Accessing Input fields inside Angular Material table

Question

I've been trying for days to get data from input fields inside an Angular Material Table.

I am basically populating a table with values that come from an API, however whenever we don't get any date, in my case a course doesn't have a scheduled date set, i am inserting a text box where the value should be displayed so the user can set a date for that specific course.

Like this: Note: Sorry for the censoring, work related names had to be removed.

This is my html code:

<mat-card>
    <form  #traineeForm="ngForm">
      <mat-form-field>
        <input  readonly matInput type="text" name="name" [ngModel] = "trainee.name"  #name="ngModel">
      </mat-form-field>
      <mat-form-field>
        <input readonly matInput email type="text"  name="email" [ngModel] = "trainee.email" #email="ngModel">
      </mat-form-field>
      <mat-form-field>
        <input readonly matInput type="text"  name="type" [ngModel] = "trainee.type" #type="ngModel">
      </mat-form-field>
      <button mat-raised-button color ="primary" type ="submit">Edit</button>
      <button mat-raised-button color ="warn" type ="submit" (click)="onDelete(trainee.id)">Delete</button>
    </form>
  </mat-card>
<br>
  <mat-card>
    
      <table mat-table [dataSource]="courses" class="mat-elevation-z8">
      
      <ng-container matColumnDef="courseOrderID">
        <th mat-header-cell *matHeaderCellDef>Course Order ID</th>
        <td mat-cell *matCellDef="let element"> {{element.courseOrderID}}</td>
      </ng-container>
      
       <ng-container matColumnDef="title">
          <th mat-header-cell *matHeaderCellDef>Course Title </th>
          <td mat-cell *matCellDef="let element"> {{element.title}}</td>
      </ng-container>
      <ng-container matColumnDef="description">
          <th mat-header-cell *matHeaderCellDef>Course Description </th>
          <td mat-cell *matCellDef="let element"> {{element.description}}</td>
       </ng-container>
      <ng-container matColumnDef="duration">
          <th mat-header-cell *matHeaderCellDef>Duration </th>
          <td mat-cell *matCellDef="let element"> {{element.duration}}</td>
      </ng-container>
      <ng-container matColumnDef="scheduledDate">
        <th mat-header-cell *matHeaderCellDef>Scheduled Date </th>
      <td mat-cell *matCellDef="let element">
         <mat-form-field>
              <input matInput [matDatepicker]="picker" placeholder="Choose a date">
              <mat-datepicker-toggle matSuffix [for]="picker"></mat-datepicker-toggle>
              <mat-datepicker #picker></mat-datepicker>
          </mat-form-field>
         {{element.scheduledDate}}</td>
      </ng-container>
      <ng-container matColumnDef="trainer">
          <th mat-header-cell *matHeaderCellDef>Trainer </th>
          <td mat-cell *matCellDef="let element">
              <mat-form-field><input matInput color="warn" *ngIf="!element.trainer"></mat-form-field> {{element.trainer}}</td>
      </ng-container>
      <ng-container matColumnDef="save">
          <th mat-header-cell *matHeaderCellDef></th>
          <td mat-cell *matCellDef="let element">
              <button mat-raised-button color ="primary" type ="submit" (click)="onSaveAssignment(trainee, element, picker)">Save</button></td>
      </ng-container>
      <tr mat-header-row *matHeaderRowDef="coursesdisplayColumns">
      </tr>
      <tr mat-row *matRowDef="let courses; columns: coursesdisplayColumns"></tr>
      </table>
      <br>
 
      </mat-card>

And this is my TypeScript code:

import { Trainee } from '../trainees.model';
import { Component, OnInit, OnDestroy } from '@angular/core';
import { Subscription } from 'rxjs';
import { TraineesService } from '../../trainees.service';
import { ActivatedRoute, ParamMap } from '@angular/router';
import { Course } from '../../courses/courses.model';
import { CoursesService } from '../../courses.service';
import { Assignment } from '../../assignments/assignments.model';
import { NgForm } from '@angular/forms';

@Component({
  selector: 'app-trainee-details',
  templateUrl: './trainee-details.component.html',
  styleUrls: ['./trainee-details.component.css']
})


export class TraineeDetailsComponent implements OnInit, OnDestroy {
  
  private traineeId: string;
  trainee: Trainee;
  assignment: Assignment;
  courses: Course[] = [];
  coursesdisplayColumns = ['courseOrderID', 'title','description','duration','scheduledDate','trainer','save'];
  
  constructor(public traineeService: TraineesService, public route: ActivatedRoute, public coursesService: CoursesService){}

  ngOnInit() {
    this.route.paramMap.subscribe((paramMap: ParamMap) => {
      if(paramMap.has('traineeId')){
        this.traineeId = paramMap.get('traineeId');
        this.trainee = this.traineeService.getTrainee(this.traineeId);
      }
    });
    this.coursesService.getCoursesByJob(this.trainee.job);
    this.coursesService.getCoursesUpdateListener().subscribe((courses: Course[]) =>{
      this.courses = courses;
    });
  }

  onDelete(traineeId: string)
  {
    this.traineeService.deleteTrainee(traineeId);
  }
  onSaveAssignment(trainee: Trainee, selectedCourse: Course, dateForm: Date){
  
    console.log(trainee.id);
    console.log(selectedCourse.description);
    console.log(dateForm);
  }
  ngOnDestroy() {

  }
}

When i call onSaveAssignment(), the trainee ID and course ID are getting logged in the console correctly as those are defined in typescript, but I have no ideea how should i bring that date selected in the interface, i tried with ng-model but it did not work and I had to define a form for each input and still did not work.

Is there any way to get that values from inputs on each row when the Save button is pressed ?

Or if i put 1 button for all of them is there any way to do a foreach on every input value in the interface ?

Answer 1

You can get the values with ngModel by creating an object containing all values using the index as attribute.

In you component, put an object:

public myDates : any = {};

Then use ngModel with the index for your input date:

<ng-container matColumnDef="scheduledDate">
  <th mat-header-cell *matHeaderCellDef>Scheduled Date </th>
  <td mat-cell *matCellDef="let element; let i = index">
    <mat-form-field>
      <input matInput [(ngModel)]="myDates[i]" [matDatepicker]="picker" placeholder="Choose a date">
      <mat-datepicker-toggle matSuffix [for]="picker"></mat-datepicker-toggle>
      <mat-datepicker #picker></mat-datepicker>
    </mat-form-field>
  </td>
</ng-container>

For each row, it will add an attribute to the object myDates. Using index permits to guarantee uniqueness. Your object will look like: {1: date1, 2: date2 ...}.

Then you can get the value by knowing the index of the row. You can get it directly when clicking on the button:

<ng-container matColumnDef="save">
  <th mat-header-cell *matHeaderCellDef></th>
  <td mat-cell *matCellDef="let element; let i = index">
    <button mat-raised-button color ="primary" type ="submit" (click)="onSaveAssignment(trainee, element, myDates[i])">Save</button>
  </td>
</ng-container>