So inside my reducer, I have an array of objects called 'todos', and an object of 'todos' has a state which is also an array of objects, called 'comments'. And inside each of 'comments' array, I would like to define a string state 'commentText', but I can't seem to figure out how to do so. Any help would be greatly appreciated.
Following is an example of what I would like to achieve:
let todoReducer = function(todos = [], action){
switch(action.type){
case 'ADD_TODO':
return [{
comments:[{
commentText: action.commentText
}]
}, ...todos]
case 'CREATE_COMMENT_ARRAY':
return [{
commentText: action.eventValue
], ...todos.comments] //Referencing todos.comments as 'comments' array of objects of an object of 'todos' array. Would like to directly update if possible and build up 'comments' array.
default:
return todos
}
}
export default todoReducer
NEW EDIT**:
case 'UPDATE_COMMENT':
return todos.map(function(todo){
if(todo.id === action.id){
//want to add a new a 'comment' object to the todo's 'comments' array
//Something like the following:
todo.comments: [{
commentText: action.commentText
}, ...todo.comments]
}
})
This sounds like a great use case for the .map()
Array method.
Assuming your data looks like this:
var todos = [
{
id: 1,
title: 'Todo 1 Title',
body: 'Todo 1 Body',
date: 1425364758,
comments: [
{
id: 1,
commentorId: 42069,
text: 'Todo 1, Comment 1 Text',
date: 1425364758
},
{
id: 2,
commentorId: 42069,
text: 'Todo 1, Comment 2 Text',
date: 1425364758
},
{
id: 3,
commentorId: 42069,
text: 'Todo 1, Comment 3 Text',
date: 1425364758
}
]
},
{
id: 2,
title: 'Todo 2 Title',
body: 'Todo 2 Body',
date: 1425364758,
comments: [
{
id: 1,
commentorId: 42069,
text: 'Todo 2, Comment 1 Text',
date: 1425364758
}
]
},
{
id: 3,
title: 'Todo 3 Title',
body: 'Todo 3 Body',
date: 1425364758,
comments: [
{
id: 1,
commentorId: 42069,
text: 'Todo 3, Comment 1 Text',
date: 1425364758
},
{
id: 2,
commentorId: 42069,
text: 'Todo 3, Comment 2 Text',
date: 1425364758
}
]
}
];
When updating a comment, you'd need to pass in a todoId
and a commentId
so you know what to look for. When adding a comment, you'd only need to pass in a todoId
so you know which todo to update:
const todoReducer = (todos = [], action) => {
switch(action.type) {
case 'ADD_TODO':
return [
action.todo,
...todos
];
case 'ADD_COMMENT':
const { todoId, comment } = action;
// Map through all the todos. Returns a new array of todos, including the todo with a new comment
return todos.map(todo => {
// Look for the todo to add a comment to
if (todo.id === todoId) {
// When the todo to update is found, add a new comment to its `comments` array
todo.comments.push(comment);
}
// Return the todo whether it's been updated or not
return todo;
});
case 'UPDATE_COMMENT':
const { todoId, commentId, commentText } = action;
// Map through all the todos. Returns a new array of todos, including the todo with the updated comment
return todos.map(todo => {
// First find the todo you want
if (todo.id === todoId) {
// Then iterate through its comments
todo.comments.forEach(comment => {
// Find the comment you want to update
if (comment.id === commentId) {
// and update it
comment.text = commentText;
}
});
}
// Return the todo whether it's been updated or not
return todo;
});
default:
return todos;
}
};
export default todoReducer;
As for your payloads, you can make them whatever you want, and they'll be created in your action creator. For example, here's an implementation of ADD_TODO
that gives the todo a unique ID, timestamps it, and adds an empty comments
array before firing the action:
import uuid from 'node-uuid';
const addTodo = ({title, body}) => {
const id = uuid.v4();
const date = new Date().getTime();
return {
type: 'ADD_TODO',
todo: {
id,
title,
body,
date,
comments: []
}
};
};
Your ADD_COMMENT
action creator might look something like this:
import uuid from 'node-uuid';
const addComment = ({todoId, commentorId, commentText}) => {
const id = uuid.v4();
const date = new Date().getTime();
return {
type: 'ADD_COMMENT',
todoId,
comment: {
id,
commentorId,
date,
text: commentText
}
};
};
This is untested but hopefully gives you an idea.
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