title: Echart.js charts isn't showing tooltip
body: <p>I am using Echart.js library.</p>
  
  <p>var echartLine = echarts.init(document.getElementById('myChart'), theme);</p>
  
  <p>In echart option I add :</p>
  
  <pre><code>tooltip: {
                      show: true,
                      showContent: true,
                      alwaysShowContent: true,
                      triggerOn: 'mousemove',
                      trigger: 'axis',
                      axisPointer:
                          {
                              label: {
                                  show: true,
                              }
                          }
  
                  }, 
  </code></pre>
  
  <p>Tooltip don't appear. Image is bellow. 
  <a href="https://i.stack.imgur.com/1Np2c.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1Np2c.png" alt="enter image description here"></a></p>