Angular Nativescript 可见性默认为 true，即使变量已初始化 [英] Angular Nativescript visibility defaults to true, even when variable is initialized

问题描述

有没有办法在 Nativescript 中默认隐藏"一个元素?

Is there a way to default "hide" an element in Nativescript?

我的组件中有

export class HouseholdContactComponent{
  private isLoading = true
}

在我的 xml 中

<StackLayout [visibility]="isLoading ? 'collapse' : 'visible'">
  <Label text="Hi there"></Label>
</StackLayout>

使用此代码，屏幕会闪烁您好"消息，然后消失.

With this code, the screen flashes the "Hi there" message and then it goes away.

推荐答案

与其使用 [visibility] 属性，不如使用 Angular *ngIf 指令.

Rather than using the [visibility] property, you should use the Angular *ngIf directive.

<StackLayout *ngIf="!isLoading">
    <Label text="Hi there"></Label>
</StackLayout>

附带说明，为了绑定到一个属性属性并将其绑定到 Angular 正在做的插值，您需要在它前面加上 attr，例如您需要编写 [attr.visibility] 而不仅仅是 [visibility].

On a side note, in order to bind to a attribute property and bind it to interpolation Angular is doing you need to prefix it with attr, for example you would need to write [attr.visibility] rather than just [visibility].

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