I need to use computed property in my Category Layout page. When pages which are under this layout changed, computed must understand page changings. But I can't catch these changes and I can only catch changes if I use them in Watch property.
Layout.vue
v-app
v-main
nuxt
speed-dial-button(:page="page")
....
setup() {
const route = useRoute();
const page = ref('');
const currentPath = computed(()=>route.value.path);
if (['/eserler', '/en/artworks', '/ar/artworks'].includes(currentPath)) {
page.value = i18n.t('general.addNewArtwork');
} else if (['/kisiler', '/en/persons', '/ar/persons'].includes(currentPath)) {
page.value = i18n.t('general.addNewPerson');
} else if (['/etkinlikler', '/en/activities', '/ar/activities'].includes(currentPath)) {
page.value = i18n.t('general.addNewActivity');
}
console.log('page',page)
console.log('route',routePath)
return {
page,
};
}
This will work if I load page first time or if I leave layout and return again .
Your template will react, but not your log statement. Put that in a watcher. Set deep and immediate to your needs.
watch(route, value => {
// your code here
console.log(value.path)
}, {deep: true, immediate: true})
Related
How do you accomplish nested fetching in Nuxt 3?
I have two API's. The second API has to be triggered based on a value returned in the first API.
I tried the code snippet below, but it does not work, since page.Id is null at the time it is called. And I know that the first API return valid data. So I guess the second API is triggered before the result is back from the first API.
<script setup>
const route = useRoute()
const { data: page } = await useFetch(`/api/page/${route.params.slug}`)
const { data: paragraphs } = await useFetch(`/api/page/${page.Id}/paragraphs`)
</script>
Obviously this is a simple attempt, since there is no check if the first API actually return any data. And it is not even waiting for a response.
In Nuxt2 I would have placed the second API call inside .then() but with this new Composition API setup i'm a bit clueless.
You could watch the page then run the API call when the page is available, you should paragraphs as a ref then assign the destructed data to it :
<script setup>
const paragraphs = ref()
const route = useRoute()
const { data: page } = await useFetch(`/api/page/${route.params.slug}`)
watch(page, (newPage)=>{
if (newPage.Id) {
useFetch(`/api/page/${newPage.Id}/paragraphs`).then((response)=>{
paragraphs.value = response.data
})
}
}, {
deep: true,
immediate:true
})
</script>
One solution is to avoid using await. Also, use references to hold the values. This will allow your UI and other logic to be reactive.
<script setup>
const route = useRoute()
const page = ref()
const paragraphs = ref()
useFetch(`/api/page/${route.params.slug}`).then(it=> {
page.value = it
useFetch(`/api/page/${page.value.Id}/paragraphs`).then(it2=> {
paragraphs.value = it2
}
}
</script>
You can set your 2nd useFetch to not immediately execute until the first one has value:
<script setup>
const route = useRoute()
const { data: page } = await useFetch(`/api/page/${route.params.slug}`)
const { data: paragraphs } = await useFetch(`/api/page/${page.value?.Id}/paragraphs`, {
// prevent the request from firing immediately
immediate: false,
// watch reactive sources to auto-refresh
watch: [page]
})
</script>
You can also omit the watch option there and manually execute the 2nd useFetch.
But for it to get the updates, pass a function that returns a url instead:
const { data: page } = await useFetch(`/api/page/${route.params.slug}`)
const { data: paragraphs, execute } = await useFetch(() => `/api/page/${page.value?.Id}/paragraphs`, {
immediate: false,
})
watch(page, (val) => {
if (val.Id === 69) {
execute()
}
})
You should never call composables inside hooks.
More useFetch options can be seen here.
I pass data into a component via props:
<Comment :comment="currentCase.Comment" #comment="(c) => currentCase.Comment=c"></Comment>
currentCase is updated via a fetch call to an API during the setup of the component (the one that contains the line above)
The TS part of <Comment> is:
<script lang="ts" setup>
import { Comment } from 'components/helpers'
import { ref, watch } from 'vue'
const props = defineProps<{comment: Comment}>()
const emit = defineEmits(['comment'])
console.log(props)
const dateLastUpdated = ref<string>(props.comment?.DateLastUpdated as string)
const content = ref<string>(props.comment?.Content as string)
watch(content, () => emit('comment', {DateLastUpdated: dateLastUpdated, Content: content}))
</script>
... where Comment is defined in 'components/helpers' as
export class Comment {
DateLastUpdated?: string
Content?: string
public constructor(init?: Partial<Case>) {
Object.assign(this, init)
}
}
content is used in the template, but is empty when the component is rendered. I added a console.log() to check whether the props were known - and what is passed is undefined at that point:
▸ Proxy {comment: undefined}
When looking at the value of the props once the application is rendered, their content is correct:
{
"comment": {
"DateLastUpdated": "",
"Content": "comment 2 here"
}
}
My question: why is comment not updated when props are available (and when are their content available?)
