com.vaadin.flow.data.provider.

java.lang.Object
- com.vaadin.flow.data.provider.AbstractDataView<T>

Type Parameters:

T - data type

All Implemented Interfaces:

DataView<T>, Serializable

Direct Known Subclasses:

AbstractLazyDataView, AbstractListDataView, CheckboxGroupDataView, ComboBoxDataView, GridDataView, ListBoxDataView, RadioButtonGroupDataView, SelectDataView
```
public abstract class AbstractDataView<T>
extends Object
implements DataView<T>
```
Abstract data view implementation which handles parts that apply for any type of data.

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field	Description
`protected Component`	`component`
`protected SerializableSupplier<? extends DataProvider<T,?>>`	`dataProviderSupplier`
`protected static String`	`NULL_IDENTIFIER_ERROR_MESSAGE`
`protected static String`	`NULL_ITEM_ERROR_MESSAGE`

Constructor Summary

Constructors
Constructor	Description
`AbstractDataView(SerializableSupplier<? extends DataProvider<T,?>> dataProviderSupplier, Component component)`	Creates a new instance of `AbstractDataView` subclass and verifies the passed data provider is compatible with this data view implementation.

Method Summary

All Methods
Modifier and Type	Method	Description
`Registration`	`addItemCountChangeListener(ComponentEventListener<ItemCountChangeEvent<?>> listener)`	Add an item count change listener that is fired when the item count changes.
`protected boolean`	`equals(T item, T compareTo)`
`protected IdentifierProvider<T>`	`getIdentifierProvider()`
`Stream<T>`	`getItems()`	Get the full data available to the component.
`protected abstract Class<?>`	`getSupportedDataProviderType()`	Returns supported `DataProvider` type for this `DataView`.
`void`	`refreshAll()`	Notifies the component that all the items should be refreshed.
`void`	`refreshItem(T item)`	Notifies the component that the item has been updated and thus should be refreshed.
`void`	`setIdentifierProvider(IdentifierProvider<T> identifierProvider)`	Sets an identifier provider, which returns an identifier for the given item.
`protected void`	`verifyDataProviderType(Class<?> dataProviderType)`	Verifies an obtained `DataProvider` type is appropriate for current Data View type.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.vaadin.flow.data.provider.DataView
getItem

- Field Detail
  - NULL_ITEM_ERROR_MESSAGE
```
protected static final String NULL_ITEM_ERROR_MESSAGE
```
    See Also:
    
    Constant Field Values
  - NULL_IDENTIFIER_ERROR_MESSAGE
```
protected static final String NULL_IDENTIFIER_ERROR_MESSAGE
```
    See Also:
    
    Constant Field Values
  - dataProviderSupplier
```
protected SerializableSupplier<? extends DataProvider<T,?>> dataProviderSupplier
```
  - component
```
protected Component component
```
- Constructor Detail
  - AbstractDataView
```
public AbstractDataView(SerializableSupplier<? extends DataProvider<T,?>> dataProviderSupplier,
                        Component component)
```
    Creates a new instance of AbstractDataView subclass and verifies the passed data provider is compatible with this data view implementation.
    
    Parameters:
    
    dataProviderSupplier - supplier from which the DataProvider can be gotten
    
    component - the component that the dataView is bound to
- Method Detail
  - addItemCountChangeListener
```
public Registration addItemCountChangeListener(ComponentEventListener<ItemCountChangeEvent<?>> listener)
```
    Description copied from interface: DataView
    
    Add an item count change listener that is fired when the item count changes. This can happen for instance when filtering the items.
    Item count change listener is bound to the component and will be retained even if the data changes by setting of a new items or DataProvider to component.
    NOTE: when the component supports lazy loading (implements HasLazyDataView) and a count callback has not been provided, an estimate of the item count is used and increased until the actual count has been reached. When the estimate is used, the event is fired with the ItemCountChangeEvent.isItemCountEstimated() returning true.
    
    Specified by:
    
    addItemCountChangeListener in interface DataView<T>
    
    Parameters:
    
    listener - item count change listener to register
    
    Returns:
    
    registration for removing the listener
  - getSupportedDataProviderType
```
protected abstract Class<?> getSupportedDataProviderType()
```
    Returns supported DataProvider type for this DataView.
    
    Returns:
    
    supported data provider type
  - verifyDataProviderType
```
protected final void verifyDataProviderType(Class<?> dataProviderType)
```
    Verifies an obtained DataProvider type is appropriate for current Data View type.
    
    Parameters:
    
    dataProviderType - data provider type to be verified
    
    Throws:
    
    IllegalStateException - if data provider type is incompatible with data view type
  - getItems
```
public Stream<T> getItems()
```
    Description copied from interface: DataView
    
    Get the full data available to the component. Data is filtered and sorted the same way as in the component.
    
    Specified by:
    
    getItems in interface DataView<T>
    
    Returns:
    
    filtered and sorted data set
  - refreshItem
```
public void refreshItem(T item)
```
    Description copied from interface: DataView
    
    Notifies the component that the item has been updated and thus should be refreshed.
    For this to work properly, the item must either implement Object.equals(Object) and Object.hashCode() to consider both the old and the new item instances to be equal, or alternatively use the DataView.setIdentifierProvider(IdentifierProvider) to set an appropriate item's identifier.
    This method delegates the update to DataProvider.refreshItem(Object).
    
    Specified by:
    
    refreshItem in interface DataView<T>
    
    Parameters:
    
    item - item containing updated state
    
    See Also:
    
    DataView.setIdentifierProvider(IdentifierProvider)
  - refreshAll
```
public void refreshAll()
```
    Description copied from interface: DataView
    
    Notifies the component that all the items should be refreshed.
    
    Specified by:
    
    refreshAll in interface DataView<T>
  - setIdentifierProvider
```
public void setIdentifierProvider(IdentifierProvider<T> identifierProvider)
```
    Description copied from interface: DataView
    
    Sets an identifier provider, which returns an identifier for the given item. The identifier is used for comparing the equality of items. Usage example: dataView.setIdentifiedProvider(Item::getId);.
    
    Specified by:
    
    setIdentifierProvider in interface DataView<T>
    
    Parameters:
    
    identifierProvider - function that returns the non-null identifier for a given item
  - getIdentifierProvider
```
protected IdentifierProvider<T> getIdentifierProvider()
```
  - equals
```
protected boolean equals(T item,
                         T compareTo)
```

com.vaadin.flow.data.provider.

Class AbstractDataView<T>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface com.vaadin.flow.data.provider.DataView

Field Detail

NULL_ITEM_ERROR_MESSAGE

NULL_IDENTIFIER_ERROR_MESSAGE

dataProviderSupplier

component

Constructor Detail

AbstractDataView

Method Detail

addItemCountChangeListener

getSupportedDataProviderType

verifyDataProviderType

getItems

refreshItem

refreshAll

setIdentifierProvider

getIdentifierProvider

equals