title: Which of the following two codes is better in terms of execution efficiency?
body: <p>May I ask which of the following two codes is better in terms of execution efficiency? Which one is recommended?</p>
  <pre class="lang-dart prettyprint-override"><code> Widget buildItem(){
  
      final List&lt;Widget&gt; items = [];
  
      if(this.widget.showItem1){
        items.add(Row(children: &lt;Widget&gt;[
          Container(),
          Container(),
        ]));
      }
  
      if(this.widget.showItem2){
        items.add(Row(children: &lt;Widget&gt;[
          Container(),
          Container(),
        ]));
      }
  
      if(this.widget.showItem3){
        items.add(Row(children: &lt;Widget&gt;[
          Container(),
          Container(),
        ]));
      }
  
      return Column(children: items);
    }
  </code></pre>
  <pre class="lang-dart prettyprint-override"><code>Widget buildItem(){
      return Column(children: &lt;Widget&gt;[
        this.widget.showItem1 ?  Row(children: &lt;Widget&gt;[Container(), Container(),]): Container(),
        this.widget.showItem2 ?  Row(children: &lt;Widget&gt;[Container(), Container(),]): Container(),
        this.widget.showItem3 ?  Row(children: &lt;Widget&gt;[Container(), Container(),]): Container(),
      ],);
    }
  </code></pre>