按回车键将焦点移到下一个控件

Question

我在Angular 1.x上发现了一些项目，用户可以通过按Enter键将焦点移到下一个控件上。

'use strict';
app.directive('setTabEnter', function () {

    var includeTags = ['INPUT', 'SELECT'];

    function link(scope, element, attrs) {
        element.on('keydown', function (e) {
            if (e.keyCode == 13 && includeTags.indexOf(e.target.tagName) != -1) {
                var focusable = element[0].querySelectorAll('input,select,button,textarea');
                var currentIndex = Array.prototype.indexOf.call(focusable, e.target)
                var nextIndex = currentIndex == focusable.length - 1 ? 0 : currentIndex + 1;

                if (nextIndex >= 0 && nextIndex < focusable.length)
                    focusable[nextIndex].focus();

                return false;
            }
        });
    }

    return {
        restrict: 'A',
        link: link
    };
});

但这对Angular 2不起作用。我如何在Ingular 2中设置对下一个控件的焦点？

Answer 1

import { Directive, ElementRef, HostListener, Input, Renderer } from '@angular/core';
@Directive({
    selector: '[onReturn]'
})
export class OnReturnDirective {    
    private el: ElementRef;   
    @Input() onReturn: string;
    constructor(private _el: ElementRef,public renderer: Renderer) {
        this.el = this._el;
    }  
    @HostListener('keydown', ['$event']) onKeyDown(e:any) {
        if ((e.which == 13 || e.keyCode == 13)) {
            e.preventDefault();
            let control:any;
            control = e.srcElement.nextElementSibling;
            while (true){                
                if (control) {
                  if ((!control.hidden) && 
                     (control.nodeName == 'INPUT' || 
                      control.nodeName == 'SELECT' || 
                      control.nodeName == 'BUTTON' || 
                      control.nodeName == 'TEXTAREA'))
                     {
                            control.focus();
                            return;
                        }else{
                            control = control.nextElementSibling;
                        }                         
                }
                else {
                    console.log('close keyboard');
                    return;
                }            
            }
        }
    } 
}