What it means to subscribe to events?

Subscription to list events in Skeleton.js means firing callback functions when a specified event occures. This is very usefull for updating parts of the DOM that are dependent on list actions.

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For instance, when we 'push' or 'edit' a todo, we want to filter our todo list again:

TodosList.subscribe(['push','edit'], () => {
    let filter = Skeleton.storage.fetch('filter') || 'all';
    window.filterTodos(filter);
});

When we 'push','remove','edit','removeAll', we want to update the size of our todo list we show the user, and resave our todos in the browser localStorage:

TodosList.subscribe(['push','remove','edit','removeAll'], () => {
    updateSize();
    Skeleton.storage.save({ 
        todos: TodosList.models() 
    });
});

Finally, when we push an array of todos, we want to update the size of the todo list we show the user:

TodosList.subscribe('pushAll', updateSize);