Global communication between components

Sugar (Super global artifacts)

When working with numerous components, it's not uncommon for a self method or property to be required across the application. LemonadeJS Sugar addresses this issue by creating a global registry allowing a self or function to be registered and made available across different scopes.

Summary of this chapter
This document highlights several aspects of Sugar:
  • Make a self available across various components using Sugar's set and get methods.
  • Use the data dispatcher to act on a self property while preserving its private scope.
  • Register data dispatcher actions and call them from any component.
  • Leverage the persistence flag to save the latest data dispatched for a specific Sugar alias.


Example

In the following example, the self is registered on the Profile component and recovered on the Loader component.

<html>
<script src="https://lemonadejs.net/lemonade.js"></script>
<div id='profile'></div>
<div id='loader'></div>
<script>
function Profile() {
    // Create a blank self
    const self = this;

    // Register the self under My:Profile alias
    lemonade.set('My:Profile', self);

    // Counter is created from the attribute counter
    return `<form>
        <label>Name:</label><br/>
        <input type="text" :bind="self.name" /><br/>
        <label>Email:</label><br/>
        <input type="text" :bind="self.email" />
    </form>`;
}

function Loader() {
    const self = this;
    self.load = function() {
        // Get My:Profile self
        let s = lemonade.get('My:Profile');

        // Updates directly to the self properties
        s.name = 'John Lennon';
        s.email = 'john.lennon@beatles.com';
    }

    return `<input type="button" value="Load the data" onclick="self.load()" />`;
}
lemonade.render(Profile, document.getElementById('profile'));
lemonade.render(Loader, document.getElementById('loader'));
</script>
</html>

Profile



Loader



Data Dispatcher

Sometimes, you might not want the entire self to be accessible but still need to update the state of specific properties of one {self} from other components. A solution for this scenario is registering a data dispatcher function with LemonadeJS Sugar.

A basic example of persistence

To illustrate this concept, we'll use an example similar to the one above, utilizing the persistence flag to maintain the last dispatched data saved, even after a page refresh.

<html>
<script src="https://lemonadejs.net/lemonade.js"></script>
<div id='profile'></div>
<div id='loader'></div>
<script>
function Profile() {
    // Create a blank self for this component
    const self = this;

    // Register the dispatcher under Profile
    // and set the persistence as true
    lemonade.set('Profile', function(s) {
        self.name = s.name;
        self.email = s.email;
    }, true);

    // The template create the form elements
    return `<form>
        <label>Name:</label><br/>
        <input type="text" :bind="self.name" /><br/>
        <label>Email:</label><br/>
        <input type="text" :bind="self.email" />
    </form>`;
}

function Loader() {
    const self = this;
    self.dispatch = function() {
        // Send new values to another component using the dispatcher
        lemonade.dispatch('Profile', {
            name: 'John Lennon',
            email: 'john.lennon@beatles.com',
        });
    }

    return `<input type="button" value="Load" onclick="self.dispatch()" />`;
}
lemonade.render(Profile, document.getElementById('profile'));
lemonade.render(Loader, document.getElementById('loader'));
</script>
</html>

Profile



Loader