I'm coding an app for managing shift work. The idea is pretty simple: the team is shared between groups. In those groups are specific shifts. I want to get something like that:
Group 1
- shift11
- shift12
- shift13
Group 2
- shift21
- shift22
- shift23
I already made a couple of tests, but nothing is really working as I would like it to: everything reactive, and dynamic.
I'm using vue.js, firestore (and vuefire between them).
I created a collection "shiftGroup" with documents (with auto IDs) having fields "name" and "order" (to rearrange the display order) and another collection "shift" with documents (still auto IDs) having fields "name", "order" (again to rearrange the display order, inside the group) and "group" (the ID of the corresponding shiftGroup.)
I had also tried with firestore.References of shifts in groups, that's when I was the closest to my goal, but then I was stuck when trying to sort shifts inside groups.
Anyway, with vuefire, I can easily bind shiftGroup like this:
{
data () {
return {
shiftGroup: [], // to initialize
}
},
firestore () {
return {
shiftGroup: db.collection('shiftGroup').orderBy('order'),
}
},
}
Then display the groups like this:
<ul>
<li v-for="(group, idx) in shiftGroup" :key="idx">{{group.name}}</li>
</ul>
So now time to add the shifts...
I thought I could get a reactive array of shifts for each of the groups, like that:
{
db.collection('shift').where('group', '==', group.id).orderBy('order').onSnapshot((querySnapshot) => {
this.shiftCollections[group.id] = [];
querySnapshot.forEach((doc) => {
this.shiftCollections[group.id].push(doc.data());
});
});
}
then I'd call the proper list like this:
<ul>
<li v-for="(group, idx) in shiftGroup" :key="idx">
{{group.name}}
<ul>
<li v-for="(shift, idx2) in shiftCollections[group.id]" :key="idx1+idx2">{{shift.name}}</li>
</ul>
</li>
</ul>
This is very bad code, and actually, the more I think about it, the more I think that it's just impossible to achieve.
Of course I thought of using programmatic binding like explained in the official doc:
this.$bind('documents', documents.where('creator', '==', this.id)).then(
But the first argument has to be a string whereas I need to work with dynamic data.
If anyone could suggest me a way to obtain what I described.
Thank you all very much
So I realize this is an old question, but it was in important use case for an app I am working on as well. That is, I would like to have an object with an arbitrary number of keys, each of which is bound to a Firestore document.
The solution I came up with is based off looking at the walkGet code in shared.ts. Basically, you use . notation when calling $bind. Each dot will reference a nested property. For example, binding to docs.123 will bind to docs['123']. So something along the lines of the following should work
export default {
name: "component",
data: function () {
return {
docs: {},
indices: [],
}
},
watch: {
indices: function (value) {
value.forEach(idx => this.$bind(`docs.${idx}`, db.doc(idx)))
}
}
}
In this example, the docs object has keys bound to Firestore documents and the reactivity works.
One issue that I'm trying to work through is whether you can also watch indices to get updates if any of the documents changes. Right now, I've observed that changes to the Firestore documents won't trigger a call to any watchers of indices. I presume this is related to Vue's reactivity, but I'm not sure.
Related
I'm attempting to set data fields provided by an array based on the Vue Router query. For example, when someone lands on my website using example.com/?location=texas, I want to set the location data by an array.
An example the array:
locations {
{
slug: "texas",
tagline: "Welcome to Texas",
}, {
slug: "california",
tagline: "Welcome to California",
}
}
I know this should be done using a computed property, however I am unable to get anything functioning. I've tried simple tests like if (this.slug.location === "texas"), and I cannot get the location data to populate. I would also like to provide default data in case there are no route matches.
Any help is extremely appreciated!
Edit:
I can accomplish this in a very manual way. Right now, I'm setting the query in data by the following:
slug: this.$route.query.location
I can display specific text by doing something like:
h3(v-if="slug === 'texas'") This will show for texas
h3(v-else-if="slug === 'california'") This will show for California
h3(v-else) This is default
The issue with this approach is there are various elements I need to customize depending on the slug. Is there any way I can create an array, and move whichever array matches a key in an array to the data??
You should be able to access a query param using the following (link to Vue Router documentation):
this.$route.query.location
So based on what you listed I would do something like...
export default {
computed: {
displayBasedOnLocationQueryParam() {
switch(this.$route.query.location) {
case 'texas':
return 'Welcome to Texas'
default:
return 'hello there, generic person'
}
}
}
}
Note that I'm not using your array explicitly there. The switch statement can be the sole source of that logic, if need be.
