Nativescript-Vue-Dynamo

Nativescript-Vue-Dynamo is a dynamic component router implementation that is suitable for NativeScript-Vue.

It uses Vue Dynamic Components to simulate the normal navigation patterns of a Nativescript-Vue app. It does this by plugging into Vue-Router and Vuex. This implementation also supports "Child Routes" by using the same Dynamic Component behavior, in a nested manner, to allow you to navigate within the parent/child routes.

To be clear: we are not actually using the underlying mechanics of Vue-Router to navigate through the app as this has been problematic issue when trying to use Nativescript-Vue historically. However, we are doing things like plugging into the main Route Config as a common shared configuration and then using a router.afterEach hook to update the route history that we are keeping in the state manager. When the route history state changes, the dynamic components will cause the app to load a new route or Page. This effectively mimcs normal navigation patterns.

A further point must be made: we are also not using the underlying mechanics of Nativescript-Vue to navigate. There is no $navigateTo or $navigateBack going on. Thus, we keep something similar to Nativescript's navigation stack inside of our state manager so that we can track forwards and backwards movement as needed.

This project takes many of the same ideas in Vuex-Router-Sync and Nativescript-Vue-Navigator and combines them in a way that simulates the traditional routing experience withing a Nativescript-Vue app.

Quick Start

``shell
npm install --save nativescript-vue-dynamo
`

Main entry point (main.js or main.native.js)

`js
import Vue from 'nativescript-vue';
import App from './App.vue';
import store from './store';
import router, { routes } from './router';

import Dynamo from 'nativescript-vue-dynamo';
Vue.use( Dynamo, {
store,
router,
routes,
});
`

Vue-Router Config

Inside or your Vue-Router config, you will want to split out your route config into it's own array as modeled below. You can then use many of the extra options provided by Vue-Router out of the box such as adding the meta object. Most built in router hooks should be available to help assist you as well. Notice the routeHistoryName in the meta tags for all routes. Also, for child routes, notice the parentRouteHistoryName. These two items should be used in this manner to help assist Dynamo with tracking where it is at and where it needs to go. Finally, also notice the alias property in the first child route. This helps tell Dynamo which child route is the default child route.

`js
export const routes = [
{
name: 'home',
path: '/home',
component: () => import(/ webpackChunkName: "home" / '~/views/Home'),
meta: {
title: 'Home',
auth: true,
routeHistoryName: 'main',
},
},
{
name: 'login',
path: '/login',
component: () => import(/ webpackChunkName: "login" / '~/views/Login'),
meta: {
title: 'Login',
auth: false,
routeHistoryName: 'main',
},
},
{
name: '',
path: '/first',
component: () => import(/ webpackChunkName: "first" / '~/views/First'),
props: true,
meta: {
title: 'First',
auth: true,
routeHistoryName: 'main',
},
children: [
{
name: 'dynamo-one',
alias: '/',
path: '/dynamo-one',
component: () => import(/ webpackChunkName: "dynamo-one" / '~/views/Dynamo-One'),
meta: {
title: 'Dynamo One',
auth: true,
routeHistoryName: 'first',
parentRouteHistoryName: 'main',
},
},
{
name: 'dynamo-two',
path: '/dynamo-two',
component: () => import(/ webpackChunkName: "dynamo-two" / '~/views/Dynamo-Two'),
meta: {
title: 'Dynamo Two',
auth: true,
routeHistoryName: 'first',
parentRouteHistoryName: 'main',
},
},
],
}
]
`

App.vue

Inside of your App.vue, you can do something simple as below. Notice we are sending two required props into the component:

1. defaultRoute - This will make sure that the first page loaded is the one specified by this value. It must also match an actual route in your router config.
2. routeHistoryName - This name will end up being the id of the frame/div loaded and will also be used to track via state manager which frame/div we are navigating within.

These two options are mandatory for this package to work correctly.

`html

`

Inside of App.vue, you could even provide your own wrapper around the Dynamo component. This could be a StackLayout or any of the other layout components such as GridLayout. Just be aware that any alternative layout items will not be replaced when the Dynamo component updates itself. This might be useful if you want a bottom navigation button area and then have the buttons selected switch out the item in the first row of the Grid:

`html

`

Navigating

Because we are plugging into Vue-Router, many of the same programmatic navigation aides available there should be usable within Nativescript-Vue. So things like route.push() and route.back() should work. Others may not and if you find something that is not working, please submit an issue.

In the example above, we are providing two different ways to route within the $goTo navigation aide. Refer to the Navigation Aides section below for more information about this function.
The first passes an object that should look similiar to something you pass for a route.push with vue-router, while the second also passes params to the route. Any params passed to the route will be forwarded on to the route as a prop. This allows you to dynamically pass props to your route.

$3

You can use "child route" like features as well. You will build out your child route config as you normally would with Vue-Router except you must add a meta tag into the child route's config:

`json
meta: {
title: 'Dynamo One',
auth: true,
routeHistoryName: 'first',
parentRouteHistoryName: 'main',
},
`

By adding the meta take and then adding the parentRouteHistoryName property you will effecively activate the parent/child relationship between components and this will mimic many of the parent/child functions of Vue-Router. Notice that the parentRouteHistoryName property is equal to the previously used routeHistoryName and routeHistoryName is now something entirely different. You would then just add a Dynamo component into the Parent view as normal. Notice the routeHistoryName in the route config above matches the routeHistoryName prop in the component below.

