Plugin (Charba, GWT wrapper for CHART.JS)

All Known Implementing Classes:

AbstractPlugin, ChartBackgroundColor, ChartPointer, ColorSchemes, DatasetsItemsSelector
```
public interface Plugin
```
This interface is defining the extension hook for Chart.JS plugin implementation (both for inline and global plugins).
Plugins are the most efficient way to customize or change the default behavior of a chart.

Author:

Andrea "Stock" Stocchero

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`String`	`getId()` Plugins must define a unique id in order to be configurable. Returns the plugin id.
`void`	`onAfterDatasetDraw(IsChart chart, DatasetPluginItem item)` Called after the 'chart' datasets at the given 'args.index' have been drawn (datasets are drawn in the reverse order).
`void`	`onAfterDatasetsDraw(IsChart chart, double easing)` Called after the 'chart' datasets have been drawn.
`void`	`onAfterDatasetsUpdate(IsChart chart)` Called after the 'chart' datasets have been updated.
`void`	`onAfterDatasetUpdate(IsChart chart, DatasetPluginItem item)` Called after the 'chart' datasets at the given 'args.index' has been updated.
`void`	`onAfterDraw(IsChart chart, double easing)` Called after the 'chart' has been drawn for the specific easing value.
`void`	`onAfterEvent(IsChart chart, ChartNativeEvent event)` Called after the 'event' has been consumed.
`void`	`onAfterInit(IsChart chart)` Called after 'chart' has been initialized and before the first update.
`void`	`onAfterLayout(IsChart chart)` Called after the 'chart' has been layed out.
`void`	`onAfterRender(IsChart chart)` Called after the 'chart' has been fully rendered (and animation completed).
`void`	`onAfterTooltipDraw(IsChart chart, TooltipPluginItem item)` Called after drawing the 'tooltip'.
`void`	`onAfterUpdate(IsChart chart)` Called after 'chart' has been updated and before rendering.
`boolean`	`onBeforeDatasetDraw(IsChart chart, DatasetPluginItem item)` Called before drawing the 'chart' dataset at the given 'args.index' (datasets are drawn in the reverse order).
`boolean`	`onBeforeDatasetsDraw(IsChart chart, double easing)` Called before drawing the 'chart' datasets.
`boolean`	`onBeforeDatasetsUpdate(IsChart chart)` Called before updating the 'chart' datasets.
`boolean`	`onBeforeDatasetUpdate(IsChart chart, DatasetPluginItem item)` Called before updating the 'chart' dataset at the given 'args.index'.
`boolean`	`onBeforeDraw(IsChart chart, double easing)` Called before drawing 'chart' at every animation frame specified by the given easing value.
`boolean`	`onBeforeEvent(IsChart chart, ChartNativeEvent event)` Called before processing the specified 'event'.
`void`	`onBeforeInit(IsChart chart)` Called before initializing 'chart'.
`boolean`	`onBeforeLayout(IsChart chart)` Called before laying out 'chart'.
`boolean`	`onBeforeRender(IsChart chart)` Called before rendering 'chart'.
`boolean`	`onBeforeTooltipDraw(IsChart chart, TooltipPluginItem item)` Called before drawing the 'tooltip'.
`boolean`	`onBeforeUpdate(IsChart chart)` Called before updating 'chart'.
`void`	`onConfigure(IsChart chart)` Called before initializing configuration of 'chart'.
`void`	`onDestroy(IsChart chart)` Called after the chart as been destroyed.
`void`	`onResize(IsChart chart, SizeItem size)` Called after the chart as been resized.

- Method Detail
  - getId
```
String getId()
```
    Plugins must define a unique id in order to be configurable.
    Returns the plugin id. A plugin id
    - can not start with a dot or an underscore
    - can not contain any non-URL-safe characters
    - cannot contain upper-case letters
    - should be something short, but also reasonably descriptive
    Returns:
    
    the plugin id.
  - onConfigure
```
void onConfigure(IsChart chart)
```
    Called before initializing configuration of 'chart'.
    
    Parameters:
    
    chart - the chart instance.
  - onBeforeInit
```
void onBeforeInit(IsChart chart)
```
    Called before initializing 'chart'.
    
