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.
First, we need to add the button to the item, so we'll work on the file
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):
src/app/item/item.component.tstemplate: `<div class="todo-item">{{ todoItem.title }}β<button class="btn btn-red" (click)="removeItem()">remove</button></div>`,
Add a new output to the ItemComponent
class, which will be emitted to the list manager when a user presses its remove button:
src/app/item/item.component.ts@Output() remove:EventEmitter<any> = new EventEmitter();
Make sure to import both EventEmitter
and Output
:
src/app/item/item.component.tsimport { Component, OnInit, Input, EventEmitter, Output } from '@angular/core';
Add a method to the ItemComponent
class to actually emit the event. This method will be called when the user clicks the "remove" button:
src/app/item/item.component.tsremoveItem() {this.remove.emit(this.todoItem);}
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:
src/app/list-manager/list-manager.component.ts<todo-item [todoItem]="item" (remove)="removeItem($event)"></todo-item>
Now we just need to add the method removeItem()
to the ListManagerComponent
class:
src/app/list-manager/list-manager.component.tsremoveItem(item) {this.todoList = this.todoListService.removeItem(item);}
Removing the item is handled in the service. Open todo-list.service.ts and add a method called
removeItem
to the TodoListService
class:
src/app/todo-list.service.tsremoveItem(item) {return this.storage.destroy(item);}
This method calls the destroy
method we already created in todo-list-storage.service.ts earlier.