remove-item.md

Remove item

The user should be able to remove any item, whether it's still active or completed. Removing an item will be done by clicking a button, aptly named "remove". In this chapter, we'll learn how to add this functionality to our project.

Add the "remove" button

First, we need to add the button to the item, so we'll work on the file todo-item.component.ts.

Add a "remove" button to the item template, with a click event handler that calls a removeItem method (which we'll create in a moment):

{% code-tabs %} {% code-tabs-item title="src/app/todo-item/todo-item.component.ts" %}

template: `
  <div class="todo-item">
    {{ item.title }}

    <button class="btn btn-red" (click)="removeItem()">
      remove
    </button>
  </div>
`,

{% endcode-tabs-item %} {% endcode-tabs %}

Add a new output to the TodoItemComponent class, which will emit the removed item to the list manager when a user presses its remove button:

{% code-tabs %} {% code-tabs-item title="src/app/todo-item/todo-item.component.ts" %}

@Output() remove: EventEmitter<TodoItem> = new EventEmitter();

{% endcode-tabs-item %} {% endcode-tabs %}

Make sure to import both EventEmitter and Output:

{% code-tabs %} {% code-tabs-item title="src/app/todo-item/todo-item.component.ts" %}

import { Component, OnInit, Input, EventEmitter, Output } from '@angular/core';

{% endcode-tabs-item %} {% endcode-tabs %}

Add a method to the ItemComponent class to actually emit the event. This method will be called when the user clicks the "remove" button:

removeItem() {
  this.remove.emit(this.item);
}

Remove the todo item

Now that each todo item can emit its own removal, let's make sure that the list manager actually removes that same item from the list. For that, we'll work on the file list-manager.component.ts.

We need to respond to the remove event. Let's add it to the template, inside the <todo-item> tag:

{% code-tabs %} {% code-tabs-item title="src/app/list-manager/list-manager.component.ts" %}

<app-todo-item [item]="todoItem"
               (remove)="removeItem($event)"></app-todo-item>

{% endcode-tabs-item %} {% endcode-tabs %}

Now we just need to add the method removeItem() to the ListManagerComponent class, and use the todoListService 's method deleteItem which will remove the item from the list and update the local storage:

{% code-tabs %} {% code-tabs-item title="src/app/list-manager/list-manager.component.ts" %}

removeItem(item) {
  this.todoListService.deleteItem(item);
}

{% endcode-tabs-item %} {% endcode-tabs %}