Using a v-for loop in Vue js. I am looping through the readingTasks data object which correctly produces two results from the data below.
readingTasks:Array[2]
0:Object
enabled:true
newunit:-1
task:"The part 3 guide"
unit:-1
unit_task_id:27
url:"#"
1:Object
enabled:true
newunit:-1
task:"The part 3 training units"
unit:-1
unit_task_id:28
url:"#"
The bit I am unsure about is how for each result, how do I run another Axios database call that shows if the reading Task is complete or not. For example for the first record, the complete status should be true (unit_task_id:27) and the second record should be false.
userTasks:Array[1]
0:Object
complete:true
enabled:true
newunit:-1
task:"The part 3 guide"
unit:-1
unit_task_id:27
unit_task_user_id:21
<ul>
<li v-for="task in readingTasks">
{{task.task}}
//trying to call a function that does an Axios call passing in parameters from readingTasks
{{getUserTaskByUnit(task.unit, task.unit_task_id)}}
<template v-for="usertask in userTasks">
{{usertask.complete}}
</template>
</li>
</ul>
//javascript if its useful
data: {
readingTasks: [],
userTasks: []
},
mounted() {
this.lastUnit();
},
methods: {
//functons
lastUnit: function() {
this.tasks();
},
tasks: function() {
var self = this;
var unit = this.unit;
axios.get("/WebService/units.asmx/GetTasks?unit=" + unit).then(function(response) {
self.readingTasks = response.data;
})
.catch(function(error) {
console.log(error);
})
.then(function() {
});
},
getUserTaskByUnit: function(unit, unitTaskId) {
var self = this;
axios.get("/WebService/units.asmx/GetUserTasks?unit=" + unit + "&unitTaskId=" + unitTaskId).then(function(response) {
self.userTasks = response.data;
})
.catch(function(error) {
console.log(error);
})
.then(function() {});
}
This code seems close to doing the correct thing, however {{usertask.complete}} flickers between true and false for both sets of results. Like it is stuck in a loop.
I would expect the first result to show True here and the second result to show False.
The part 3 guide - true
The part 3 training units - false
There are a few problems here.
The template has a dependency on userTasks, so every time userTasks changes it will cause the component to re-render, running the template again.
Every time the template runs it calls getUserTaskByUnit for both tasks. That will, asynchronously, update userTasks. When userTasks is updated it will trigger a re-render, which will call getUserTaskByUnit again, going round and round in an infinite loop.
Worse than just being an infinite loop, each time it renders it will trigger two requests, each of which will trigger another re-rendering. The number of requests will balloon exponentially.
When those requests do return you're then storing them in userTasks. But both responses are being stored in exactly the same place, so you'll only ever see the results of one request in the UI.
The first thing you'll need is a better data structure for storing the responses in getUserTaskByUnit. The simplest place to store them would be on the tasks in readingTask. That might look something like this:
// Note the whole task is now being passed to getUserTaskByUnit
getUserTaskByUnit: function(task) {
var self = this;
axios.get("/WebService/units.asmx/GetUserTasks?unit=" + task.unit + "&unitTaskId=" + task.unit_task_id).then(function(response) {
task.userTasks = response.data;
})
...
}
The call to getUserTaskByUnit needs moving out of the template. Moving it into the tasks method seems as good a place as any. There are also a few changes required to get it to work with the new version of getUserTaskByUnit:
tasks: function() {
var self = this;
var unit = this.unit;
axios.get("/WebService/units.asmx/GetTasks?unit=" + unit).then(function(response) {
var readingTasks = response.data;
// Pre-populate userTasks so it will be reactive
readingTasks.forEach(function(task) {
task.userTasks = [];
});
// This must come after userTasks is pre-populated
self.readingTasks = readingTasks;
readingTasks.forEach(function(task) {
// Passing task to getUserTaskByUnit, not unit and unit_task_id
self.getUserTaskByUnit(task);
});
})
...
Then within the template we'd need to loop over task.userTasks:
<ul>
<li v-for="task in readingTasks">
{{task.task}}
<template v-for="usertask in task.userTasks">
{{usertask.complete}}
</template>
</li>
</ul>
There are alternative data structures we could use depending on what other requirements you have. For example, you could retain a separate userTasks object to hold the userTasks but for that to work it would need to be a nested data structure rather than just an array. You'd need to key it by unit and then unitTaskId. The result in the template would be something like this:
<ul>
<li v-for="task in readingTasks">
{{task.task}}
<template v-for="usertask in userTasks[task.unit][task.unit_task_id]">
{{usertask.complete}}
</template>
</li>
</ul>
Much like with the earlier solution you would need to pre-populate the userTasks with empty values when readingTasks first loads to ensure the values are reactive and also to avoid the template blowing up at the undefined entries. Alternatively you could use $set and suitable v-if checks respectively.