I also tried to push the update later in the reactive cycle, but the result is the same:
const dateLastUpdated = ref<string>('')
const content = ref<string>('')
onMounted(() => {
console.log(props)
dateLastUpdated.value = props.comment?.DateLastUpdated as string
content.value = props.comment?.Content as string
watch(content, () => emit('comment', {DateLastUpdated: dateLastUpdated, Content: content}))
})
Vue lifecycle creates component instances from parent to child, then mounts them in the opposite order. Prop value is expected to be available in a child if it's available at this time in a parent. If currentCase is set asynchronously in a parent, the value it's set to isn't available on component creation, it's a mistake to access it early.
This disables the reactivity:
content.value = props.comment?.Content as string
props.comment?.Content === undefined at the time when this code is evaluated, it's the same as writing:
content.value = undefined;
Even if it weren't undefined, content wouldn't react to comment changes any way, unless props.comment is explicitly watched.
If content is supposed to always react to props.comment changes, it should be computed ref instead:
const content = computed(() => props.comment?.Content as string);
Otherwise it should be a ref and a watcher:
const content = ref();
const unwatch = watchEffect(() => {
if (props.comment?.Content) {
content.value = props.comment.Content;
unwatch();
...
}
});
I have a problem using Quasar with VueJs.
When I use Quasar's Loading.show() method, the scroll is stuck when I go to the new page, and the top of the new page is not shown.
In the router/index.js file i have set
const router = new VueRouter({
scrollBehavior: () => ({ x: 0, y: 0}),
...
});
For example:
In MainLayout.vue (which is the parent component of the index and category page), I have set a watch to show the loading screen when the isLoading flag is true in the state.
watch: {
isLoading: {
deep: true,
handler(isLoading) {
if(isLoading == true) {
Loading.show();
} else {
Loading.hide();
}
}
}
}
This is working fine, but when I have clicked a link to a category page after I have scrolled a little bit, The category page will also retain the previous scroll position.
Is working without the scroll issue with commented out Loading.show();
Video from the issue:
https://drive.google.com/file/d/1d-WaxHazNdZ8bp3_pcN14hcayucUYYUb/view
Try to do this, but I'm not sure if this is the right solution:
import { scroll } from 'quasar'
const { getScrollTarget, setVerticalScrollPosition } = scroll
watch: {
isLoading: {
deep: true,
handler(isLoading) {
if(isLoading == true) {
Loading.show();
} else {
Loading.hide();
const el = document.querySelector('.q-page-container')
const target = getScrollTarget(el)
const offset = el.offsetTop
const duration = 0
setTimeout(() => setVerticalScrollPosition(target, offset, duration), 400);
}
}
}
}
Documentation https://quasar.dev/quasar-utils/scrolling-utils#scrolling-to-an-element
I have a Vue.js SPA with some pages that display data from a backend. When I navigate the pages via the navbar, everything works fine, components and data are loaded.
When I'm on the page, e.g. localhost:8080/#/mypage and press F5, the data doesn't get loaded / rendered. Same goes for when I directly navigate to the page via the address bar.
The data gets loaded in this function:
async beforeMount() {
await this.initializeData();
}
I've tried to call the method in every lifecycle hook, i.e. created, beforeCreated, mounted etc...
In the mounted lifecycle hook I'm setting a boolean property to true, so that the table is only rendered when the component is loaded (done with v-if).
mounted() {
this.componentLoaded = true;
}
Not sure if this is important, but I've tried it with or without and it doesn't work.
I would really appreciate it if somebody knew whats happening here.
EDIT:
this.applications is a prop and contains multiple applications which contain instances. I want to add some variables from the backend to each application.
console.log(1) gets printed
console.log(2) does not
initializeData: function () {
let warn = 0;
console.log("1");
this.applications.forEach(async application => {
const instance = application.instances[0];
console.log("2");
let myData = null;
try {
const response = await instance.axios.get('url/myData');
myData = response.data;
} catch (err) {
}
let tmpCount = 0;
let tmpFulfilled = 0;
myData.forEach(ba => {
if(!ba.fulfilled){
warn++;
application.baAllFulfilled = false;
}else {
tmpFulfilled++;
}
tmpCount++;
})
console.log("3");
// Assign values
this.baTotalWarnings = warn;
application.baAnzahl = tmpCount;
application.baFulfilled = tmpFulfilled;
this.componentLoaded = true;
}
Try removing the async and await keywords from your beforeMount, and remove this.componentLoaded from mounted. Set it instead in the then block (or after await) in your initializeData method. I'm not sure Vue supports the async keyword in its lifecycle methods.