    Parameters:
    
    chart - the chart instance.
  - onAfterInit
```
void onAfterInit(IsChart chart)
```
    Called after 'chart' has been initialized and before the first update.
    
    Parameters:
    
    chart - the chart instance.
  - onBeforeUpdate
```
boolean onBeforeUpdate(IsChart chart)
```
    Called before updating 'chart'. If any plugin returns false, the update is cancelled (and thus subsequent render(s)) until another 'update' is triggered.
    
    Parameters:
    
    chart - the chart instance.
    
    Returns:
    
    false to cancel the chart update.
  - onAfterUpdate
```
void onAfterUpdate(IsChart chart)
```
    Called after 'chart' has been updated and before rendering. Note that this hook will not be called if the chart update has been previously cancelled.
    
    Parameters:
    
    chart - the chart instance.
  - onBeforeLayout
```
boolean onBeforeLayout(IsChart chart)
```
    Called before laying out 'chart'. If any plugin returns false, the layout update is cancelled until another 'update' is triggered.
    
    Parameters:
    
    chart - the chart instance.
    
    Returns:
    
    false to cancel the chart layout.
  - onAfterLayout
```
void onAfterLayout(IsChart chart)
```
    Called after the 'chart' has been layed out. Note that this hook will not be called if the layout update has been previously cancelled.
    
    Parameters:
    
    chart - the chart instance.
  - onBeforeDatasetsUpdate
```
boolean onBeforeDatasetsUpdate(IsChart chart)
```
    Called before updating the 'chart' datasets. If any plugin returns false, the datasets update is cancelled until another 'update' is triggered.
    
    Parameters:
    
    chart - the chart instance.
    
    Returns:
    
    false to cancel the datasets update.
  - onAfterDatasetsUpdate
```
void onAfterDatasetsUpdate(IsChart chart)
```
    Called after the 'chart' datasets have been updated. Note that this hook will not be called if the datasets update has been previously cancelled.
    
    Parameters:
    
    chart - the chart instance.
  - onBeforeDatasetUpdate
```
boolean onBeforeDatasetUpdate(IsChart chart,
                              DatasetPluginItem item)
```
    Called before updating the 'chart' dataset at the given 'args.index'. If any plugin returns false, the datasets update is cancelled until another 'update' is triggered.
    
    Parameters:
    
    chart - the chart instance.
    
    item - the dataset item.
    
    Returns:
    
    false to cancel the chart datasets drawing.
  - onAfterDatasetUpdate
```
void onAfterDatasetUpdate(IsChart chart,
                          DatasetPluginItem item)
```
    Called after the 'chart' datasets at the given 'args.index' has been updated. Note that this hook will not be called if the datasets update has been previously cancelled.
    
    Parameters:
    
    chart - the chart instance.
    
    item - the dataset item.
  - onBeforeRender
```
boolean onBeforeRender(IsChart chart)
```
    Called before rendering 'chart'. If any plugin returns false, the rendering is cancelled until another 'render' is triggered.
    
    Parameters:
    
    chart - the chart instance.
    
    Returns:
    
    false to cancel the chart rendering.
  - onAfterRender
```
void onAfterRender(IsChart chart)
```
    Called after the 'chart' has been fully rendered (and animation completed). Note that this hook will not be called if the rendering has been previously cancelled.
    
    Parameters:
    
    chart - the chart instance.
  - onBeforeDraw
```
boolean onBeforeDraw(IsChart chart,
                     double easing)
```
    Called before drawing 'chart' at every animation frame specified by the given easing value. If any plugin returns false, the frame drawing is cancelled until another 'render' is triggered.
    
    Parameters:
    
    chart - the chart instance.
    
    easing - The current animation value, between 0.0 and 1.0.
    
    Returns:
    
    false to cancel the chart drawing.
  - onAfterDraw
```
void onAfterDraw(IsChart chart,
                 double easing)
```
    Called after the 'chart' has been drawn for the specific easing value. Note that this hook will not be called if the drawing has been previously cancelled.
    
