I'm currently working on a sample application to learn Kotlin/Js with the react library. When using the normal JSX syntax, a component can be set to be triggered when a specific URL hits using the BrowserRouter & Route API like below.
Main Component
Navigation Component as directed like in this youtube video
When attempting the above code in Kotlin, it resembles something like the screenshot below using the KotlinDSL
The main function where the component is rendered is shown below
However, that creates an Uncaught Error Exception like the one below
One of the reasons its also so difficult to debug is because my source maps dont work and hence most of my debugging errors are actually in Javascript. But anyways after searching up the javascript error, I found this article about the new Router update that disallows adding components as children.
As a result I tried to pass in the components through the element prop but there seems to be some incompatibility with them.
the element prop accepts an optional ReactNode? and I cant seem to convert my Function Component of type props to a ReactNode. When I try to pass in an optional ReactElement? by calling the create method, I also get an error.
I have been struggling with the Kotlin Documentation and can't seem to find enough examples of react-router implemented.
Can anyone help me out with how to pass in a Function COmponent into the element prop for the React Router?
I'm building a Vue.js app that will be run on devices where I don't have access to a dev tools console, such as a game console. I've created a vue DebugPanel component that contains several tabs, one of them being a "log" to write to.
The UI is mostly working as I expect, but now I need to actually take what's in the console and have it output to the element in the component.
I'd like to use this solution of hijacking the consol.log function. This solution works great in a non-vue HTML page, but I'm having trouble with the best way to incorporate it into a Vue.js app.
The issue I'm having is that each tab section on my DebugPanel is hidden/shown based on a v-if attribute. The log element is only in the DOM when its tab element shown. So a call to document.getElementById errors.
Any thoughts on how to implement this in Vue.js?
You can just use Vuex store to pass data through all the app. And i think it would be better to use it in your app for global data.
I have installed VueJS chrome extension:
VueJS chrome extension
but I find it quite useless unless I am missing something. So I posted the question here if some one can provide what I am missing.
I setup this vuejs project:
Kazoo on github
This project has several vue components but most of these components do not show up in vuejs chrome extension. This is the screenshot:
The Vue devtools show the application as you are viewing it now (just like the DOM viewer shows you the DOM elements that are currently on the page). Clicking a component will show you the internal state of that component, such as props and data. This allows you to infer where a problem may be originating when you see a bug occur in your application. It also allows you to figure out if the correct components are being loaded. It does not show you components that are currently not in the document, as it would not be useful.
The vuex tab will allow you to inspect the entire store, and all mutations that have been done and with what payload since the vue devtools initialised. It will show you what is computed by the getters.
The Events tab will show you which events have been fired. This may be particularly nice if you have a framework that uses them, or if you use global events yourself.
I construct deep nested tree of parent and children Vue custom components using my top level component dynamically and then I am updating the data from which all tree is constructed. Which has an effect of rendering the entire tree (its a form with various custom components). I refresh/rebuild the whole form after fetching the data (which is what vue do for reactive data) that itself tell me how to regenerate the view (its like a JSON Schema from which I render the entire view).
This is related to my other issue here.
I am observing a very weird behavior in my Vue Application. When I destroy all my children components and rebuild the data to force rendering the form, it appears that even after I have called $destroy on every child component...Vue is not entirely removing them from cache?
Does vue remove the component from cache if a $destroy is called ?
Because I do not see multiple components of the same type in the Vue component list in the Chrome Vue DevTool extension panel. But I see that the same custom event is handled twice by the same component. Same function that handle the events is getting called twice even though there is only one component visible in Vue DevTools of this type.
This only happens after I render the form. When the page is loaded for the first time every thing works. Then after I reset the form by destroying the child component and resetting the data to re-render the form, magically this child component start handling the event twice.. and in 3rd render it handle the events thrice. But I see only one component in google chrome VueJS DevTool extension panel. So my guess is that vue is still keeping the previously destroyed component in cache. I am trying to figure out how should I destroy those components in the cache.
