[Angular 2] Build a select dropdown with *ngFor in Angular 2
We want the start-pipe more flexable to get param, so when using it, we pass a second param as status:
<li *ngFor="#todo of todoService.todos | started : 'started'">
It will be handled as a second param which is an array of the transform() function:
transform(todos, [status]){ return todos.filter( (todoModel) => { // Only showing the todo starts with 'e' return todoModel.status === status; } ) }
So No we will only pipe 'started' status. We need a selector to handle the status:
import {Component, EventEmitter, Output} from 'angular2/core'; @Component({ selector: "status-selector", template: ` <div> <select #sel (change)="selectedStatus.emit(sel.value)"> <option *ngFor="#status of statuses"> {{status}} </option> </select> </div> ` }) export class StatusSelector{ @Output() selectedStatus = new EventEmitter(); statuses = ["started", "completed"]; ngOnInit(){ this.selectedStatus.emit(this.statuses[0]); } }
And pass the output to the list:
template: ` <todo-input></todo-input> <status-selector (selectedStatus)="status=$event"></status-selector> <todo-list [status]="status"></todo-list> `
Then in the list, we use that selected status:
<li *ngFor="#todo of todoService.todos | started : status">
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