    Parameters:
    
    chart - the chart instance.
    
    easing - The current animation value, between 0.0 and 1.0.
  - onBeforeDatasetsDraw
```
boolean onBeforeDatasetsDraw(IsChart chart,
                             double easing)
```
    Called before drawing the 'chart' datasets. If any plugin returns false, the datasets drawing is cancelled until another 'render' is triggered.
    
    Parameters:
    
    chart - the chart instance.
    
    easing - The current animation value, between 0.0 and 1.0.
    
    Returns:
    
    false to cancel the chart datasets drawing.
  - onAfterDatasetsDraw
```
void onAfterDatasetsDraw(IsChart chart,
                         double easing)
```
    Called after the 'chart' datasets have been drawn. Note that this hook will not be called if the datasets drawing has been previously cancelled.
    
    Parameters:
    
    chart - the chart instance.
    
    easing - The current animation value, between 0.0 and 1.0.
  - onBeforeDatasetDraw
```
boolean onBeforeDatasetDraw(IsChart chart,
                            DatasetPluginItem item)
```
    Called before drawing the 'chart' dataset at the given 'args.index' (datasets are drawn in the reverse order). If any plugin returns false, the datasets drawing is cancelled until another 'render' is triggered.
    
    Parameters:
    
    chart - the chart instance.
    
    item - the dataset item.
    
    Returns:
    
    false to cancel the chart datasets drawing.
  - onAfterDatasetDraw
```
void onAfterDatasetDraw(IsChart chart,
                        DatasetPluginItem item)
```
    Called after the 'chart' datasets at the given 'args.index' have been drawn (datasets are drawn in the reverse order). Note that this hook will not be called if the datasets drawing has been previously cancelled.
    
    Parameters:
    
    chart - the chart instance.
    
    item - the dataset item.
  - onBeforeTooltipDraw
```
boolean onBeforeTooltipDraw(IsChart chart,
                            TooltipPluginItem item)
```
    Called before drawing the 'tooltip'. If any plugin returns false, the tooltip drawing is cancelled until another 'render' is triggered.
    
    Parameters:
    
    chart - the chart instance.
    
    item - The tooltip instance.
    
    Returns:
    
    false to cancel the chart tooltip drawing.
  - onAfterTooltipDraw
```
void onAfterTooltipDraw(IsChart chart,
                        TooltipPluginItem item)
```
    Called after drawing the 'tooltip'. Note that this hook will not be called if the tooltip drawing has been previously cancelled.
    
    Parameters:
    
    chart - the chart instance.
    
    item - The tooltip instance.
  - onBeforeEvent
```
boolean onBeforeEvent(IsChart chart,
                      ChartNativeEvent event)
```
    Called before processing the specified 'event'. If any plugin returns false, the event will be discarded.
    
    Parameters:
    
    chart - the chart instance.
    
    event - The event object.
    
    Returns:
    
    false to discard the event.
  - onAfterEvent
```
void onAfterEvent(IsChart chart,
                  ChartNativeEvent event)
```
    Called after the 'event' has been consumed. Note that this hook will not be called if the 'event' has been previously discarded.
    
    Parameters:
    
    chart - the chart instance.
    
    event - The event object.
  - onResize
```
void onResize(IsChart chart,
              SizeItem size)
```
    Called after the chart as been resized.
    
    Parameters:
    
    chart - the chart instance.
    
    size - The new canvas display size (eq. canvas.style width and height).
  - onDestroy
```
void onDestroy(IsChart chart)
```
    Called after the chart as been destroyed.
    
    Parameters:
    
    chart - the chart instance.

Interface Plugin

Method Summary

Method Detail

getId

onConfigure

onBeforeInit

onAfterInit

onBeforeUpdate

onAfterUpdate

onBeforeLayout

onAfterLayout

onBeforeDatasetsUpdate

onAfterDatasetsUpdate

onBeforeDatasetUpdate

onAfterDatasetUpdate

onBeforeRender

onAfterRender

onBeforeDraw

onAfterDraw

onBeforeDatasetsDraw

onAfterDatasetsDraw

onBeforeDatasetDraw

onAfterDatasetDraw

onBeforeTooltipDraw

onAfterTooltipDraw

onBeforeEvent

onAfterEvent

onResize

onDestroy