title: Disable/Enable selection based on row content of PrimeNG TurboTable or TreeTable
body: <p>With p-treeTable i can enable selection for all rows, based on selectionMode = "single". Now i'd like to disable selection for rows, which are not intended to be selected.</p>
  
  <p>PrimeNG 7, Angular 7.</p>
  
  <p>If I remove <code>[ttRow]="rowNode" [ttSelectableRow]="rowNode"</code> of tr's body template, all rows are not selectable.</p>
  
  <pre><code>&lt;p-treeTable [value]="nodes" [columns]="columns" selectionMode="single" 
  [(selection)]="selectedNode" dataKey="id" &gt;
  
  ...
  
     &lt;ng-template pTemplate="body" let-rowNode let-rowData="rowData" let-columns="columns"&gt;
        &lt;tr [ttRow]="rowNode" [ttSelectableRow]="rowNode"&gt;
          &lt;td *ngFor="let col of columns"&gt;            
            {{ rowData[col.field] }}
          &lt;/td&gt;
        &lt;/tr&gt;
      &lt;/ng-template&gt;
    &lt;/p-treeTable&gt;
  </code></pre>
  
  <p>Now i need a check based on the row data, e.g. <code>rowData.selectable', to enable/disable row selection based on the outcome of</code>rowData.selectable`.
  Any ideas how to achieve this?</p>