Angular Material v6 Mat-Footer - “Cannot read property 'template' of undefined”

19
votes

I'm trying to implement a footer row into a mat-table component after recently upgrading to angular 6 for this purpose, but after adding both the mat-footer-cell and mat-footer-row elements in the table, I get the following error:

ERROR TypeError: Cannot read property 'template' of undefined at MatFooterRowDef.push../node_modules/@angular/cdk/esm5/table.es5.js.CdkFooterRowDef.extractCellTemplate (vendor.js:17400)

The table still appears on the page, but with no data, no footer row, and a T symbol where to the right of each column heading.

HTML:

  <ng-container matColumnDef="total">

    <mat-header-cell *matHeaderCellDef mat-sort-header style="width: 15%; flex: none">Total</mat-header-cell>

    <mat-cell *matCellDef="let item" style="width: 15%; flex: none">{{item.total | currency: 'GBP'}}</mat-cell>

    <td mat-footer-cell *matFooterCellDef>100</td>

  </ng-container>

  <mat-header-row *matHeaderRowDef="tableColumns"></mat-header-row>

  <mat-row *matRowDef="let row; columns: tableColumns" (click)="editItem(row)"></mat-row>

  <tr mat-footer-row *matFooterRowDef="tableColumns"></tr>

</mat-table>
3
angularangular-materialangular6
does the table display normally without the mat-footer-row? – Michael Doye
Yes, no problems until I added the footer elements – nick.cook
Are you perhaps able to recreate this error in a stackblitz? stackblitz.com/angular/klengxeqvdd – Michael Doye
Amazing @MichaelDoye Your Example was the solution for me. – Rahul Sonwanshi

3 Answers

60
votes

FIXED: This was not made clear in the material documentation, but all columns must contain a <mat-footer-cell/> element, even if only one column will contain content.

9
votes

You can define your own "tableFooterColumns" variable.

tableFooterColumns: string[] = ['total'];

and use it in the template (change "colspan" for your needs):

 <tr mat-footer-row *matFooterRowDef="tableFooterColumns" colspan="2"></tr>
5
votes

Need to include mat-footer-cell for each column:

<div class="example-container mat-elevation-z8">
  <mat-table #table [dataSource]="dataSource">

    <mat-header-row *matHeaderRowDef="displayedColumns; sticky: true"></mat-header-row>
    <mat-row *matRowDef="let row; columns: displayedColumns;"></mat-row>

    <ng-container matColumnDef="categoryName">
      <mat-header-cell *matHeaderCellDef> First Name </mat-header-cell>
      <mat-cell *matCellDef="let row"> {{row.firstName}} </mat-cell>
      
      //This is the part for which the code is breaking
      <mat-footer-cell *matFooterCellDef> Your footer column Name will goes here </mat-footer-cell>**
    </ng-container>
    <ng-container matColumnDef="categoryName">
      <mat-header-cell *matHeaderCellDef> Last Name </mat-header-cell>
      <mat-cell *matCellDef="let row"> {{row.lastName}} </mat-cell>
      
      //This need to be included in all your columns
      <mat-footer-cell *matFooterCellDef> Your 2nd footer column Name will goes here </mat-footer-cell>**
    </ng-container>
    <mat-footer-row *matFooterRowDef="displayedColumns; sticky: true"></mat-footer-row>
  </mat-table>
</div>