`html

`

You can also provide an option of simulating Nativescript's built in clearHistory navigation option. You can provide a route parameter named clearHistory and this will reset the route history state for the corrosponding routeHistoryName.

For example, given you are on a Login page, and successfully log in you would navigate to the Home page with

`js
$router.push({ name: 'home', params: { routeHistoryName: 'main', clearHistory: 'true'}});
`

or

`js
this.$goTo('home', true);
`

Note that we used clearHistory: true to prevent the back button from going back to the login page or just passed true as the 2nd prop in this.$goTo.

Optional Navigation Aides

This package is also providing some additional Navigation Aides via Vue.prototype that will help assist you navigating within your app.

1. $goTo(location, routeHistoryName, parentRouteHistoryName?, clearHistory?, onComplete?, onAbort?)

Parameter | Type | Required | Purpose
------------ |:-------------:|:-------------:| -------------
location | string or Location | X | Where you want to go. If this is a string, then it will navigate to that route. If it is a vue-router Location Object, then it will take the included options into account when navigating.
clearHistory | boolean | | clear the navigation history being kept in the state manager. Will default to false
onComplete | Function | | Callback to be called when the navigation successfully completes (after all async hooks are resolved).
onAbort | Error Handler | | Callback for when the navigation is aborted (navigated to the same route, or to a different route before current navigation has finished)

For convience we are constructing a router.push behind the scenes. We did this as a matter of convience since we are adding a required route parameter as well as some optional route parameters to help us track navigation. You could just as easily still use router.push if you want as seen in the Login example above.
2. $goBack() - It will check to see if you are navigating back to a sibling route, or going backwards to a parent route. It will also check to see if this is the last page left in the frame and if there is a parent route, it will transition to it.
3. $goBackToParent(routeHistoryName, parentRouteHistoryName) - Provide the child routeHistoryName and the parentRouteHistoryName and it will navigate back up the route tree. This method is actually called for you if when you use $goBack() and there is a need to transition backwards to a parent Route.

Event Handling and Refs

The Dynamo component is acting as a "middle-man" between the components you are concerned with. Thus, the relationship looks something like this Parent -> Child(Dynamo) -> Grandchild. This means you won't be able to handle events or use refs to call functions on the grandchild as you normally would. Because of this, we have provided a way to handle both of these common patterns.

$3

When you call the Dynamo component, you can add an additional parameter that has a very specific way of referencing it whereby it must include the routeHistoryName within it. Notice that with the v-on we are including first as the first string in the kebab case name. The pattern you will need to use is "routeHistoryName + -event-handler". This lets Dynamo know which parent component to bubble the event up to.

`html
:routeHistoryName="'first'"
:defaultRoute="'dynamo-one'"
:functionHandler="functionHandler"
@first-event-handler="eventHandler"
/>
`

Then inside your parent component you can include a function similar to this:

`js
public eventHandler(e){
console.log('first.vue - eventHandler - ', e);
}
`

Inside your grandchild component you can then emit an event as you normally would: this.$emit('dynamo-event', "emit event one");. Notice the event name is dynamo-event. This is the required event name as it is hard coded into the Dynamo component.

In theory, you can use this single event handler to do multiple things in the parent component via something like a switch statement, or even get more advanced and pass an object back up through the event and convert it into calling a method somewhere else. Here's an example object: { function: 'anotherMethod', data: 'data' } and then within your eventHandler function you could do something like below and it would automatically call your anotherMethod method and pass it the data:

`js
public eventHandler(e){
thise.function
}
`

#### Refs & calling grandchild functions

In your Dynamo component you can include an option named functionHandler and then have it reference a property in your parent component. In reality what we are doing is passing a Prop to the Dynamo component which in turn is passing that Prop down to the grandchild component.

For the sake of convienence, we've named the function functionHandler in the example below.

`html
:routeHistoryName="'first'"
:defaultRoute="'dynamo-one'"
:functionHandler="functionHandler"
@first-event-handler="eventHandler"
/>
`

Then you could do something like below inside your script tag's export. The parentButton method is just a convience provided in the example that is called after a button click. In turn, the parentButton method replaces the value of this.functionHandler. The object provided works much like the eventHandler example above, but in reverse. It references a method to call on the grandchild: parentToChild and some data to pass to the grandchild's method.

`js
public functionHandler: object = {};

public parentButton() {
console.log('parentButton clicked');
this.functionHandler = { method: 'parentToChild', data: 'hello there' };
}
`

Then inside your grandchild component you could do something like below. Notice we've setup the Prop but also setup a watcher. This allows us to use this single Prop to act as a gateway to calling multiple methods in the grandchild component. Think of it as a one-to-many relationship. Inside the watcher we've included an example where we dynamically call other methods.

In the example above, we are passing in parentToChild as the method to call with the data of hello there. This means in the example below, we will write the following to the console: parentToChild - hello there. Also notice we've included an example of emitting an event back up as well. This is optional and is not necessary.

`js
@Prop() functionHandler: object = {};
@Watch('functionHandler')
onfunctionHandlerChanged(val: Function) {
thisval.method;
}

public parentToChild(data: string) {
console.log('parentToChild - ', data);
this.$emit('dynamo-event', "emit event two from parentToChild function");
}
`

Demo project

Take a look at the demo project for a simplistic project that implements this plugin with many of the examples discussed above. Notice within the utils/global-mixin-native class file there is an example of intercepting the Android back button behavior and then plugging it into the $goBack()` navigation aide.