This is all quite fiddly. It may be that you can simplify it a little based on your knowledge of the system. For example, it may be possible to form compound string keys for userTasks rather than using two levels of nesting. Or it might be that unit is a prop that can be considered constant and doesn't need including in that data structure.
Your userTasks is a view property and gets overwritten upon every call to getUserTaskByUnit (i.e. for each item in readingTasks). What you instead want is a nested structure. You should call getUserTaskByUnit in a loop as soon as readingTasks got loaded, i.e. after the line self.readingTasks = response.data;, and store the response as a property for every readingTask object.
I'm trying to get my head around how to best implement the following requirements into a Vuex (vue.js) application.
I'll try and keep it as simple as possible, what i'm looking to achieve is something similar to Hacker News site. Therefore application will need to calculate a score for each item (post) based on a calculation/algorithm. The score is determined by a combination of likes and the date it was created on. Therefore the scores are constantly updating (until a designated time period expires) therefore it the score is not stored in a data source but calculated by the app.
So my main question is, how best to go about implementing this for a Vuex application?
I have set up a Vuex store of posts (i've called each article a 'post') and I'm able to display all the posts in a list. So now i've have two main objectives:
Assign a score to the posts (articles)
Filter the posts results list by their scores.
I've done some research and the consensus feels like it would be best to keep the 'score' separate from the 'posts' store (not added to the 'posts' array).
The following code works fine, however feels verbose. Would it be better to move any of these functions to 'getters/mutations/actions'?
Please note: for this examples i've simplified the calculation/algorithm to 'likes' total plus 'comments' total, obviously the final algorithm is more complicated to work like hacker news.
<div>
<button #click="postFilterKey = 'all'"><button>
<button #click="postFilterKey = 'orderByScore'"><button>
</div>
<div v-for="post in filterPosts" v-bind:key="post.value">
<p>Title: {{ post.title }}</p>
<p>Total Likes: {{ post.likes }}</p>
<p>Total Comments: {{ post.comments }}</p>
<p>Score: {{ post.comments | getScore(post.likes) }}</p>
</div>
computed: {
...mapState(["posts"]),
filterPosts () {
return this[this.postFilterKey]
},
all () {
return this.posts;
},
orderByScore (){
return this.posts.sort((b,a) =>
this.calculateScore(a.totalComments, a.totalLike) -
this.calculateScore(b.totalComments, b.totalLike));
},
methods: {
calculateScore(totalComments, totalLikes) {
let score = totalComments + totalLikes
return score;
},
}
filters: {
getScore(totalComments, totalLikes) {
let score = totalComments + totalLikes
return score;
},
}
Thanks for having a look.
Like you said, what you have will work fine, and there is nothing wrong with it, per se.
There are a couple issues with your current code that could be improved:
If you want to reuse the score anywhere else in your app that is not a direct child of this component, you will have to duplicate the getScore() function in that component which is harder to maintain.
Every time the page is rendered the getScore() function gets re-run once for every post in the list, and every time the user sorts the list, the calculateScore() and getScore() functions will re-run once for each item in the list, which is not very efficient.
One solution, as you alluded to, is to put these functions in the store as getters. This would solve both issues I listed above by:
Keeping your code DRY by keeping these functions in one location.
Running these functions as vuex getters will cache the results so that they only re-run if the state they are dependent on changes.
An example of what your getter property in your store may look like is:
getters: {
postsWithScore: state => {
return state.posts.map(post => {
return {
...post,
score: post.comments + post.likes,
});
}
}
See the vuex docs for more info: https://vuex.vuejs.org/guide/getters.html
I would consider moving the score calculation to a getter. It feels like a piece of the business model, why should it be fixed in a component that's merely using it? From what I recall, vuex's getter have some caching built in, so there's performance gain as well.
PS. Dynamic scoring base on time has its downsides btw. You probably don't wanna move the items around while user looks at them, but what about pagination? When user goes to the next page and your score changes in the meantime, then the continuity of the list is broke. Anyhow, it's just kinda UX concern I believe.
Vue is not registering event handler for HTML injected objects. How do I do this manually or what is a better way to work around my problem?
Specifically, I send a query to my server to find a token in text and return the context (surrounding text) of that token as it exists in unstructured natural language. The server also goes through the context and finds a list of those words that also happen to be in my token set.
