title: How can I render mat-table by button I defined?
body: <p>I have mat-table and select button above mat-table. Once I click select butotn, I am pulling datas from web API and I want data to be viewed in table. But clever!! Angular team does not support this or not documented.  Very classical things are not supported in angular-Material components. </p>
  
  <p>Let me ask question: </p>
  
  <p><strong>.html</strong></p>
  
  <pre><code>&lt;button class="btn btn-primary"
              (click)="list()"&gt;
            Select
  &lt;/button&gt;
  
  
  &lt;mat-table [dataSource]="dataSource1" class="mat-elevation-z8"&gt;
  ......
  &lt;/mat-table&gt;
  </code></pre>
  
  <p><strong>.ts</strong></p>
  
  <pre><code>list() {
  
      dataSource1 = .....
  
  }
  </code></pre>
  
  <p>How can I provide this ?  Table is not rendered after datas are successfully assigned to dataSource1 in list() method. What should I do to rerender </p>