How to use

Item

in

react-navigation-header-buttons

createStackNavigator({
  T1s: {
    screen:T1,
    navigationOptions: {
      headerTitle: 'T1',
      headerRight: 
      <HeaderButtons HeaderButtonComponent={NavRightBtn}>
        <Item title='title' iconName='md-cloud' onPress={()=>{console.log('you pressed here')}} />
      </HeaderButtons>
    }
  },
  T2s: T2
}, {
  defaultNavigationOptions:{
    headerStyle:{
      backgroundColor: '#456'
    },
    headerTintColor: '#678',
    title: 'T2'
  }
})