Something like this:
beforeMount() {
this.initializeData(); // start processing the method
}
methods: {
initializeData() {
callToBackend().then(() => {
this.componentLoaded = true // backend call ready, can now show the table
})
}
}
I have a basic VueJS application with only one page.
It's not a SPA, and I do not use vue-router.
I would like to implement a button that when clicked executes the window.open() function with content from one of my Vue Components.
Looking at the documentation from window.open() I saw the following statement for URL:
URL accepts a path or URL to an HTML page, image file, or any other resource which is supported by the browser.
Is it possible to pass a component as an argument for window.open()?
I was able to use some insights from an article about Portals in React to create a Vue component which is able to mount its children in a new window, while preserving reactivity! It's as simple as:
<window-portal>
I appear in a new window!
</window-portal>
Try it in this codesandbox!
The code for this component is as follows:
<template>
<div v-if="open">
<slot />
</div>
</template>
<script>
export default {
name: 'window-portal',
props: {
open: {
type: Boolean,
default: false,
}
},
data() {
return {
windowRef: null,
}
},
watch: {
open(newOpen) {
if(newOpen) {
this.openPortal();
} else {
this.closePortal();
}
}
},
methods: {
openPortal() {
this.windowRef = window.open("", "", "width=600,height=400,left=200,top=200");
this.windowRef.addEventListener('beforeunload', this.closePortal);
// magic!
this.windowRef.document.body.appendChild(this.$el);
},
closePortal() {
if(this.windowRef) {
this.windowRef.close();
this.windowRef = null;
this.$emit('close');
}
}
},
mounted() {
if(this.open) {
this.openPortal();
}
},
beforeDestroy() {
if (this.windowRef) {
this.closePortal();
}
}
}
</script>
The key is the line this.windowRef.document.body.appendChild(this.$el); this line effectively removes the DOM element associated with the Vue component (the top-level <div>) from the parent window and inserts it into the body of the child window. Since this element is the same reference as the one Vue would normally update, just in a different place, everything Just Works - Vue continues to update the element in response to databinding changes, despite it being mounted in a new window. I was actually quite surprised at how simple this was!
You cannot pass a Vue component, because window.open doesn't know about Vue. What you can do, however, is to create a route which displays your component and pass this route's URL to window.open, giving you a new window with your component. Communication between the components in different windows might get tricky though.
For example, if your main vue is declared like so
var app = new Vue({...});
If you only need to render a few pieces of data in the new window, you could just reference the data model from the parent window.
var app1 = window.opener.app;
var title = app.title;
var h1 = document.createElement("H1");
h1.innerHTML = title;
document.body.appendChild(h1);
I ported the Alex contribution to Composition API and works pretty well.
The only annoyance is that the created window ignores size and position, maybe because it is launched from a Chrome application that is fullscreen. Any idea?
<script setup lang="ts">
import {ref, onMounted, onBeforeUnmount, watch, nextTick} from "vue";
const props = defineProps<{modelValue: boolean;}>();
const emit = defineEmits(["update:modelValue"]);
let windowRef: Window | null = null;
const portal = ref(null);
const copyStyles = (sourceDoc: Document, targetDoc: Document): void => {
// eslint-disable-next-line unicorn/prefer-spread
for(const styleSheet of Array.from(sourceDoc.styleSheets)) {
if(styleSheet.cssRules) {
// for <style> elements
const nwStyleElement = sourceDoc.createElement("style");
// eslint-disable-next-line unicorn/prefer-spread
for(const cssRule of Array.from(styleSheet.cssRules)) {
// write the text of each rule into the body of the style element
nwStyleElement.append(sourceDoc.createTextNode(cssRule.cssText));
}
targetDoc.head.append(nwStyleElement);
}
else if(styleSheet.href) {
// for <link> elements loading CSS from a URL
const nwLinkElement = sourceDoc.createElement("link");
nwLinkElement.rel = "stylesheet";
nwLinkElement.href = styleSheet.href;
targetDoc.head.append(nwLinkElement);
}
}
};
const openPortal = (): void => {
nextTick().then((): void => {
windowRef = window.open("", "", "width=600,height=400,left=200,top=200");
if(!windowRef || !portal.value) return;
windowRef.document.body.append(portal.value);
copyStyles(window.document, windowRef.document);
windowRef.addEventListener("beforeunload", closePortal);
})
.catch((error: Error) => console.error("Cannot instantiate portal", error.message));
};
const closePortal = (): void => {
if(windowRef) {
windowRef.close();
windowRef = null;
emit("update:modelValue", false);
}
};
watch(props, () => {
if(props.modelValue) {
openPortal();
}
else {
closePortal();
}
});
onMounted(() => {
if(props.modelValue) {
openPortal();
}
});
onBeforeUnmount(() => {
if(windowRef) {
closePortal();
}
});
</script>
<template>
<div v-if="props.modelValue" ref="portal">
<slot />
</div>
</template>