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<h1>Todo</h1>
<form id="todo-form">
<label for="todo-item">What do you need to do?</label>
<input type="text" name="todo-item" id="todo-item">
<button class="btn" id="add-todo">Add Todo</button>
</form>
<div id="app"></div>
/**
* Add box sizing to everything
* @link http://www.paulirish.com/2012/box-sizing-border-box-ftw/
*/
*,
*:before,
*:after {
box-sizing: border-box;
}
/**
* Layout
*/
body {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif;
font-size: 112.5%;
margin-left: auto;
margin-right: auto;
max-width: 40em;
width: 88%;
}
/**
* Forms
*/
label,
[type="text"] {
display: block;
width: 100%;
}
label {
margin-bottom: 0.25em;
}
[type="text"] {
font-size: inherit;
margin-bottom: 1em;
padding: 0.25em 1em;
}
[type="checkbox"] {
margin-right: 0.5em;
}
/**
* Buttons
*/
.btn {
background-color: #0088cc;
border: 1px solid #0088cc;
border-radius: 1px;
color: #ffffff;
display: inline-block;
font-size: 0.9375em;
font-weight: normal;
line-height: 1.2;
margin-right: 0.3125em;
margin-bottom: 0.3125em;
padding: 0.5em 0.6875em;
}
.btn:hover,
.btn:focus,
.btn:active {
background-color: #005580;
border-color: #005580;
color: #ffffff;
text-decoration: none;
}
/**
* Todos
*/
.todos {
list-style: none;
margin-left: 0;
padding-left: 0;
}
.todos .completed {
text-decoration: line-through;
}
.todo:before,
.todo:after {
display: table;
content: " ";
}
.todo:after {
clear: both;
}
.todo label {
width: auto;
}
.todo label,
.todo button {
float: left;
}
.todo button {
margin-left: 0.5em;
}
//
// Variables
//
var todoField = document.querySelector('#todo-item');
var todo;
//
// Methods
//
/**
* Save todo items to local storage
*/
var saveTodos = function () {
localStorage.setItem('todos', JSON.stringify(todo.data.todos));
};
/**
* Get todo items from local storage
* @return {Array} The todo items (or an empty array if none exist)
*/
var getTodos = function () {
var todos = localStorage.getItem('todos');
if (todos) return JSON.parse(todos);
return [];
};
/**
* Setup the initial todo list container
*/
var setup = function () {
// Create the todo list
todo = new Reef('#app', {
data: {
todos: getTodos()
},
template: function (props) {
// Create each todo item
var template = props.todos.map(function (todo, index) {
// If it's being edited, show a form
if (todo.edit) {
return `
<li class="todo">
<form class="todo-edit-form">
<input type="text" class="todo-update" value="${todo.item}" data-todo-edit="${index}">
<button>Save</button>
</form>
</li>`;
}
// Otherwise, show the item with a checkbox
return `
<li class="todo">
<label ${todo.completed ? 'class="completed"' : ''}>
<input data-todo="${index}" type="checkbox" ${todo.completed ? ' checked="checked"' : ''}>
<span class="todo-item">${todo.item}</span>
</label>
<button class="todo-edit">Edit</button>
<button class="todo-delete">Delete</button>
</li>`;
}).join('');
// If there are todo items, wrap it in an unordered list
if (template.length > 0) {
return `<ul class="todos">${template}</ul><p><button class="todo-clear">Clear All Todos</button></p>`;
}
return '';
}
});
// Render the todo list
todo.render();
};
/**
* Add a todo to the list
*/
var addTodo = function (event) {
// Only run if there's an item to add
if (todoField.value.length < 1) return;
// Prevent default form submission
event.preventDefault();
// Update the state
todo.data.todos.push({
item: todoField.value,
completed: false
});
// Clear the input field and return to focus
todoField.value = '';
todoField.focus();
};
/**
* Mark a todo as complete (or incomplete)
* @param {Node} item The todo item
*/
var completeTodo = function (item) {
// Get the todo item
var todoItem = todo.data.todos[item.getAttribute('data-todo')];
if (!todoItem) return;
// If it's completed, uncomplete it
// Otherwise, mark is as complete
if (todoItem.completed) {
todoItem.completed = false;
} else {
todoItem.completed = true;
}
};
/**
* Delete a todo list item
* @param {Node} btn The delete button that was clicked
*/
var deleteTodo = function (btn) {
// Get the index for the todo list item
var index = btn.closest('.todo').querySelector('input').getAttribute('data-todo');
if (!index) return;
// Remove the item from state
todo.data.todos.splice(index, 1);
};
/**
* Edit a todo list item
* @param {Node} btn The edit button that was clicked
*/
var editTodo = function (btn) {
// Get the todo list DOM element
var todoListItem = btn.closest('.todo');
if (!todoListItem) return;
// Get the index for the item
var index = todoListItem.querySelector('input').getAttribute('data-todo');
if (!index) return;
// Get the item from state
var todoItem = todo.data.todos[index];
if (!todoItem) return;
// Update state
todoItem.edit = true;
};
var saveEditTodo = function (event) {
// Prevent default form submit
event.preventDefault();
// Get the todo list DOM node
var newTodo = event.target.querySelector('.todo-update');
if (!newTodo) return;
// Get the todo list item index
var index = newTodo.getAttribute('data-todo-edit');
if (!index) return;
// Get the item from state
var todoItem = todo.data.todos[index];
if (!todoItem) return;
// If the item is empty, delete the todo item
// Otherwise, update it
if (newTodo.value.length < 1) {
todo.data.todos.splice(index, 1);
} else {
todoItem.item = newTodo.value;
todoItem.edit = false;
}
};
/**
* Remove all todo items from state
*/
var clearTodos = function () {
// Replace the existing state with an empty array
todo.data.todos = [];
};
/**
* Handle click events
*/
var clickHandler = function (event) {
// Complete todos
var todo = event.target.closest('[data-todo]');
if (todo) {
completeTodo(todo);
};
// Edit todo
var editBtn = event.target.closest('.todo-edit');
if (editBtn) {
editTodo(editBtn);
}
// Delete todo
var deleteBtn = event.target.closest('.todo-delete');
if (deleteBtn) {
deleteTodo(deleteBtn);
}
// Clear all todos
if (event.target.closest('.todo-clear')) {
clearTodos();
}
};
/**
* Handle form submit events
*/
var submitHandler = function (event) {
// If it's the "new todo" form, add the item
if (event.target.matches('#todo-form')) {
addTodo(event);
}
// If it's the "edit todo" form, save the edit
if (event.target.matches('.todo-edit-form')) {
saveEditTodo(event);
}
};
/**
* Handle render events
*/
var renderHandler = function (event) {
// If the rendered element is not the #app, bail
if (!event.target.matches('#app')) return;
// Save the current state to localStorage
saveTodos();
};
//
// Inits & Event Listeners
//
// Setup the DOM
setup();
// Listen for events
document.addEventListener('submit', submitHandler, false);
document.addEventListener('click', clickHandler, false);
document.addEventListener('render', renderHandler, false);
Also see: Tab Triggers