Uncaught TypeError: Cannot read property 'hideCompleted' of null

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1 
<label className="hide-completed">
            <input
              type="checkbox"
              readOnly
              checked={this.state.hideCompleted}
              onClick={this.toggleHideCompleted.bind(this)}
            />
            Hide Completed Tasks
          </label>

While adding this part in the tutorial project it shows

  • Uncaught TypeError: Cannot read property ‘hideCompleted’ of null
  • modules.js?hash=62336618ea1e30aa827e267769667ce41bc2fbc9:13456 The above error occurred in the component:
    in App (created by ReactMeteorDataComponent)
    in ReactMeteorDataComponent
  • modules.js?hash=62336618ea1e30aa827e267769667ce41bc2fbc9:14703 Uncaught TypeError: Cannot read property ‘hideCompleted’ of null
    at App.render (App.js:38)