message: fixed error message when I click Tabbar.
diff: @@ -45,7 +45,7 @@ export default class TabBar extends React.Component {
  buttonsMargin: 5
  };
  handleClick(tab, index) {
  - if (tab !== this.state.selectedTab.tab) {
  + if (tab !== this.state.activeTab.tab) {
  this.setState({
  activeTab: { tab, index }
  });
  