passes the slot between grandchild and parent.
The parent (orderDataCard), who decides to render a link for that slot.
Problem: Instead of rendering the link of the parent, the default slot html of the child is being rendered when new data is loaded.
Datastructure (orderDetails)
process (obj)
mark (string)
common (obj)
additionalArguments (array)
category (string)
type (string)
name (string)
value (string)
salesOrganisation (obj)
invoices (array)
invoiceAgreementId (string)
paymentType (string)
Reproduction
Stackblitz or Codesandbox
Please look at the field additionalArguments, it contains a link.
Press ALT+M to simulate fetching new data. Now, instead of rendering a link, the default slot html for that named slot is rendered instead.
You can press ALT+J to load the original data, but this time there's no link.
Initial data (ALT+J)
Loaded data (ALT+M)
Type
Equal value
mark
str
false
common
common
obj
true
salesOrganisation
salesOrganisation
obj
true
invoices (empty)
invoices
arr
false
How 2 resolve
if you uncomment line 68 in app.js (or line 73 in App.vue if you're on codesandbox), which is the field called mark
if invoices is not initially empty in app.js
if mark is removed from html in orderDataCard
if salesOrganisation is removed from html in orderDataCard
if the html in the v-for template section for invoiceItems is empty in orderDataCard
Obviously, these are not solutions.
Notes
In any case, there is no dependence or anything between any of the fields, so it's hard for me to understand why this happens and I suspect this to be a bug with vue. I already created an issue for this. However, devs won't look at the reproduction, because they think it's not minimal as #lines > 100. As soon as I delete any more meaningful lines, the bug is resolved and the removed code is not faulty, so it's very frustrating to work on this. I could still remove lines that are not meaningful, but that would make it more difficult for everyone involved to understand what data is being rendered.
Is anyone able to acknowledge the fact that this is a problem with vue and that the code is not reducible OR (I would prefer this) is anyone able to fix this?
The problem is linked to Vue handling of multiple instances of the same component. In OrderDataCard.vue you have two instances of Collapsable-Card without unique keys. In this case:
Vue uses an algorithm that minimizes element movement and tries to
patch/reuse elements of the same type in-place as much as possible.
I don't quite know how these algorithms work, and why, apparently, it reused the second instance (without a defined slot content), but, setting a unique key for these components solved the issue.
See the working code sandbox: https://codesandbox.io/s/admiring-hamilton-5ytpp?file=/src/components/OrderDataCard.vue:133-149.
Note: I couldn't trigger keyboard events in my browser, so I triggered them on button click.
This may not be the solution, but could help find it:
Objects
I noticed you are working with objects and turning them into arrays. Objects properties can be problematic to work with, because unlike arrays updated properties are not propagated. This is a problem with JavaScript, not Vue. Vue was only possible because of observers introduced, but objects are still not part of that.
You might run into problems when an object is partially updated.
I would suggest looking at Vue.set.
Old code of mine invokes it explicitly by window.Vue.set() for changes in object properties so Vue can propagate them correctly.
That is kind of a bug in Vue, but again stems from JavaScript itself.
Computed arrays
I'm not entirely sure but the computed arrays don't save the above issue with working with objects.
I would go the safe route and use Vue.set() when updating objects and object properties. You can still use the computed arrays then.
Otherwise the obvious: Make real arrays out of the objects instead of working with objects half the time.
this.process
Is there a good reason you are using this.process explicitly instead of the component's props? Or is that a component from a library?
Slots
Have you tried the exact same code but without using the collapsable-card? Just output the link itself? It might point to slot problems in the collapsable-card component. Maybe also partially because of the objects thing from above.

Initialize dynamic Component in Code using Vue.js

I am currently developing a web application that is used to display elements for events on a map provided by HERE Maps. I am using Vue.
I have some components, but the relevant component is the component HereMaps.vue which initializes the map using the HERE Maps Api.
The HERE Maps Api provides the possibility to place so called InfoBubbles on the map showing additional information. These InfoBubbles can be provided some HTML-code in order to customize their appearance.
Please refer to the documentation for additional information
Following the documentation the code looks something like this:
let bubble = new H.ui.InfoBubble(marker.getPosition(), {
content: "<div class='someClass'>Some Content</div>"
});
this.ui.addBubble(bubble)
This is happening after mount in the "mounted" method from Vue in the "HereMaps" component.
The Bubbles are added in a "closed" (hidden) form and dynamically "opened" to reveal their content when the corresponding marker icon on the map is clicked. Therefore the HTML-code is present on the DOM after the component is mounted and is not removed at a later stage.
Now instead of supplying custom code within each bubble added to the UI i want to just add a component like this:
let bubble = new H.ui.InfoBubble(marker.getPosition(), {
content: "<myDynamicComponent></myDynamicComponent>"
});
this.ui.addBubble(bubble)
It does not matter to me wether the component is initialized using props or if it is conditionally rendered depending on the state of a global variable. I just want to be able to use the "myDynamicComponent" in order to customize the appearance in a different file. Otherwise the design process gets very messy.
As far as i know this is not possible or at least i was not able to get it work. This is probably due to the fact that the "myDynamicComponent" is not used within the "template" of the "HereMaps" component und thus Vue does not know that it needs to render something here after the directive is added to the DOM in the "mounted" method.
This is what the InfoBubble looks using normal HTML as an argument:
This is what the InfoBubble looks using the component as an argument:
It appears to just be empty. No content of the "myDynamicComponent" is shown.
Does anyone have any idea how i could solve this problem.
Thank You.
Answer is a bit complicated and I bet you wouldn't like it:)
content param can accept String or Node value. So you can make new Vue with rendered your component and pass root element as content param.
BTW, Vue does not work as you think, <myDynamicComponent></myDynamicComponent> bindings, etc exists in HTML only in compile time. After that all custom elements(components) are compiled to render functions. So you can't use your components in that way.
Give us fiddle with your problem, so we can provide working example:)

Aurelia validation on dynamically created form

I was able to get Aurelia-validation working on a dynamically created form when using the compose element, but I've switched to custom elements for better encapsulation and reuse of the custom controls. However, now my validation seems to be half-broken.
https://gist.run/?id=6e97538c3888cae0f6134faed9d67362
Issue 1: The ValidateBindingBehavior is not doing anything. I suspect it's not finding the controller or matching the rules since the property name is not easily visible in the binding (due to dynamic controls).
Issue 2: For some reason validate() on submit actually only shows the first error instead of all of them. That indicates a problem but I don't know what.
Can anyone get the attached GistRun to work properly?