How to change content in a div dynamically via radio button control?

Question

I am trying to build a form that will intake scheduling information that can potentially come in multiple different formats (weekly, monthly, other). I was planning on having a schedule section of the form where the user selects the type of schedule via a radio button group. If the weekly option is chosen, a group of checkboxes will appear with weekdays so you can select the days of the week. if monthly, then the day of the month can be chosen, and so on. I have tried using the *ngIf way of making things appear, and it isn't working, and I'm getting no error messages. Any ideas on how to implement this?

I am using: -Angular material elements -Angular 2 (8) -Angular reactive forms

I have a portion of this implemented already, below is the code for the radio buttons and the first schedule portion I want to hide (apologies for the poor formatting of the code, still figuring out Stack Overflow):

<form [formGroup] = "SchedInfo" (ngSubmit)="onSubmit()">

<mat-radio-group formControlName= "sType" (ngSubmit)= "onSubmit()">
<mat-radio-button type="radio"  [value] ="true" [checked] = "value">Weekly</mat-radio-button>
<mat-radio-button type="radio"  [value] ="false" [checked] = "!value">Monthly</mat-radio-button>
</mat-radio-group>

<div class = "weeklyS" *ngIf= "sType.value">
<br>
<!-- possibly need to resturcture the section below -->
<mat-checkbox formControlName= "mo">Monday</mat-checkbox>
<mat-checkbox formControlName= "tu">Tuesday</mat-checkbox>
<mat-checkbox formControlName= "we">Wednesday</mat-checkbox>
<mat-checkbox formControlName= "th">Thursday</mat-checkbox>
<mat-checkbox formControlName= "fr">Friday</mat-checkbox>
<mat-checkbox formControlName= "sa">Saturday</mat-checkbox>
<mat-checkbox formControlName= "su">Sunday</mat-checkbox>
</div>

In the end, my goal for this is to have a schedule module that can be switched between several different input methods.

Also:

should I have one div that is repopulated with each change of selection, or should I have multiple divs that show/ hide depending on the selection?

Answer 1

What you actually need to do is to bind the value of your radio correctly and how to get the value back. This was the simples example I could come up with.

First our template code

<form [formGroup]="myForm" (submit)="onSubmit(myForm.value)" novalidate>
    <label id="example-radio-group-label">Pick your Type</label>
<mat-radio-group class="example-radio-group" formControlName="sType">
  <mat-radio-button class="example-radio-button" *ngFor="let sfType of scheduleTypes" [value]="sfType">
    {{sfType}}
  </mat-radio-button>
</mat-radio-group>


<ng-container [ngSwitch]="getScheduleType()">
<div  *ngSwitchCase="'Weekly'">
  Weekly Content
</div>
<div *ngSwitchCase="'Monthly'">
  Monthly Content
</div>
</ng-container>

</form>

Now the component code:

   import { Component, OnChanges, OnDestroy, OnInit, Output, ViewChild } from '@angular/core';
import { FormBuilder, FormGroup, Validators } from '@angular/forms';


export interface DataModel {
  sType: string;
}
/**
 * @title Radios with ngModel
 */
@Component({
  selector: 'radio-ng-model-example',
  templateUrl: 'radio-ng-model-example.html',
  styleUrls: ['radio-ng-model-example.css'],
})
export class RadioNgModelExample {
  myForm: FormGroup;

//List of the schedule types. You might want to change this to an ENUM
  scheduleTypes: string[] = ['Weekly', 'Monthly'];

  constructor(private formBuilder: FormBuilder) {
    this.buildForm();
  }

//Remember to build your form properly
  public buildForm() {
    this.myForm = this.formBuilder.group({
      sType: [null]
    });
  }

  public onSubmit(data: DataModel) {
    //Submit Data Here
  }

  public getScheduleType() {
    //Get the value of your stypeControl
    return this.myForm.controls['sType'].value;
  }


}

Live Example