import { VantComponent } from '../common/component'; VantComponent({ relation: { name: 'badge', type: 'descendant', linked(target) { this.badges.push(target); this.setActive(this.data.active); }, unlinked(target) { this.badges = this.badges.filter(item => item !== target); this.setActive(this.data.active); } }, props: { active: { type: Number, value: 0, observer: 'setActive' } }, beforeCreate() { this.badges = []; this.currentActive = -1; }, methods: { setActive(active) { const { badges, currentActive } = this; if (!badges.length) { return Promise.resolve(); } this.currentActive = active; const stack = []; if (currentActive !== active && badges[currentActive]) { stack.push(badges[currentActive].setActive(false)); } if (badges[active]) { stack.push(badges[active].setActive(true)); } return Promise.all(stack); } } });