angularfire2和ionic2。添加或删除对象时,映射数据将重新呈现整个列表
我有一个关于使用angularfire2从firebase获取数据的问题。 我的数据库体系结构如下所示:angularfire2和ionic2。添加或删除对象时,映射数据将重新呈现整个列表,angular,firebase-realtime-database,angularfire,ionic2,angularfire2,Angular,Firebase Realtime Database,Angularfire,Ionic2,Angularfire2,我有一个关于使用angularfire2从firebase获取数据的问题。 我的数据库体系结构如下所示: { "productsfavorites" : { "-KNnfAs31LkMUjU60VAG" : true }, "short_desc" : { "-KNnfAs31LkMUjU60VAG" : { "city" : "Frontignan Plage", "desc" : "Superbe maison les pieds da
{
"productsfavorites" : {
"-KNnfAs31LkMUjU60VAG" : true
},
"short_desc" : {
"-KNnfAs31LkMUjU60VAG" : {
"city" : "Frontignan Plage",
"desc" : "Superbe maison les pieds dans l'eau",
"favorite" : true,
"orientation" : "portrait",
"price" : 335000,
"ratio" : 2161,
"ratiok" : 22,
"size" : 155,
"src" : "http://decor.friesiannews.com/wp-content/uploads/2014/08/Modern-Beach-Themed-Bedrooms.jpg",
"type" : "Maison"
},
"-KNngYcNoUUql4oIMxwU" : {
"city" : "Frontignan",
"desc" : "A nice home in Frontignan",
"orientation" : "portrait",
"price" : 255000,
"ratio" : 2125,
"ratiok" : 21,
"size" : 120,
"src" : "http://homeimprov.etienneathens.com/wp-content/uploads/2014/08/The-Beach-Ornament.jpg",
"type" : "Maison"
},
}
}
在我的ts文件中,我有以下内容:
import {Page, Content} from 'ionic-angular';
import {AngularFire, FirebaseListObservable} from "angularfire2";
import { Observable } from 'rxjs';
import 'rxjs/add/operator/map';
@Page({
templateUrl: "build/pages/page1/page1.html",
})
export class Page1 {
products: Observable<any[]>;//contains the ref for the goods in a given city
constructor(private af: AngularFire) {
this.getShortDescFav();
}
//To list the favorites products I use this function:
getShortDescFav() {
this.products = this.af.database.list('/productsfavorites/')
.map((items) => {
return items.map(item => {
item.short_desc = this.af.database.object('/short_desc/' + item.$key)
return item;
});
});
}
}
import{Page,Content}来自“离子角”;
从“angularfire2”导入{AngularFire,FirebaseListObservable};
从“rxjs”导入{Observable};
导入'rxjs/add/operator/map';
@页面({
templateUrl:“build/pages/page1/page1.html”,
})
导出类第1页{
products:Observable;//包含给定城市中商品的参考号
建造师(私人af:AngularFire){
这个.getShortDescFav();
}
//要列出收藏夹产品,我使用此功能:
getShortDescFav(){
this.products=this.af.database.list(“/productsfavorites/”)
.map((项目)=>{
返回items.map(item=>{
item.short_desc=this.af.database.object('/short_desc/'+item.$key)
退货项目;
});
});
}
}
然后在html文件中我这样做
<ion-card *ngFor="let item of products | async">
<img src="{{(item.short_desc | async)?.src}}" class="lazy" alt="Image" id="{{item.$key}}" (load)="imageLoaded(item.$key)">
<ion-card-content>
<ion-card-title>
<ion-row>
<ion-col width-67 no-padding>
{{(item.short_desc | async)?.city}}
</ion-col>
<ion-col width-33 text-right no-padding>
<span primary>
{{(item.short_desc | async)?.price}}€
</span>
</ion-col>
</ion-row>
</ion-card-title>
<ion-row>
<ion-col width-33 no-padding>
{{(item.short_desc | async)?.type}}
</ion-col>
<ion-col width-33 no-padding text-center>
{{(item.short_desc | async)?.size}}m2
</ion-col>
<ion-col width-33 no-padding text-right>
{{(item.short_desc | async)?.ratiok}}K€/m2
</ion-col>
</ion-row>
<p>
{{(item.short_desc | async)?.desc}}
</p>
<ion-row>
<ion-col width-25 text-center>
<ion-icon name="md-eye"center></ion-icon>
</ion-col>
<ion-col width-25 text-center>
<ion-icon name="md-share"></ion-icon>
</ion-col>
<ion-col width-25 text-center>
<ion-icon name="md-create"></ion-icon>
</ion-col>
<ion-col width-25 text-center>
<ion-icon *ngIf="(item.short_desc | async)?.favorite != true" name="md-star" (click)="favorite(item.$key)" class="regular-product"></ion-icon>
<ion-icon *ngIf="(item.short_desc | async)?.favorite == true" name="md-star" (click)="regular(item.$key)" class="favorite-product"></ion-icon>
</ion-col>
</ion-row>
</ion-card-content>
</ion-card>
{{(item.short_desc|async)?.city}
{{(item.short|u desc | async)?.price}
{{(item.short_desc | async)?.type}
{{(item.short_desc | async)?.size}m2
{{(item.short_desc | async)?.ratiok}K欧元/m2
{{(item.short_desc|async)?.desc}
将显示产品标记为收藏夹,但一旦新产品成为收藏夹,列表将重新呈现。
如何防止列表被重新呈现,并且只为新产品添加一张卡片作为收藏夹
希望有人能在这方面帮助我
亚历克斯。取而代之的是这个
item.short_desc = this.af.database.object('/short_desc/' + item.$key)
return item;
});
这样做
return this.af.database.object('/short_desc/' + item.$key);
同样在html中,您将获得item而不是item.short\u desc