setstate

```
setState() 
- is Asynchronous
- can have a function as a parameter instead of object
- can accepts a Callback function as a second argument (optional)
- does not return promise
```

function updateState(){
  this.setState({load: true}, () => {
     console.log(this.state);
  })
}

function getData(state){
  return new Promise((resolve, reject) => {
      this.setState(state, resolve);
  })    
}

async function updateState(){
    await this.setStateAsync({ load: true });
}