If anyone has observed something similar and found a solution please let me know.
At the moment I am going to dig little bit more on my component keys (this particular component does not have explicit key set by me).
First and foremost, the vue documentation states:
vm.$destroy
In normal use cases you shouldn’t have to call this method yourself.
Prefer controlling the lifecycle of child components in a data-driven
fashion using v-if and v-for.
So instead of destroying and rebuilding the components manually yourself, you should really letting vue handle that via v-if and v-for. If the components aren't updating to your changes, you might be dealing with a reactivity issue.
As you mentioned that this is a deeply nested structure, the reactivity is key to keeping the components up to data with the data.
Vue does not allow dynamically adding new root-level reactive properties to an already created instance. However, it’s possible to add reactive properties to a nested object using the Vue.set(object, key, value) method:
Vue.set(vm.someObject, 'b', 2)
Inside of a component:
this.$set(this.someObject, 'b', 2)
Also, keep in mind that Vue should be doing the heavy lifting in regards to component management, while you should define the parameters by which a component is rendered.
I'm new to vue js and have some questions when learning it.
I'm now a little confused about the relationship between its instance and component. As far as I learned, every app build by vue should only have one instance and one instance only, it can have as many components as you like if needed. But recently I've seen a demo, and in that demo it has more than one instance.
So my question is, is that ok to have multiple intances in one app( the demo code works fine, but is that the correct way)? What's the best practice to use instance and component in vue app?
It's ok to have two instances in the same project, however, you probably don't want to do that.
A good scenario is to have one main instance to control your app, specially if you are creating a Single Page Application (SPA). Then use as many components as you want.
Components are a great way to reuse code and keep it organized, and, with Vue.js, is very easy to communicate between your components and your "main" Vue instance.
It depends very much on your situation.
I work on a large web project which is not an SPA. We have a Vue instance for each "silo" of the application. We are slowly transitioning an older project from a mostly jQuery frontend so it's possible that as it evolves We'll be able to condense down to a single Vue instance but we're having no trouble with multiple instances. The ease of using Vue in existing projects was one of the biggest deciding factors in choosing it over another library such as react.
I have taken a different approach with green development, one instance and many components.
There are something in common, and some difference between Vue instance and Vue component.
From Vue docs:
all Vue components are also Vue instances, and so accept the same options object (except for a few root-specific options).
The root Vue instances accept properties like el, router, the Vue components cannot.
The data property in root Vue instances is an object, but in Vue components must be a function.
The design target is different:
A root Vue instance is a Vue application launcher, Vue component is an extension of the Vue instance.
Vue components can create elements to be reused in many places. This is Vue characteristic of componentization mainly reflect point.
Vue instance can associated with and manipulate an element which is already exist.
Vue component more suitable for create new element and reuse it at anywhere.
Think of a Vue Component as a blueprint or set of rules on how to create something that can be inserted into the DOM that the user can interact with.
So when you create a Vue file you are going to define exactly one component with a set of rules that tells Vue how to display stuff on the screen and tells a user how to interact with it.
On the other hand is a Vue instance, its an instance of a Vue component, it represents something that has been inserted into the DOM and is something that a user can interact with.
If you have a background in Object-Oriented Programming, think of a Vue Component as being like a class and a Vue instance as an instance of that class.
What has not been mentioned in previous answers that I will cover in regards to the difference between Vue instance and Vue component is how we define the data property that we are working with.
If we are working with a Vue instance, then we can define the data property as an object or a function that returns an object like so:
With a Vue Component that data property must be a function that returns an object.
So for example this is a Vue component:
export default {
name: "App",
components: {
SearchBar,
VideoList
},
And if we want to make use of data inside of that Vue component, we have to make a function that returns an object.
Vue components extends Vue instances
but Vue instances accept properties like el, router, the Vue components cannot.
best practice:
one Vue instance
many Vue component