title: Show hidden textbox with Polymer after button press
body: <p>I have the following code</p>
  
  <pre><code>&lt;dom-module id="practice-list"&gt;
      &lt;template&gt;
          &lt;paper-drawer-panel&gt;
              &lt;paper-header-panel main mode="waterfall-tall"&gt;
                  &lt;paper-toolbar id="mainToolbar"&gt;
                      &lt;paper-icon-button id="paperToggle" icon="menu" paper-drawer-toggle&gt;&lt;/paper-icon-button&gt;
                      &lt;span class="flex"&gt;&lt;/span&gt;
                      &lt;paper-icon-button icon="search" on-tap="srchandler" id="srchandler"&gt;&lt;/paper-icon-button&gt;
                      &lt;input type="text" id="searchText" show$="{{show}}" /&gt;
                      &lt;div class="middle paper-font-display2 app-name ident"&gt;Practice List&lt;/div&gt;
                  &lt;/paper-toolbar&gt;
              &lt;/paper-header-panel&gt;
          &lt;/paper-drawer-panel&gt;
      &lt;/template&gt;
  
      &lt;script&gt;
          Polymer({
              is: "practice-list",
              show: {
                  type: Boolean,
                  value: false
              },
              ready: function () {
              },
              srchandler: function () {
                  this.show = !this.show;
                  alert('Is it showing?');
              }
          });
      &lt;/script&gt;
  &lt;/dom-module&gt;
  </code></pre>
  
  <p>Which in turn uses the following css</p>
  
  <pre><code>#searchText
  {
      width:0px;
      border: none;
      line-height:30px;
      border-radius:5px;
  
      background:#3F59B5;
      color:#fff;
  
      outline: 0;
  
      visibility: hidden;
  
  }
  
  #searchText[show] input {
      padding: 10px;
      visibility: visible;
      width:200px;
  
  }
  </code></pre>
  
  <p>Now I was trying to use the technique described here, but to no avail.</p>
  
  <p><a href="https://stackoverflow.com/questions/29463855/polymer-search-input-text-from-icon">polymer search input text from icon</a></p>
  
  <p>Even though I know the handler for the on-tap of the paper-icon-button is working and called the textbox does not appear.</p>