LegendLabelsCallback (Charba - J2CL and GWT charts library based on CHART.JS)

```
public interface LegendLabelsCallback
```
Generates legend items for each thing in the legend.

Author:

Andrea "Stock" Stocchero

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`List<LegendLabelItem>`	`generateLegendLabels(IsChart chart, List<LegendLabelItem> defaultLabels)`	Generates legend items for each thing in the legend.

- Method Detail
  - generateLegendLabels
```
List<LegendLabelItem> generateLegendLabels(IsChart chart,
                                           List<LegendLabelItem> defaultLabels)
```
    Generates legend items for each thing in the legend. Default implementation returns the text + styling for the color box.
    
    Parameters:
    
    chart - chart instance
    
    defaultLabels - list of labels created by CHART.JS using the out of the box generate labels callback.
    
    Returns:
    
    a list of legend items. if null, uses the default implementation