我有一个代码,如下所示。这里的问题是async
ngIf
无效。即*ngIf="budgetGroups$ | async; let bg;else loading"
。我有一个可观察budgetGroups$
的数据。当我删除ngIf
时,它会很好地显示数据列表。你能告诉我问题在哪里吗?也没有显示任何错误。
注意: 如果您知道其他任何方法,请与我分享。
html的
<ion-list radio-group [(ngModel)]="budgetGroup" *ngIf="budgetGroups$ | async; let bg;else loading">
<ion-item-sliding *ngFor="let b of budgetGroups$ | async | orderByBudgetGroup">
<ion-item>
<ion-label>{{b.name }}</ion-label>
<ion-radio [value]="b.id" (ionSelect)="selectedBudgetGroup(b)"></ion-radio>
</ion-item>
<ion-item-options side="right">
<button ion-button (click)="editBudgetGroup(b)" color="primary">
<ion-icon name="ios-create-outline"></ion-icon>
</button>
<button ion-button (click)="deleteBudgetGroup(b)" color="danger">
<ion-icon name="ios-trash-outline"></ion-icon>
</button>
</ion-item-options>
</ion-item-sliding>
<ion-item>
</ion-item>
</ion-list>
<ng-template #loading>
<ion-grid>
<ion-row class="header">
</ion-row>
<ion-row class="footer">
<ion-col col-12 class="font-size-14" text-center>
<div>
<P class="margin-bottom-0">No Budget Group. You can create them by </P>
<p class="margin-top-0">tapping the “+” button above</p>
</div>
</ion-col>
</ion-row>
</ion-grid>
</ng-template>
.TS
budgetGroups$: Observable<BudgetGroup[]>
ionViewDidLoad() {
this.budgetGroups$ = this.budgetGroupProvider.getAllBudgetGroups().valueChanges();
}
答案 0 :(得分:2)
问题是您使用
async
管道两次。把它取下来*ngFor
部分。
<ion-list radio-group [(ngModel)]="budgetGroup" *ngIf="budgetGroups$ | async; let bg;else loading">
<ion-item-sliding *ngFor="let b of bg | orderByBudgetGroup">
<ion-item>
<ion-label>{{b.name }}</ion-label>
<ion-radio [value]="b.id" (ionSelect)="selectedBudgetGroup(b)"></ion-radio>
</ion-item>
<ion-item-options side="right">
<button ion-button (click)="editBudgetGroup(b)" color="primary">
<ion-icon name="ios-create-outline"></ion-icon>
</button>
<button ion-button (click)="deleteBudgetGroup(b)" color="danger">
<ion-icon name="ios-trash-outline"></ion-icon>
</button>
</ion-item-options>
</ion-item-sliding>
<ion-item>
</ion-item>
</ion-list>
<ng-template #loading>
<ion-grid>
<ion-row class="header">
</ion-row>
<ion-row class="footer">
<ion-col col-12 class="font-size-14" text-center>
<div>
<P class="margin-bottom-0">No Budget Group. You can create them by </P>
<p class="margin-top-0">tapping the “+” button above</p>
</div>
</ion-col>
</ion-row>
</ion-grid>
</ng-template>