AngularJS学习笔记之TodoMVC的分析_AngularJS

/*global angular */
/*jshint unused:false */
'use strict';
/**
* The main TodoMVC app module
*
* @type {angular.Module}
*/
var todomvc = angular.module('todomvc', []);

/*global todomvc */
'use strict';
/**
* Services that persists and retrieves TODOs from localStorage
*/
todomvc.factory('todoStorage', function () {
// todos JSON字符串存储的唯一标识
var STORAGE_ID = 'todos-angularjs';
return {
// 从localStorage中取出todos，并解析成JSON对象
get: function () {
return JSON.parse(localStorage.getItem(STORAGE_ID) || '[]');
},
// 将todos对象转化成JSON字符串，并存入localStorage
put: function (todos) {
localStorage.setItem(STORAGE_ID, JSON.stringify(todos));
}
};
});

/*global todomvc */
'use strict';
/**
* Directive that places focus on the element it is applied to when the expression it binds to evaluates to true
*/
todomvc.directive('todoFocus', function todoFocus($timeout) {
return function (scope, elem, attrs) {
// 为todoFocus属性的值添加监听
scope.$watch(attrs.todoFocus, function (newVal) {
if (newVal) {
$timeout(function () {
elem[0].focus();
}, 0, false);
}
});
};
});

/*global todomvc */
'use strict';
/**
* Directive that executes an expression when the element it is applied to gets
* an `escape` keydown event.
*/
todomvc.directive('todoEscape', function () {
var ESCAPE_KEY = 27;
return function (scope, elem, attrs) {
elem.bind('keydown', function (event) {
if (event.keyCode === ESCAPE_KEY) {
scope.$apply(attrs.todoEscape);
}
});
};
});

/*global todomvc, angular */
'use strict';
/**
* The main controller for the app. The controller:
* - retrieves and persists the model via the todoStorage service
* - exposes the model to the template and provides event handlers
*/
todomvc.controller('TodoCtrl', function TodoCtrl($scope, $location, todoStorage, filterFilter) {
// 从localStorage中获取todos
var todos = $scope.todos = todoStorage.get();

// 记录新的todo
$scope.newTodo = '';
// 记录编辑过的todo
$scope.editedTodo = null;
// 当todos的值改变时执行其中的方法
$scope.$watch('todos', function (newValue, oldValue) {
// 获取未完成的todos的数目
$scope.remainingCount = filterFilter(todos, { completed: false }).length;
// 获取已完成的todos的数目
$scope.completedCount = todos.length - $scope.remainingCount;
// 当且仅当$scope.remainingCount为0时，$scope.allChecked为true
$scope.allChecked = !$scope.remainingCount;
// 当todos的新值和旧值不相等时，向localStorage中存入todos
if (newValue !== oldValue) { // This prevents unneeded calls to the local storage
todoStorage.put(todos);
}
}, true);
if ($location.path() === '') {
// 如果$location.path()为空，就设置为/
$location.path('/');
}
$scope.location = $location;
// 当location.path()的值改变时执行其中的方法
$scope.$watch('location.path()', function (path) {
// 获取状态的过滤器
// 如果path为'/active'，过滤器为{ completed: false }
// 如果path为'/completed'，过滤器为{ completed: true }
// 否则，过滤器为null
$scope.statusFilter = (path === '/active') ?
{ completed: false } : (path === '/completed') ?
{ completed: true } : null;
});
// 添加一个新的todo
$scope.addTodo = function () {
var newTodo = $scope.newTodo.trim();
if (!newTodo.length) {
return;
}
// 向todos里添加一个todo，completed属性默认为false
todos.push({
title: newTodo,
completed: false
});
// 置空
$scope.newTodo = '';
};
// 编辑一个todo
$scope.editTodo = function (todo) {
$scope.editedTodo = todo;
// Clone the original todo to restore it on demand.
// 保存编辑前的todo，为恢复编辑前做准备
$scope.originalTodo = angular.extend({}, todo);
};
// 编辑todo完成
$scope.doneEditing = function (todo) {
// 置空
$scope.editedTodo = null;
todo.title = todo.title.trim();
if (!todo.title) {
// 如果todo的title为空，则移除该todo
$scope.removeTodo(todo);
}
};
// 恢复编辑前的todo
$scope.revertEditing = function (todo) {
todos[todos.indexOf(todo)] = $scope.originalTodo;
$scope.doneEditing($scope.originalTodo);
};
// 移除todo
$scope.removeTodo = function (todo) {
todos.splice(todos.indexOf(todo), 1);
};
// 清除已完成的todos
$scope.clearCompletedTodos = function () {
$scope.todos = todos = todos.filter(function (val) {
return !val.completed;
});
};
// 标记所有的todo的状态（true或false）
$scope.markAll = function (completed) {
todos.forEach(function (todo) {
todo.completed = completed;
});
};
});

todos

Mark all as complete

• 
  
  
  
  {{todo.title}}