title: IndexSizeError: Failed to execute 'arc' on 'CanvasRenderingContext2D': The radius provided (-0.5) is negative
body: <p>I am using charts from chart.js in my ionic app, i faced the following problem.
  The Chart is working pretty good once the view appears, even when navigating through tabs without writing in input. But When:</p>
  
  <p>I am in Tab1.</p>
  
  <p>I try to change Tab to Tab2 that contains Input text.</p>
  
  <p>then when the keyboard is appearing, i write or not.</p>
  
  <p>I dismiss the keyboard (That's what cause the problem)</p>
  
  <p>I go back to the Tab1</p>
  
  <p>The Chart is disappearing and not reappearing until closing the application.
  if i don't dismiss the keyboard the chart will appear
  I am not using any extra code for handling the chart
   if anyone having any crack or solution please help.</p>