angular - NativeScript Angular 6 双向绑定(bind)在 TextField 上不起作用

Question

简介

NativeScript 版本 4.2.4

Angular 版本 6.0

这是我在 nativescript 上的第一个应用程序。我熟悉 Angular，因此我需要选择 nativescript 而不是 ionic 来构建原生混合应用程序。

场景

我使用 sidekick 创建了这个应用程序。现在，首先我创建了两个 TextField 并将它们的文本与一些字符串属性绑定(bind)。在这里我告诉大家，这个模板默认使用延迟加载，这个应用程序中的所有组件都有单独的 module.ts 文件。

问题

当我在智能手机上运行应用程序(实时同步)时绑定(bind)后。双向数据绑定(bind)不起作用。我在这里分享我的代码。

app.module.ts

import { NgModule, NO_ERRORS_SCHEMA } from "@angular/core";
import { NativeScriptModule } from "nativescript-angular/nativescript.module";
import { NativeScriptUISideDrawerModule } from "nativescript-ui-sidedrawer/angular";
import { NativeScriptFormsModule } from "nativescript-angular/forms";

import { AppRoutingModule } from "./app-routing.module";
import { AppComponent } from "./app.component";

@NgModule({
    bootstrap: [
        AppComponent
    ],
    imports: [
        AppRoutingModule,
        NativeScriptModule,
        NativeScriptFormsModule,
        NativeScriptUISideDrawerModule
    ],
    declarations: [
        AppComponent
    ],
    schemas: [
        NO_ERRORS_SCHEMA
    ]
})
export class AppModule { }

home.module.ts

import { NgModule, NO_ERRORS_SCHEMA } from "@angular/core";
import { NativeScriptCommonModule } from "nativescript-angular/common";
import { NativeScriptFormsModule } from "nativescript-angular/forms";

import { HomeRoutingModule } from "./home-routing.module";
import { HomeComponent } from "./home.component";

@NgModule({
    imports: [
        NativeScriptCommonModule,
        NativeScriptFormsModule,
        HomeRoutingModule
    ],
    declarations: [
        HomeComponent
    ],
    schemas: [
        NO_ERRORS_SCHEMA
    ]
})
export class HomeModule { }

home.component.ts

import { Component, OnInit } from "@angular/core";
import { RadSideDrawer } from "nativescript-ui-sidedrawer";
import * as app from "tns-core-modules/application";

@Component({
    selector: "Home",
    moduleId: module.id,
    templateUrl: "./home.component.html"
})
export class HomeComponent implements OnInit {
    TestingText: string;
    constructor() {
        this.TestingText = 'anything';
        // Use the component constructor to inject providers.
    }

    ngOnInit(): void {

        // Init your component properties here.
    }

    onDrawerButtonTap(): void {
        const sideDrawer = <RadSideDrawer>app.getRootView();
        sideDrawer.showDrawer();
    }
}

home.component.html

<ActionBar class="action-bar">
    <!-- 
    Use the NavigationButton as a side-drawer button in Android
    because ActionItems are shown on the right side of the ActionBar
    -->
    <NavigationButton ios:visibility="collapsed" icon="res://menu" (tap)="onDrawerButtonTap()"></NavigationButton>
    <!-- 
    Use the ActionItem for IOS with position set to left. Using the
    NavigationButton as a side-drawer button in iOS is not possible,
    because its function is to always navigate back in the application.
    -->
    <ActionItem icon="res://navigation/menu" android:visibility="collapsed" (tap)="onDrawerButtonTap()" ios.position="left">
    </ActionItem>
    <Label class="action-bar-title" text="Home"></Label>
</ActionBar>

<FlexboxLayout class="page">
    <StackLayout class="form">
        <StackLayout class="input-field">
            <TextField hint="Type Something" [(ngModel)]="TestingText" secure="false" class="input input-border"></TextField>
            <StackLayout class="hr-light"></StackLayout>
        </StackLayout>

        <StackLayout class="input-field">
            <TextField hint="Binding" Text="{{TestingText}}" secure="false" class="input input-border"></TextField>
            <StackLayout class="hr-light"></StackLayout>
        </StackLayout>
    </StackLayout>
</FlexboxLayout>

此外，我还发现了以下相关问题

Binding doesnt work on textfield

但这对我来说不起作用。我认为我的问题是相同的，但在技术上有所不同。这个问题基于 Angular 2，但在我的例子中，我使用的是 Angular 6。

输出

Answer 1

您需要使用 [(ngModel)] 将其绑定(bind)到另一个文本字段

<TextField [(ngModel)]="TestingText"></TextField>

或[text]将其绑定(bind)到标签

<Label [text]="TestingText"></Label>