When I render to my page I want all of these found tokens in the list to be clickable so that I can send the text of that token as a new search query. The big problem I am having is my issue does not conform to a template. The clickable text varies in number and positioning.
An example of what I am talking about is that my return may look like:
{
"context": "When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected",
"chunks": ['human events', 'one people', 'political bands']
}
And the resulting output I am looking for is the sentence looks something like this in psuedocode:
When in the Course of <a #click='search("human events")'>human events</a>, it becomes necessary for <a #click='search("one people")'>one people</a> to dissolve the <a #click='search("political bands")'>political bands</a> which have connected
This is what I have tried so far though the click handler is not registered and the function never gets called:
<v-flex xs10 v-html="addlink(context.context, context.chunks)"></v-flex>
and in my methods section:
addlink: function(words, matchterms){
for(var index in matchterms){
var regquery = matchterms[index].replace(this.regEscape, '\\$&');
var query = matchterms[index];
var regEx = new RegExp(regquery, "ig");
words = words.replace(regEx, '<a href=\'#\' v-on:click.prevent=\'doSearch("'+ query +'")\'>' + query + '</a>');
}
return words;
}
As I said, this does not work and I know why. This is just showing that because of the nature of the problem is seems like regex is the correct solution but that gets me into a v-html injection situation. Is there something I can do in Vue to register the event handlers or can some one tell me a better way to load this data so I keep my links inline with the sentence and make them functional as well?
I've already posted one answer but I've just realised that there's a totally different approach that might work depending on your circumstances.
You could use event delegation. So rather than putting click listeners on each <a> you could put a single listener on the wrapper element. Within the listener you could then check whether the clicked element was an <a> (using event.target) and act accordingly.
Here's one way you could approach it:
<template>
<div>
<template v-for="segment in textSegments">
<a v-if="segment.link" href="#" #click.prevent="search(segment.text)">
{{ segment.text }}
</a>
<template v-else>
{{ segment.text }}
</template>
</template>
</div>
</template>
<script>
export default {
data () {
return {
"context": "When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected",
"chunks": ['human events', 'one people', 'political bands']
}
},
computed: {
textSegments () {
const chunks = this.chunks
// This needs escaping correctly
const re = new RegExp('(' + chunks.join('|') + ')', 'gi')
// The filter removes empty strings
const segments = this.context.split(re).filter(text => text)
return segments.map(segment => {
return {
link: segment.match(re),
text: segment
}
})
}
},
methods: {
search (chunk) {
console.log(chunk)
}
}
}
</script>
I've parsed the context text into an array of segments that can then be handled cleanly using Vue's template syntax.
I've used a single RegExp and split, which will not discard matches if you wrap them in a capture group, (...).
Going back to your original example, v-html only supports native HTML, not Vue template syntax. So you can add events using onclick attributes but not #click or v-on:click. However, using onclick wouldn't provide easy access to your search method, which is scoped to your component.
I'm having a look at Vue.js with a view to simplifying an application which is starting to get a bit too complex with jQuery. I want to utilise the data binding so that the state of an 'Order' object automatically enables or disables certain buttons (e.g., I want the submit button to be automatically disabled unless an order, containing items, exists). I have something which partly works, with this declaration:
var content = new Vue({
el: '#content',
computed: {
orderExists: function () {
return (shopOrder != null && !isEmpty(shopOrder.items));
}
}
});
I use it in a button like this:
<button type="button" id="btnDisplay" v-bind:disabled="!orderExists">Show Selected</button>
On page load, the buttons using this technique are indeed enabled/disabled correctly. However, when I add items to the order object, thereby changing its state, I'm not seeing any update in the buttons' states - they should be being enabled.
I assume I'm misunderstanding something basic about how this works with Vue.js, as I've only spent a couple of hours with it, so any help would be appreciated.
Hmmm why not pass the property as reactive data?
You can do something like:
...
computed: {
orderExists: function () {
this.disabled = (shopOrder != null && !isEmpty(shopOrder.items));
}
}
Fiddle.
DP: the example is in Vue 2
The issue is that Vue has to manage your data objects in order to set them up in a way where it can observe the changes to them (i.e. be made reactive). This is done by specifying the data option to your Vue creation. Something like:
data: {
shopOrder: null
}
Then update your code like this:
orderExists: function () {
return (this.shopOrder != null && !isEmpty(this.shopOrder.items));
}
And of course at some point you need to set this.shopOrder to a valid order object.