I'm working on my First project with React, I have an App and a ToDo. I am defining a deleteToDo
method and I want the method to call this.setState()
and pass it a new array that doesn't have the to-do item being deleted with the use of the .filter()
array method. I don't want to alter the code to much or introduce more complexity. In essence I would like to keep it as straight forward as possible. I am still a beginner with React so this has been a big learning process. I feel that I am close.
This is the main app
import React, { Component } from 'react';
import './App.css';
import ToDo from './components/ToDo.js';
class App extends Component {
constructor(props) {
super(props);
this.state = {
todos: [
{ description: 'Walk the cat', isCompleted: true },
{ description: 'Throw the dishes away', isCompleted: false },
{ description: 'Buy new dishes', isCompleted: false }
],
newTodoDescription: ''
};
}
deleteToDo(index) {
const todos = this.state.todos.slice();
const todo = todos[index];
todo.deleteToDo = this.state.filter(index);
this.setState({ todos: todos });
}
handleChange(e) {
this.setState({ newTodoDescription: e.target.value })
}
handleSubmit(e) {
e.preventDefault();
if (!this.state.newTodoDescription) { return }
const newTodo = { description: this.state.newTodoDescription, isCompleted: false };
this.setState({ todos: [...this.state.todos, newTodo], newTodoDescription: '' });
}
toggleComplete(index) {
const todos = this.state.todos.slice();
const todo = todos[index];
todo.isCompleted = todo.isCompleted ? false : true;
this.setState({ todos: todos });
}
render() {
return (
<div className="App">
<ul>
{ this.state.todos.map( (todo, index) =>
<ToDo key={ index } description={ todo.description } isCompleted={ todo.isCompleted } toggleComplete={ this.toggleComplete } deleteToDo={ this.deleteToDo } />
)}
</ul>
<form onSubmit={ (e) => this.handleSubmit(e) }>
<input type="text" value={ this.state.newTodoDescription } onChange={ (e) => this.handleChange(e) } />
<input type="submit" />
</form>
</div>
);
}
}
export default App;
And this the ToDo aspect
import React, { Component } from 'react';
class ToDo extends Component {
render() {
return (
<li>
<button type="button" onClick={ this.props.deleteTodo} > delete </button>
<input type="checkbox" checked={ this.props.isCompleted } onChange={ this.props.toggleComplete } />
<span>{ this.props.description }</span>
</li>
);
}
}
export default ToDo;
You slice and array without the index, that's may be why your delete not work
deleteToDo(index) {
const todos = this.state.todos.slice(index, 1);
this.setState({ todos: todos });
}
1) You need to bind your deleteToDo
method in the constructor
this.deleteToDo = this.deleteToDo.bind(this);
2) You need to set a new property on the component that is the same as its index.
<ToDo
key={index}
id={index}
description={ todo.description }
// ...
/>
3) Then you can pass that index as the argument to deleteToDo
(making sure you spell the method name correctly).
<button
type="button"
onClick={() => this.props.deleteToDo(this.props.index)}
>Delete
</button>
4) Finally, you can strip down your deleteToDo
method to the following:
deleteToDo(index) {
// Return a new array that doesn't
// have a row with a matching index
const todos = this.state.todos.filter((el, i) => i !== index);
this.setState({ todos });
}
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