Catching loading event

Hello,
I want to make a spinner indicating data being refreshed. But how can I catch event for data being loaded?

Im getting data this way:
```
this.source = new ServerDataSource(http, { endPoint: 'https://jsonplaceholder.typicode.com/photos' });
```

I tried to user LocalDataSource, and manually getting data on "onSearch":
```
getData(modifiedData?) {
this.loading = true;
let sourceCopy = modifiedData ? modifiedData : this.source;
let requestData = {
filter: sourceCopy.getFilter(),
paging: sourceCopy.getPaging(),
sort: sourceCopy.getSort()
}
this.service.getData(requestData).then((data) => {
this.source.load(data);
this.loading = false;
});
}
```
This works for search input, but this way I'd have to write pagination component on my own, while the stock one is just fine.

Any ideas?