Strange problem with Vue component

I've tried writing a vue component while using Vue 3.4 and Inertiajs, but have run into a couple of odd issues.

The component is a lookup for contacts. As the user types, a list of matching contacts appears and if the user clicks on a name it's filled into the form. If no matching contact is found, a button appears to add a new contact. The button opens a modal dialog and after the form is completed, the input (and contact id) is updated.

Everything seemed to work ok, but issues appeared when I used the component a second time on the same parent form (for From and To). Here's what the "From" and "To" components look like on the parent form:

<ContactInput v-model:displayName = "display_name.from"
              v-model:form_contact_id = "entry_form.from_contact_id"
              v-model:form_contact_name = "entry_form.from_display_last_first"
              :id="'entry_from'" />


<ContactInput v-model:displayName = "display_name.to"
              v-model:form_contact_id = "entry_form.to_contact_id"
              v-model:form_contact_name = "entry_form.to_display_last_first"
              :id="'entry_to'" />

Here's how those are wired up in the component:

    const theDisplayName = defineModel( 'displayName' );
    const form_contact_id = defineModel( 'form_contact_id' );
    const form_contact_name = defineModel( 'form_contact_name' );

    const props = defineProps( ['id'] );

When a contact is selected or added, the id and name are passed to the parent form through 'form_contact_id' and 'form_contact_name'.

Everything works fine when the user selects a name from the list. It also works fine if the user adds a new contact on the From field.

But when the user adds a new contact on the second component (the 'To' field), two issues emerge.

First, after a successful response from the post to the server, things go wrong. The new contact is added to the database and the id is returned successfully, but instead of updating the 'To' fields in the parent form, the 'From' fields are updated and the new name appears in the first component. Also, the button on the To component is not removed, because the lookup.active variable is not being set to false, though the code sets it to false.

It seems as if, when the response returns from the post, the code in the first component (From) is being executed. I thought maybe it could be related to inertia, so I then tried using axios for the post but had the same result.

The second issue is, if a contact is added in the From field, then when a user tries to add a new contact in the To field, the modal contact form has not been cleared (though in the code it should be). It displays what was entered in the first component ('From' field). I've tried several ways to clear the form (and the vue devtools shows that the fields in the second component are empty), but the form on the screen still shows the earlier data.

Again, it seems as if it's showing the form of the first component (From), and the code in the second component (if it's being executed) does not have any effect on it.

To confuse things further, as a test, I created a new component 'ContactInput2' which is just a copy of the original and used that for the second component. But the same issues occurred. So the modal of one SFC is displaying data which was entered into a different SFC.

Why is this happening? Is there something else I should be doing to re-use the same component on a form? Thanks for any thoughts or suggestions you may have.

LaryAI

2 years ago

Level 58

It sounds like you're encountering issues with state management and prop handling in your Vue components. The problems you're describing suggest that there might be shared state or incorrect references between the two instances of your ContactInput component. Here's a step-by-step approach to troubleshoot and resolve the issues:

Ensure Unique Component Instances: Make sure that each instance of your ContactInput component has its own unique state. If you're using a shared object or variable for state, this could be causing the issue where one component's actions affect the other.
Properly Use v-model: Vue 3 uses a slightly different syntax for v-model with multiple bindings. You should bind each model separately. For example:

<ContactInput v-model:displayName="display_name.from" ... />
<ContactInput v-model:displayName="display_name.to" ... />

Scoped Modal State: Ensure that the modal state is scoped to each ContactInput instance. If the modal is a shared instance or if its state is not properly scoped, it could retain the state from previous interactions.
Watch for Prop Mutation: Avoid mutating props directly within a child component. Instead, emit an event to the parent component and let the parent handle the state change.
Use Keyed Components: If you're reusing the same component, consider using the key attribute to maintain the component's state separately.

Here's a revised version of your component setup that addresses some of these concerns:

<ContactInput
  v-model:displayName="display_name.from"
  v-model:contactId="entry_form.from_contact_id"
  v-model:contactName="entry_form.from_display_last_first"
  :key="'from'"
/>

<ContactInput
  v-model:displayName="display_name.to"
  v-model:contactId="entry_form.to_contact_id"
  v-model:contactName="entry_form.to_display_last_first"
  :key="'to'"
/>

And in your ContactInput component:

const emit = defineEmits(['update:displayName', 'update:contactId', 'update:contactName']);

function updateContact(contact) {
  emit('update:displayName', contact.displayName);
  emit('update:contactId', contact.id);
  emit('update:contactName', contact.name);
  // ... rest of your logic
}

Clear Modal Form: To clear the modal form, ensure that you're resetting the state within the ContactInput component and not relying on any external state.
Debugging: Use Vue Devtools to inspect the state of each component instance. Make sure that each ContactInput has its own separate state.
Component Isolation: If you're still facing issues, try to isolate the problem by creating a minimal reproduction of the issue with just the ContactInput component and its parent. This can help identify if the problem is within the component or due to interactions with other parts of your application.

If you've tried all of the above and the issue persists, please provide more code snippets from your ContactInput component, especially the parts handling the modal state and emitting events, so that we can further diagnose the problem.

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