Trying To Render A "loading" Prompt But Then The Data Once Its Ready

I have MyFunction() that populates a data source for my render's listView, and the process works on a local database and starts in the constructor of the screen. Constructor: cons

Solution 1:

At first, you don't need Data in state, as you don't use it at all.

To solve your problem you can use such constructor:

constructor(props) {
  super(props);
  
  getDataFromServer().then((response) => {
    letDataSource = newListView.DataSource({
      rowHasChanged: (r1, r2) => r1 !== r2
    });
    
    this.setState({
      IsLoading: false,
      DataSource: DataSource.cloneWithRows(response)
    });
  });

  this.state = {
    IsLoading: true
  };
}