My [(ngModel)] is not working in the custom component in Ionic 4

问题

I am working in my Ionic 4 project and I have created a custom component but in that custom component my [(ngModel)] is not working.

This is my custom-header-component.component.html:

<ion-select [(ngModel)]="languageSelected" (ionChange)='setLanguage()' ngDefaultControl>
    <ion-select-option value="en">English</ion-select-option>
    <ion-select-option value="ar">Arabic</ion-select-option>
</ion-select>

In this html my [(ngModel)] is not working because it is not printing any value in the console.

This is my custom-header-component.component.ts:

languageSelected: any;
setLanguage() {
let me=this;
console.log('languageSelected',me.languageSelected);
}

In this ts file, it is not printing any value.

Maybe the problem is that, I have not included the FormsModule.

This is my Folder:

custom-header-component:
|
-- custom-header-component.component.html
-- custom-header-component.component.scss
-- custom-header-component.component.spec.ts
-- custom-header-component.component.ts

components.module.ts

This is my components.module.ts:

import { NgModule, CUSTOM_ELEMENTS_SCHEMA } from '@angular/core';
import { CustomHeaderComponentComponent } from './custom-header-component/custom-header-component.component';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';

@NgModule({
    declarations: [CustomHeaderComponentComponent],
    exports: [CustomHeaderComponentComponent],
    schemas: [CUSTOM_ELEMENTS_SCHEMA],
    imports: [
     FormsModule,
     ReactiveFormsModule
    ],
})
export class ComponentsModule{}

Any help is much appreciated.

回答1:

It should be <ion-option

 <ion-option value="en">English</ion-option>

STACKBLITZ DEMO

EDIT:

If it's ionic 4 ,your code looks correct. As mentioned in the question if you have not included FormsModule you need to add it as

import { ReactiveFormsModule } from '@angular/forms';

@NgModule({
  declarations: [AppComponent],
  entryComponents: [],
  imports: [
    BrowserModule, 
    IonicModule.forRoot(), 
    AppRoutingModule,
    ReactiveFormsModule
  ],
  providers: [
    StatusBar,
    SplashScreen,
    { provide: RouteReuseStrategy, useClass: IonicRouteStrategy }
  ],
  bootstrap: [AppComponent]
})
export class AppModule {}

回答2:

you just need to import FormsModule in app.module.ts

import { FormsModule } from '@angular/forms';

and add ComponentPage inside declarations and entryComponents

You can see the example below

In app.module.ts

import { FormsModule } from '@angular/forms';

import { ComponentPage } from './component/component.page'


@NgModule({
  declarations: [
  ComponentPage,
 ],
entryComponents: [
   ComponentPage,
  ],
  imports: [FormsModule],

})

回答3:

Try This:

<ion-select ngDefaultControl [(ngModel)]="languageSelected" (ionChange)='setLanguage($event)'>
    <ion-select-option value='en' [selected]="language==='en' ? true : null">English</ion-select-option>
    <ion-select-option value='ar' [selected]="language==='ar' ? true : null">Arabic</ion-select-option>
</ion-select> 

 setLanguage($event) {
    let me=this;
   console.log('Default language:', $event.target.value);
  }

In this, You can get the selected value.

来源：https://stackoverflow.com/questions/55683500/my-ngmodel-is-not-working-in-the-custom-component-in-ionic-4

标签

angular

ionic-framework